I S S U E S The species dilemma and its potential impact on enforcing wildlife trade laws Rachel L. Jacobs | Barry W. Baker U.S. Fish & Wildlife Service, National Fish & Wildlife Forensics Laboratory, Ashland, Oregon Correspondence Rachel L. Jacobs and Barry W. Baker, U.S. Fish & Wildlife Service, National Fish & Wildlife Forensics Laboratory, 1490 East Main Street, Ashland, Oregon 97520. Emails: [email protected]; [email protected] Abstract The varied answers to the question “What is a species?” provoke more than lively debates in academic circles. They pose practical problems for law enforcement. Commercial wildlife trade threatens many primate species and is regulated through such laws and international agree- ments as the U.S. Endangered Species Act and the Convention on International Trade in Endan- gered Species of Wild Fauna and Flora. Enforcing legislation relies on the ability to identify when violations occur. Species-defining characters may not be preserved in wildlife trade items. For example, pelage patterns and behavioral characters (e.g., vocalizations) are absent from skulls. Accordingly, identifying victims of illegal trade can be difficult, which hinders enforce- ment. Moreover, identifying new species and “splitting” of currently recognized species can result in enforcement lags and regulatory loopholes. Although such negative consequences should not hinder scientific advancement, we suggest that they be considered by primate taxon- omists and provide recommendations to prevent unintended conservation consequences. KEYWORDS CITES, forensics, law enforcement, phylogenetic species concept, primate, taxonomy 1 | INTRODUCTION Based on multiple taxonomic references, the latest book All the World's Primates (AWP) identifies 505 primate species.1 Since its pub- lication in 2016, more species have been described.2–7 The latter group even includes a newly recognized species of great ape, Pongo tapanuliensis.2 New species descriptions often reignite a debate that has long plagued biological sciences: “What is a species?” How much distinctiveness is enough to warrant a new name or to elevate a sub- species to species rank?8–10 Species concepts are often revisited,8–10 and the implications of taxonomic changes on conservation are often discussed.9,11–14 For primates, the increasing number of recognized species is largely because of the wider acceptance of the Phylogenetic Species Concept (PSC).8–10,14,15 This concept defines a species as a diagnos- able group with a pattern of ancestry and descent.16,17 Some authors suggest that the use of the PSC in primate taxonomy is largely driven by conservation motives.8 Regardless of the motives for using the PSC, there are potential positive and negative impacts for conserva- tion. For example, the PSC arguably enhances biodiversity protection by identifying many previously unrecognized species, thus allowing conservation initiatives to be applied t ...

1. I S S U E S
The species dilemma and its potential impact on enforcing
wildlife trade laws
Rachel L. Jacobs | Barry W. Baker
U.S. Fish & Wildlife Service, National Fish &
Wildlife Forensics Laboratory, Ashland,
Oregon
Correspondence
Rachel L. Jacobs and Barry W. Baker,
U.S. Fish & Wildlife Service, National Fish &
Wildlife Forensics Laboratory, 1490 East Main
Street, Ashland, Oregon 97520.
Emails: [email protected];
[email protected]
Abstract
The varied answers to the question “What is a species?”
provoke more than lively debates in
academic circles. They pose practical problems for law
enforcement. Commercial wildlife trade

2. threatens many primate species and is regulated through such
laws and international agree-
ments as the U.S. Endangered Species Act and the Convention
on International Trade in Endan-
gered Species of Wild Fauna and Flora. Enforcing legislation
relies on the ability to identify
when violations occur. Species-defining characters may not be
preserved in wildlife trade items.
For example, pelage patterns and behavioral characters (e.g.,
vocalizations) are absent from
skulls. Accordingly, identifying victims of illegal trade can be
difficult, which hinders enforce-
ment. Moreover, identifying new species and “splitting” of
currently recognized species can
result in enforcement lags and regulatory loopholes. Although
such negative consequences
should not hinder scientific advancement, we suggest that they
be considered by primate taxon-
omists and provide recommendations to prevent unintended
conservation consequences.
KEYWORDS
CITES, forensics, law enforcement, phylogenetic species
concept, primate, taxonomy

3. 1 | INTRODUCTION
Based on multiple taxonomic references, the latest book All the
World's Primates (AWP) identifies 505 primate species.1 Since
its pub-
lication in 2016, more species have been described.2–7 The
latter
group even includes a newly recognized species of great ape,
Pongo
tapanuliensis.2 New species descriptions often reignite a debate
that
has long plagued biological sciences: “What is a species?” How
much
distinctiveness is enough to warrant a new name or to elevate a
sub-
species to species rank?8–10 Species concepts are often
revisited,8–10
and the implications of taxonomic changes on conservation are
often
discussed.9,11–14
For primates, the increasing number of recognized species is
largely because of the wider acceptance of the Phylogenetic
Species
Concept (PSC).8–10,14,15 This concept defines a species as a

4. diagnos-
able group with a pattern of ancestry and descent.16,17 Some
authors
suggest that the use of the PSC in primate taxonomy is largely
driven
by conservation motives.8 Regardless of the motives for using
the
PSC, there are potential positive and negative impacts for
conserva-
tion. For example, the PSC arguably enhances biodiversity
protection
by identifying many previously unrecognized species, thus
allowing
conservation initiatives to be applied to more ecologically and
evolu-
tionarily diverse populations.12,13 Conversely, conservation
options
can become more limited as smaller units (e.g., single
populations)
receive species status by precluding genetic rescue between
newly
distinguished taxa and thus increase inbreeding.11
Unfortunately, one conservation implication is often
overlooked:

5. the effect that changing taxonomy has on enforcing laws aimed
at
protecting wildlife. Importantly, this issue applies to a broad
range of
taxonomic groups, but primates are exemplary for (a) having a
large
number of species newly recognized in recent years (e.g.,
between
1996 and 2016, the number of primate species increased from
~230
to ~500)1,18 and (b) experiencing large population declines due
to
hunting for the wildlife trade.19,20 In discussing this issue, our
goal is
not to argue in favor of one species concept over another, nor is
to
express our opinions about whether certain taxonomic changes
are
warranted. We are forensic scientists working in the United
States on
wildlife crimes; these crimes often involve violations of trade
laws that
include international species. As wildlife forensic scientists,21
we are

6. tasked with identifying victims of the crimes. We aim to give a
victim
Received: 29 March 2018 Revised: 11 July 2018 Accepted: 21
September 2018
DOI: 10.1002/evan.21751
Published 2018. This article is a U.S. Government work and is
in the public domain in the USA.
Evol Anthropol. 2018;27:261–266.
wileyonlinelibrary.com/journal/evan 261
https://orcid.org/0000-0001-6075-7767
https://orcid.org/0000-0001-7037-5682
mailto:[email protected]
mailto:[email protected]
http://wileyonlinelibrary.com/journal/evan
http://crossmark.crossref.org/dialog/?doi=10.1002%2Fevan.217
51&domain=pdf&date_stamp=2018-11-28
a name, a species name when possible. Species-level
identification is
often necessary to determine whether or not a crime has been
com-
mitted, as well as if and how perpetrators will be prosecuted.
Changes
in taxonomy can therefore change the name we are able to give
a vic-

7. tim, which can hinder prosecution, because legislation often
lags
behind scientific advances. Moreover, when new species are
named,
researchers might not yet know the impact (if any) that hunting
pres-
sure for the trade has (or has had) on populations. Accordingly,
data
might be lacking to make appropriate recommendations for
trade
regulations, resulting in inadequate protections. By making
primate
taxonomists aware of these issues, and of the challenges we face
in
wildlife forensic science, we hope that the academic community
will
be able to help prevent potential undesired conservation threats.
2 | WILDLIFE REGULATIONS AND SPECIES
NAMES
Trade in all primates is regulated internationally under the
Convention
on International Trade in Endangered Species of Wild Fauna
and Flora
(CITES), which was established in 1973 to ensure that

8. international
trade in specimens of wild animals and plants does not threaten
their
survival.22,23 Decisions to list species under CITES currently
involve
183 Parties (i.e., 182 countries and one regional economic
integration
organization, the European Union), which are also tasked with
enfor-
cing the regulations.23 These CITES listings do not reflect the
species'
conservation status as determined by the International Union for
Con-
servation of Nature (IUCN) Red List of Threatened Species.
CITES
focuses only on species impacted by trade, whereas IUCN
assesses
species' conservation statuses (e.g., Vulnerable, Endangered,
Critically
Endangered) based on a wide range of threats (http://www.
iucnredlist.org/about/overview). There is collaboration between
these
two entities.24,25 For example, IUCN is involved in reviews of
pro-

9. posed CITES listing amendments for consideration prior to
CITES
decisions.25
Many species are also specifically listed under the
U.S. Endangered Species Act (ESA), which regulates, among
other
activities, national and international trade in threatened and
endan-
gered species involving U.S. jurisdiction;23,26 the list includes
non-
native species (https://ecos.fws. gov/ecp/; note that “threatened”
and
“endangered” status in ESA also differs from that of IUCN, see
ESA definitions at https://www.fws.gov/endangered/laws-
policies/).
Finally, many primates may receive protections under laws
within
their range countries.27–29 Importantly, legislation related to
conserva-
tion and wildlife trade generally defines protections and
regulations
based on species names (or in some cases subspecies names).
Among

10. primates, trade regulations differ across species. For example,
under
CITES, international commercial trade in live primates, as well
as their
parts and derivatives, is either strictly prohibited (appendix I)
or per-
mitted but regulated (appendix II).22,30 The difference between
these
two categories has important implications for prosecuting
violations
of wildlife trade laws. However, the primate remains we often
observe
in the trade, including skulls, body parts (e.g., hands and feet),
bush-
meat, and fragmentary postcranial material, can be difficult to
identify
to species level based on morphology and/or genetics (Figure
1).21
Accordingly, when closely related taxa are split listed, that is,
when
they contain both appendices I and II taxa (e.g., Alouatta,
Ateles, and
Saguinus),22,30 enforcing appendix I violations can be
difficult. ESA vio-

11. lations, where only a limited number of species are listed,26 can
be
equally problematic to enforce.
3 | WILDLIFE FORENSICS AND SPECIES
IDENTIFICATION
If species can be identified as requiring some form of legal
protection,
then how can it be that identifying animals to species is so
difficult?
From a forensics point of view, there are multiple related
reasons. First,
identifications must be ironclad and defensible in a court of
law. The
livelihoods and liberty of the accused are on the line, so
identifications
must be certain. If an evidence item does not exhibit clear
characters
diagnostic to species, then identifications must be made to the
next
lowest taxonomic grouping possible (e.g., genus or family).
Second,
most evidence items are not associated with accurate geographic
infor-

12. mation, and thus, such data cannot be used in identifications.
Third,
primate species are defined based on a variety of criteria. The
“diagno-
sability” aspect of the PSC is not limiting;16,17 different
species may be
considered diagnosable based on genetic, morphological, or
behavioral
characters. If those criteria are not preserved in an evidence
item, as
frequently happens (e.g., pelage coloration is generally not
preserved in
bushmeat material), then identification to species level is not
possible.
Finally, species descriptions are often inadequate for forensic
identifica-
tions. There are a number of reasons why this might be the case.
Spe-
cies names are tied to the type specimen(s),31 and thus the full
range of
variation within a described species may be unknown. For
morphologi-
cal analyses, there may be no (or low quality) illustrations of
species-

13. diagnostic differences. When measurements are critical, raw
data may
be unavailable (species means are of limited value), and often,
it is
unclear what is considered to be a description compared to a
diagnosis,
especially when synapomorphic and autapomorphic traits are
not
clearly defined. For genetic analyses, internal reference
specimens or
published sequences of congeners may be unavailable for
comparison.
4 | TAXONOMIC CHANGES AND
ENFORCING CURRENT REGULATIONS
Many of these challenges to making species identifications are
com-
pounded when there are taxonomic splits, in which multiple
species
are recognized from what was previously recognized as one or
few
species. Again, we do not aim to imply that such changes should
not
be made; science should not have an agenda. Although some
researchers have argued for greater oversight over taxonomic

14. changes,32,33 others have emphasized the dangers such
oversight
could have on scientific progress.31 Our aim is to simply point
out that
such splits have consequences beyond those related to academic
research. One major forensic complication that arises from
taxonomic
splits is related to interpreting previously described variation.
As men-
tioned earlier, forensic wildlife evidence often includes
modified
and/or partial remains. Because species descriptions may be
262 JACOBS AND BAKER
http://www.iucnredlist.org/about/overview
http://www.iucnredlist.org/about/overview
https://ecos.fws.gov/ecp/
https://www.fws.gov/endangered/laws-policies/
inadequate for species-level identification of such items, we
often
incorporate comparative research of particular elements/features
into
our evaluations. It can be difficult to assess whether variation
that

15. was previously observed and described in a species is valid
after a tax-
onomic split. If this is not explicitly addressed in the literature,
or if
raw data and their associated specimens are not available, then
previ-
ously published data under earlier taxonomies are of minimal
use for
forensic identifications. This issue not only impacts our use of
pub-
lished research but also our use of forensic comparative
collections.
By the nature of evidence items, forensic reference collections
are
often atypical compared to museum collections. Similarly,
however,
species names must be reassessed in light of taxonomic changes,
which can result in the same challenges as evaluating evidence
items.
Importantly, beyond forensic identification, changing taxonomy
can have additional consequences related to prosecution and
species
protection. Changing taxonomy can introduce potential

16. loopholes in
law enforcement, because new species names are not necessarily
rec-
ognized by current laws. In such cases, prosecution might be
hindered
and/or it might be necessary to reevaluate the intent of a law,
which
can take time. For example, the scientific community has
recognized
Sumatran and Bornean orangutans as separate species, rather
than two
subspecies, since around 2001.34 It was not until 2018 that the
inter-
pretation of the ESA listing, Pongo pygmaeus, was addressed to
also
include Pongo abelii.35 Fortunately, given the potential new
species
Pongo tapanuliensis,2 the statement further addresses protection
of any
additional species that might be recognized in the future,35 a
welcome
addition to the legislation that we would like to see become
more wide-
spread. CITES appears to update species names more

17. regularly.31 For
example, taxonomic revisions to the genus Pithecia in 201436
are recog-
nized in the online CITES Species+ website,
www.speciesplus.net30.
When taxonomic revisions are accepted, then these species
receive
similar listing status as the taxon from which it was split, which
may or
may not be appropriate. It should also be noted that outside of
the
United States and CITES, range country laws can also be
impacted by
changing taxonomy. For example, a recent article indicated that
Trachy-
pithecus and Semnopithecus (formerly Presbytis) are not
formally
protected under Chinese law, which recognizes the genus
Presbytis
only, introducing a potential line of defense within the court
system.27
We are unaware of whether or not the laws have changed since
the
publication. Given that many countries suffer from very low

18. levels of
prosecution for wildlife crimes,37–39 such obstacles could
make prose-
cution even more difficult. Because there can be an extensive
amount
of time between a potential violation and actual prosecution,
taxonomic
changes could even impact current and ongoing cases.
5 | TAXONOMIC CHANGES AND
POTENTIAL NEED FOR NEW REGULATIONS
Additional impacts related to species protection include the
unfortu-
nate potential for increased pressure on newly recognized
species as
a consequence of their perceived “novelty.”40 Rare primates are
some-
times targeted in wildlife trade (the pet trade in particular) as
status
FIGURE 1 Examples of confiscated primate material. (a) Hand
of Pan sp. (b) Skull of immature Pongo sp. (c) Dried infant
Nycticebus sp. (d) Partial
skin/pelage of Nycticebus sp. Scale bars = 1 cm
JACOBS AND BAKER 263

19. http://www.speciesplus.net
symbols.28,41–43 New species, regardless of their population
numbers,
could be similarly targeted, and this trend has been noted to
occur in
other, nonprimate taxa.40 Finally, as mentioned earlier, trade in
newly
recognized species might not be appropriately regulated. In
cases of
taxonomic splits, the impact of wildlife trade on previously
recognized
widely distributed species might be minimal, but newly
recognized
species with smaller populations could be (or could have been)
more
severely impacted, as has been suggested for the genus
Aotus.28,29
Aotus (night monkeys) has undergone several taxonomic
revisions,
from which one species is now often recognized as 11.29 Legal
trade
in Aotus species (CITES appendix II; nine species recognized)
is rela-

20. tively high among primates and might impart unsustainable
pressure
on rarer species.29 Importantly, it is difficult to actually assess
the
impact of trade on Aotus species, in part, because not all
species are
currently recognized by CITES and not all traded animals (legal
and
illegal) are identified to species.29 Moreover, identification to
Aotus
species can be difficult for law enforcement due to
morphological sim-
ilarities.29 In such cases, if a change in regulation status is
decided for
some but not all species, it could be difficult to enforce.
Accordingly,
changes to trade regulations may need to occur at the genus
level
(or higher), as was successfully done for the genus Nycticebus.
In
recognition of the large impact that the wildlife trade has on
slow
lorises, as well as the ongoing taxonomic changes within this
group,

21. the genus Nycticebus was elevated to appendix I under CITES
in 2007
(i.e., all trade prohibited).44,45
When legislative changes appear warranted, members of the
aca-
demic community can be advocates for change. For example,
they can
regularly check and comment on Federal Register documents
(https://
www.federalregister.gov/). They can provide concerns about
CITES
listing statuses to the governments of primate range countries in
which they work or nongovernmental agencies that are
observers at
CITES conferences; changes to regulations require proposals
from
Parties.23 It is important to note, however, that
recommendations for
legislative changes should be carefully considered. For
example, spe-
cies that are deemed to be threatened with extinction by the
IUCN
(e.g., Endangered, Critically Endangered) might not be severely
threat-

22. ened by wildlife trade. Decisions to elevate species under the
CITES
trade agreement could have negative conservation consequences
by
stimulating/increasing trade.46
Clearly, the relationships among changing taxonomy,
legislation,
and law enforcement are complex. In recognition, some have
argued
for refinements to legislation that accommodate changing
TABLE 1 Suggestions for researchers to aid forensic
identification of species in the wildlife trade
General guidelines
Be aware that taxonomic changes can have law enforcement
implications.
Be aware of range country laws and taxonomy used in those
legal systems.
Ensure range countries are aware of any previously unknown
occurrences of species within their borders, so that protective
legislative action can be
considered.27 However, be aware that public geographic
information can pose significant threat to species.40
Consider that changes to legislation and trade agreements might
be better made prior to publishing taxonomic revisions/species

23. descriptions.53
Be aware that within many countries, there are limited resources
for wildlife law enforcement. Accordingly, many forensic
analyses (e.g., genetics)
might not be possible.29 Morphological identification when
feasible is faster and cheaper. That said, requirements for
forensic identifications might
differ among countries, with certain techniques being favored or
required over others. Researchers should communicate with
local governments
and international trade authorities to discuss the impacts of
species identifications and taxonomic changes.29
Be aware that morphological and genetic reference samples are
needed for forensic species identification. Lack of access to
such material is often a
limiting factor in successful law enforcement efforts.
Recommendations
Species descriptions
Be explicit and detailed in describing, illustrating, and
publishing morphological diagnoses.
Clearly distinguish between morphological descriptions and
morphological diagnoses. Synapomorphies and autapomorphies
should be clearly described
and illustrated.
Note species that might be confused with a newly
described/elevated species so that the need for broader
protection/regulation (e.g., genus level)
might be better assessed.

24. Be explicit on synonymy to help legal systems interpret your
publications.
Make vouchered photographic databases publicly available.a
Make diagnostic vouchered mitochondrial and nuclear
sequences publicly available (e.g., through online databases,
such as GenBank).a
Create identification guides for species based on taxonomic
revisions in the languages of species range countries, as well as
those countries
potentially involved in trade import and transit.
General research
Publish research on basic morphological description and genetic
characterization. These might not seem to be the most ground-
breaking publications,
but they are important. In fact, basic descriptive morphological
or genetic differences are often more useful in a forensic
context than are
functional/evolutionary explanations of the characters
observed.b
If possible, fully document variability for species, sexes, and
age ranges. Morphological outliers are often submitted as
forensic evidence because their
appearance is so unusual.
Make raw morphometric data and their associated specimen
numbers publicly available.a
a Many researchers and publishers are already providing public
access to published data. Publishers can help ensure data are
publicly available and accessi-

25. ble by requiring deposition prior to official publication and
release of new species names.
b We acknowledge that publishers may be a barrier if they deem
such studies as low impact or narrow in scope. Journals
specifically aimed at publishing
data (e.g., BMC Research Notes) might help overcome this
obstacle.
264 JACOBS AND BAKER
https://www.federalregister.gov
https://www.federalregister.gov
taxonomy.31 It is also helpful if legislative decisions consider
the
unique impacts taxonomic changes can have on wildlife forensic
iden-
tification (e.g., whether species-level identification is feasible).
Unfor-
tunately, legislative change can be slow. In the meantime, there
are
steps that researchers can take to help reduce the challenges
related
to forensic identification (Table 1).
In closing, we note again that this issue can be more broadly
applied to other biological taxa. As wildlife forensic scientists,
we are

26. tasked with identifying a much broader group of animals (RLJ—
all
mammals; BWB—all herpetofauna), and changing taxonomy, in
partic-
ular taxonomic splitting, is widespread.47–52 Through
increased aware-
ness and continued discussion, we hope to bridge the gap
between
alpha taxonomy and its applied use in a forensic context. Many
pri-
mate species face staggering challenges to their survival.19,20
It is
therefore imperative that academic and applied researchers work
together when possible to help reduce some of these threats.
The findings and conclusions in this article are those of the
author(s) and do not necessarily represent the views of the U.S.
Fish
and Wildlife Service.
ACKNOWLEDGMENTS
The authors thank Pepper Trail and Thomas Leuteritz for
helpful com-
ments on earlier versions of this manuscript.

27. CONFLCIT OF INTEREST
The authors declare that there are no conflicts of interest.
ORCID
Rachel L. Jacobs https://orcid.org/0000-0001-6075-7767
Barry W. Baker https://orcid.org/0000-0001-7037-5682
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AUTHOR BIOGRAPHIES
RACHEL JACOBS is a forensic mammalogist with a
background in biologi-
cal anthropology. Her past and ongoing research has focused on
the
behavior, ecology, population genetics, and morphology of
living
primates.
BARRY BAKER is a wildlife forensic scientist with a
background in
zooarchaeology and biological anthropology. His past and
ongoing
research has focused on skeletal morphology and the forensic
identifi-
cation of reptiles and mammals in the wildlife trade.
How to cite this article: Jacobs RL, Baker BW. The species
dilemma and its potential impact on enforcing wildlife trade

37. laws. Evol Anthropol. 2018;27:261–266. https://doi.org/10.
1002/evan.21751
266 JACOBS AND BAKER
https://www.cites.org/sites/default/files/eng/cop/14/prop/E14-
P01.pdf
https://www.cites.org/sites/default/files/eng/cop/14/prop/E14-
P01.pdf
https://doi.org/10.1002/evan.21751
https://doi.org/10.1002/evan.21751 The species dilemma and its
potential impact on enforcing wildlife trade laws1
INTRODUCTION2 WILDLIFE REGULATIONS AND
SPECIES NAMES3 WILDLIFE FORENSICS AND SPECIES
IDENTIFICATION4 TAXONOMIC CHANGES AND
ENFORCING CURRENT REGULATIONS5 TAXONOMIC
CHANGES AND POTENTIAL NEED FOR NEW
REGULATIONS5 ACKNOWLEDGMENTS CONFLCIT OF
INTEREST REFERENCES
INSTRUCTIONS ON BRIEFING CASES
In analyzing a legal case, you have to present a brief. The
instructions below will
guide you in doing your case (legal) brief.
FIRAC: FACTS-ISSUE-RULE OF LAW-ANALYSIS-
CONCLUSION:
HOW TO BRIEF A CASE
1. (F): FACTS: State the facts of the case (a brief summary of
what the case is about, i.e., what happened?). This is a
synopsis of the essential facts of the case. These facts lead up to
the Issue.
2. (I): ISSUE/ISSUES: State the Issue/Issues in the case (What

38. are the legal issues in the case? Sometimes there may be only
one legal issue). Issues are stateme nts of the general legal
questions answered by or illustrated in the case. Very
Important: The Issue is best put in the form of a question,
capable of a “yes” or “no” answer.
3. (R): RULE OF LAW: This is a statement of the general
principle of law which the case illustrates. You must state the
Rule of Law that applies to the particular case (What law
applies to this case? What does the law say about cases of this
nature?).
4. (A) ANALYSIS: HOLDING AND DECISION: Analysis of
the legal argument/arguments in the case (analyze the
arguments/ decisions/opinions of the justices). This section of
the case should succinctly explain the rationale of the court in
arriving at its decision. In other words, indicate the outcome of
the case.
5. (C) Conclusion (do you agree with the Court’s
arguments/decision/opinion in this case?). If yes, why? And if
not, why not?
Your Legal Brief should be detailed, addressing all the five
steps above. If you use other people ideas to support your
opinion, please make sure that you document or cite the sources
of those ideas to avoid plagiarism. Remember to give credit for
an idea or opinion that is NOT originally yours. In citing your
sources, please use the APA Style (See your Course Syllabus
about the APA Style of Writing).
SAMPLE LEGAL BRIEF: BURGER KING CORP v.
RUDZEWICZ (1985)
NOTE: (P) is for Plaintiff (one who sues) and (D) is for
Defendant (one who is sued and must defend himself/herself).
Jurisdiction means authority to hear a case and Home Forum
means the venue or place for the trial.
Here is a sample legal brief of the famous Burger King case:

39. Follow the FIRAC Steps below.
1. FACTS: Facts of the case (Summary): Rudzewicz (D)
contracted for a Burger King franchise in Michigan with the
Burger King Corp. (P), a Florida corporation. A franchise was
granted. The terms of the contract called for substantial
supervision of the franchise’s operations by Burger King (P),
and also for the laws of Florida to apply in the case. Despite the
fact that Rudzewicz (D) was a sophisticated businessman, the
business failed, and Burger King brought suit for unpaid rent.
The Florida district court granted damages and injunctive relief
to Burger King (P), but the Eleventh Circuit reversed the
decision, holding that Rudzewicz (D) was not subject to Florida
jurisdiction. In other words, Burger King won its case in the
Florida District Trial Court but then appealed to the federal
Circuit Court (Eleventh Circuit Court) where the District Court
decision was reversed. Burger King (P) appealed to the Supr eme
Court of the U.S., arguing for a reversal of award of damages
and injunctive relief for breach of contract by Rudzewicz.
2. ISSUE: May direct and continuous contacts by a franchisee
with the franchisor lead to the franchisee being subject to the
jurisdiction of the franchisor’s home forum?
3. RULE OF LAW: Direct and continuous contacts by a
franchisee with the franchisor may lead to the franchisee being
subject to the jurisdiction of the franchisor’s home town.
4. HOLDING/DECISION OF THE SUPREME COURT: YES.
Justice Brennan (Brennan, J.), writing for the Majority, held
that direct and continuous contacts by the franchisee with the
franchisor may lead to the franchisee being subject to the
jurisdiction of the franchisor’s home forum.
· Analysis: In this case, the main test for personal jurisdiction is
whether a defendant’s actions were such that he should have
been notified of the possibility of becoming subject to the
subject’s forum’s jurisdiction. In his case, Rudzewicz (D)
contracted with the Florida franchisor and entered into a
contract providing for a continuous relationship with that

40. franchisor and constant monitoring by the franchisor. Further,
the contract stated that it was to be construed as a Florida
contract. Thus, considering Rudzewicz’s (D) contacts with
Florida, an adequate basis for jurisdiction existed. Thus, the
Supreme Court of the U.S. REVERSED the decision of the
Eleventh Circuit and ruled in favor of Burger King.
Dissent: (Stevens, J.). Justice Stevens dissented, arguing that
the Burger King was typical and large operation connected to
the franchisor’s home office only in name. Since the business
was purely local, only local jurisdiction should apply.
5. CONCLUSION: Burger King (P) brought an action against
Rudzewicz, a defaulting franchisee, in Burger King’s (P) home
forum, that is, in Florida and not in Rudzewicz home forum.
The rationale for the Supreme Court’s opinion in deciding for
Burger King was the clause making the contract a Florida one.
Most contracts involving parties in different states have such
clauses. Thus, the Court determined that there was direct and
continuous contacts by the franchisee, Rudzewicz (D) and the
franchisor, Burger King (P). Rudzewicz (D) was therefore
subject to the jurisdiction of Burger King’s (P) home forum of
Florida.
Journal of Anthropological Archaeology 35 (2014) 32–50
Contents lists available at ScienceDirect
Journal of Anthropological Archaeology
j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c
a t e / j a a
The place of the Neanderthals in hominin phylogeny
http://dx.doi.org/10.1016/j.jaa.2014.04.004
0278-4165/� 2014 Elsevier Inc. All rights reserved.
⇑ Corresponding author.

41. E-mail address: [email protected] (M. Grove).
Suzanna White, John A.J. Gowlett, Matt Grove ⇑
School of Archaeology, Classics and Egyptology, University of
Liverpool, William Hartley Building, Brownlow Street,
Liverpool L69 3GS, UK
a r t i c l e i n f o a b s t r a c t
Article history:
Received 8 May 2013
Revision received 21 March 2014
Available online 13 May 2014
Keywords:
Neanderthals
Taxonomy
Species status
Debate over the taxonomic status of the Neanderthals has been
incessant since the initial discovery of the
type specimens, with some arguing they should be included
within our species (i.e. Homo sapiens nean-
derthalensis) and others believing them to be different enough
to constitute their own species (Homo
neanderthalensis). This synthesis addresses the process of
speciation as well as incorporating information
on the differences between species and subspecies, and the
criteria used for discriminating between the
two. It also analyses the evidence for Neanderthal–AMH
hybrids, and their relevance to the species
debate, before discussing morphological and genetic evidence
relevant to the Neanderthal taxonomic
debate. The main conclusion is that Neanderthals fulfil all
major requirements for species status. The
extent of interbreeding between the two populations is still
highly debated, and is irrelevant to the issue
at hand, as the Biological Species Concept allows for an
expected amount of interbreeding between

42. species.
� 2014 Elsevier Inc. All rights reserved.
Introduction
Neanderthals were given the Linnaean name of Homo neander-
thalensis after King’s (1864) description of the original type-
speci-
mens, which he felt were so different from modern Homo
sapiens
that they may even represent a new genus. King’s (1864)view
con-
trasts with Huxley’s (1863) classification of Neanderthals as a
sub-
species of human (Homo sapiens neanderthalensis), owing to
the
latter’s belief that they could be included in Linnaeus’ (1802)
H.
sapiens despite their primitive nature (Tattersall, 2007). The
debate
continues into modern research, with some believing
Neanderthals
are sufficiently differentiated to constitute a separate species
(e.g.
Tattersall, 1986; Holliday, 2006), and others disagreeing (e.g.
Dobzhansky, 1944; Currat and Excoffier, 2004). A recent
preference
for the species classification has arisen (de Vos, 2009),
although a
group of recent papers using studies of the Neanderthal genome
(Green et al., 2010; Mendez et al., 2012; Wall et al., 2013)
strongly
indicating interbreeding between Anatomically Modern Humans
(henceforth AMH) and Neanderthals, has re-awakened the
debate.

43. There is a very real need to return to the rules and methods of
traditional taxonomy to further our understanding of what
species
are and how to identify them. The use of such classification sys -
tems is essential for valid conclusions, as they are based on
univer-
sal patterns found in all species, and thus have to be applicable,
despite inherent anthropocentrism and a subsequent belief that
AMH are innately different to other organisms. This article
aims
to draw from taxonomic biology, identifying the methods of
distin-
guishing species and subspecies before assessing the relevant
mor-
phological and genetic evidence, as well as the supposed direct
evidence of interbreeding between these two populations in the
form of hybrids.
The species ‘problem’
The ‘species problem’ is largely a result of the philosophy and
history of the field of taxonomy (Ghiselin, 1974). The main
issues
can be assigned to three categories: definition and concepts of
what constitutes a ‘species’; the speciation process; and debates
concerning criteria for species identification (Simpson, 1961; de
Queiroz, 2005). While species are fundamental to the study of
evo-
lution (Tattersall, 1986), they are considered by some to be
arbi-
trary (Dobzhansky, 1935; Foley, 1991), and to lack a single
reality over a geographic and temporal range (Simpson, 1951;
Foley, 1991; Mallet, 2007).
Definition of ‘species’

44. The first problem lies in an inconsistency in the use and
meaning
of the term ‘species’. Different definitions include: a rank in a
Lin-
naean hierarchy using individual attributes to encompass all
organ-
isms at the species level (Quicke, 1993; Mayr, 1996), the end
product of speciation (Nixon and Wheeler, 1990; Shaw, 1998),
or
the concept of what it is to be a species and what this category
http://crossmark.crossref.org/dialog/?doi=10.1016/j.jaa.2014.04.
004&domain=pdf
http://dx.doi.org/10.1016/j.jaa.2014.04.004
mailto:[email protected]
http://dx.doi.org/10.1016/j.jaa.2014.04.004
http://www.sciencedirect.com/science/journal/02784165
http://www.elsevier.com/locate/jaa
S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50 33
represents (Kimbel and Rak, 1993; de Queiroz, 1998). Issues
arise
over the inherent tautology of definitions, with species
frequently
being defined as ‘whatever a competent taxonomist says is a
spe-
cies’ (Quicke, 1993).
The nature and definition of species is intimately linked to the
process of speciation, as species are dynamic parts of this
overall
process (Harrison, 1998) and can therefore only be an abstract
cat-
egory (Dobzhansky, 1935). Speciation in mammals is a gradual

45. process not an instantaneous event (Simpson, 1951; Mayr and
Ashlock, 1991; de Queiroz, 1998), which means we should
expect
to find organisms representing the entire panoply of stages, not
just the end product (Mayr, 1964, 1996; Mayr and Ashlock,
1991). Five such stages have been proposed for gradualistic
speci-
ation: local populations, subspecies, semi-species, sibling
species,
and morphologically different species (Masters, 1993), yet
distin-
guishing between these stages is more difficult.
Species concepts
Most debate is over the true ‘concept’ of species (Hey, 2006),
as
frameworks for study and identification of species are
dependent
on the researcher’s species concept (Quintyn, 2009). All
concepts
are arbitrary to some extent (Reydon, 2004), with different con-
cepts producing different numbers of taxa (Foley, 1991;
Balakrishnan, 2005). Some have argued that the ‘Species
Concept’
problem is itself a fallacy, as all researchers seem to agree on
one
concept in the linguistic sense at least, with species being the
tip
of an evolutionary lineage (Hey, 2006). Fig. 1 gives an
indication
of the complex development of this area of the philosophy of
tax-
onomy, with the number of current species concepts being at
least
Fig. 1. ‘Phylogeny’ of species con
23 (Quintyn, 2009). The eight main concepts with relevance to

46. this
matter are summarised in Appendix A.
The definitions of species provided by the Phylogenetic and
Evolutionary Species Concepts are readily applicable to the
Nean-
derthal species debate, and would support species status in the
sense that there is a consistent use of morphology to identify
Nean-
derthal specimens and that this population eventually arrived at
extinction. The Recognition Concept (Paterson, 1981) identifies
species through species-specific mating recognition systems
(SMRS), which have been tentatively inferred in fossil
hominins.
For instance, as Neanderthals and AMH are clearly different in
appearance to palaeoanthropologists, they must at least
represent
different subspecies (Tattersall, 1992). However this concept
has
been said to overestimate (Tattersall, 1992) or underestimate
(Kimbel, 1991) the number of species, as hominid skeletons do
not have obvious morphological features that can be linked to
SMRS (Kimbel, 1991), and its tautological nature has been
revealed
upon application to extant primates (Jolly, 1993).
Most debate over species classification uses the Biological Spe -
cies Concept proposed by Mayr (1964) and Dobzhans ky (1935),
which defines species as reproductively isolated populations.
According to the criterion of complete reproductive isolation,
Neanderthals and AMH would have to be classified as the same
species if interbreeding did occur. Yet this strict criteri on was
objected to by both Darwin and Wallace. Wallace took his
objec-
tion further by highlighting the circular reasoning of defining
and

47. delimiting a taxon by the same criteria (Mallet, 1995). The
require-
ment of complete reproductive isolation is a common
misconcep-
tion: Mayr himself acknowledged that occasional hybridisation
occurs between sympatric species (Mayr, 1964, 1996), as
isolation
mechanisms do not prevent all interbreeding, with their main
role
cepts (Quintyn, 2009: 310).
Table 1
Four classes of subspecies definitions (Long and Kittles, 2003,
p. 468).
Class Definition
Essentialist – Share a combination of derived traits
– Features more or less obscured by individual variations
Taxonomic – Aggregate populations sharing phenotypic
similarities
– Inhabit geographic subdivision of range of the species
– Differ taxonomically from other intraspecific populations
Population – Genetically differentiated and distinct Mendelian
populations
– Consist of genetically differentiated individuals
Lineage – A distinct evolutionary lineage within a species
– Genetically differentiated due to barriers to genetic exchange
over time
– Historical continuity and genetic differentiation

48. 34 S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50
being protection of a harmonious gene pool (Mayr, 1996). As
shall
be shown, interbreeding freely occurs between different taxo-
nomic levels without compromising species status. Most accept
the main principles of this concept and use it to provide
practical
guidelines (Tattersall, 1992), overcoming the main issues by
mod-
ifying and supplementing this concept with other, more
appropri-
ate concepts (Simpson, 1951).
Species criteria and methods of delimitation
Criteria used to delineate species boundaries inevitably arise
from the Species Concept that is being applied (Quintyn, 2009).
There are fundamental problems with creation of appropriate
cri-
teria, mainly due to the occurrence of mosaic evolution, with
dif-
ferent characteristics evolving at different rates (Mayr, 1996).
Taxonomy largely depends on morphological characteristics
(Simpson, 1961; Smith, 1994; Mayr, 1996), despite an indirect
rela-
tionship between morphology and genetics (through
reproductive
isolation) (Simpson, 1961; Mayr and Ashlock, 1991). This,
accom-
panied by inapplicability of many species ‘criteria’ to fossil
samples
(Tattersall, 1986) and small sample bases (Simpson, 1961),
compli-
cates the practice of species delineation, especially when
consider-

49. ing the Biological Species Concept.
Despite these inherent problems, certain criteria are regularly
used, including:
– Reproductive isolation (Simpson, 1951; Harrison, 1998)
which
can involve:
� Genetic exclusivity (Harrison, 1998).
� Genotypic clusters (Harrison, 1998).
– Morphological divergence (Simpson, 1951) potentially
leading
to:
� Autapomorphies (Nixon and Wheeler, 1990).
� Fixation of characters (Kimbel and Rak, 1993).
– Ecological distinctiveness (Simpson, 1951; Harrison, 1998).
– Separate evolutionary identities and tendencies (Simpson,
1951; Harrison, 1998).
All species criteria require some level of qualitative, subjective
judgement (Sites and Marshall, 2004). For instance
interbreeding,
where Mayr himself (Mayr, 1964), along with many others
(Simpson, 1951; Harrison, 1998) acknowledges that
interbreeding
may occur between populations that nevertheless retain their
genetic and morphological identities. This criterion cannot be
used
in isolation (Mayr, 1964), and should be considered as a
sufficient
indication of species status, rather than a necessary criterion
(Balakrishnan, 2005). Genetic criteria have their associated
issues,

50. with their validity under constant debate (Masters, 1993).
Morpho-
logical criteria require an arbitrary level for a ‘sufficient’ level
of
divergence (Sites and Marshall, 2004), as does character
fixation,
where ‘true’ (100%) fixation is statistically impossible to prove
(Wiens and Servedio, 2000).
Traditional taxonomy
Traditional taxonomy could be said to use primarily the Typo-
logical Species Concept (Mayr, 1996; Boggs, 2001), based upon
Lin-
naeus’ own idea of species as static groups forming the lowest
category in his hierarchy (Mayr and Ashlock, 1991; Tattersall,
1992), marked by sharp discontinuity (Mayr and Ashlock, 1991)
and representing divine origin (Mayr, 1964). This idea has been
lar-
gely rejected by many researchers, owing to the problems that
arise in polytypic species (Mayr and Ashlock, 1991). Instead,
the
modern typological concept defines species as a ‘class of
individu-
als sharing defining attributes’ (Boggs, 2001). It has the
advantage
that it can be applied to most cases, but involves a subjective
deci-
sion over which traits to use (Boggs, 2001).
As can be seen, the primary criteria (for fossils at least) are
mor-
phological, with the assumption being that morphology approxi-
mates genetic differences (Simpson, 1943). This
‘morphospecies’
concept is the main method used in palaeontological taxonomy

51. (Holliday, 2003) due to its practicality. However the
evolutionary
meaning of such groups is speculative at best (Holliday, 2003;
Ahern, 2006). In addition, the indirect relationship between
mor-
phology and speciation (Foley, 1991; Mayr, 1996; Tattersall and
Schwartz, 2006) invalidates the original assumption, although
counterarguments allege that morphological differences should
suggest absence of reproductive isolation (Simpson, 1951;
Wiens
and Servedio, 2000). Morphological criteria are, again,
subjective
and could ignore the evolutionary significance of species
(Simpson, 1951). Nevertheless, such methods have some
efficacy,
as behaviour and morphology could be considered more relevant
to the production of species than genetic differences (Mallet,
2007), and morphology at least provides a clear method for
species
demarcation (Mayr, 1996).
Subspecies
Subspecies can be defined as a group of organisms in which
interbreeding with other subspecies occurs regularly (Simpson,
1943), with each variant normally marked by significant
morpho-
logical differences (Keita et al., 2004). Genetically, subspecies
exist
as open systems (Dobzhansky, 1935) which may intergrade
almost
unnoticeably (Mayr, 1964) or be separated by a migration
barrier
(Livingstone and Dobzhansky, 1962). Four different definitions
exist, summarised in Table 1. There is a trend towards the
rejection
of the term in scientific circles due to its ability to obscure the

52. more important relationships between members of populations
(Gould, 1991), and application requires a minimum threshold of
difference, as each population will have developed some genetic
or morphological characteristic by which they could be distin-
guished from other groups (Templeton, 1999).
The subspecies taxon is relatively more arbitrary than that of
species (Tetushkin, 2001), although Livingstone and
Dobzhansky
(1962) have argued that the naming and identification are
subjec-
tive, whereas their existence is indisputable. Identification
requires
a large series of comparisons over the geographic range of the
spe-
cies (Mayr, 1964), posing immediate problems for identification
in
the archaeological record. Methods can be made more objective,
for example through the 75% rule where over 75% of a
subspecies
should be distinguishable by diagnostic characters (Mayr,
1964),
or more subjective, where contemporaneous subgroups in a
larger
morphological group may be distinguishable (Simpson, 1943).
There are no agreed criteria for distinguishing subspecies (Long
and Kittles, 2003), with the main criterion being whether the
Table 2
Five types of allopatry (Mayr et al., 1953).
S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50 35
intraspecific variation is greater than interspecific variation

53. among
groups (Long and Kittles, 2003).
Contact Interbreeding Zone of
contact
Taxonomic
classification
1 In contact – Intergradation/
interbreeding in
zone of contact
Fairly wide – Same species
– Subspecies status
dependent on degree
of difference
2 In contact – Interbreed
completely in zone
of contact
Narrow – Same species
– Subspecies
3 In contact – Do not
interbreed freely
– Separate, full
species
– Occasional
hybrids
4 In contact – No interbreeding – Full species
– Reproductive
isolation

54. 5 Separated – No interbreeding Distributional
gap
– Unsure
– Use morphology to
infer taxonomic
status
– Preferable to treat
as subspecies
Hybridisation
The definition of hybridisation that will be used is ‘‘interbreed-
ing between individuals from genetically differentiated lineages
over a wide range of taxonomic levels’’ (Jolly, 2001;
Ackermann,
2010). This process has been largely ignored or misunderstood,
possibly due to the nature of cladistics itself, which is
inherently
ineffective at identifying hybridisation (Holliday, 2003).
However,
Jolly (2001) has demonstrated how the acceptance of
hybridisation
can facilitate greater parsimony in cladistic phylogeny.
Hybridisa-
tion is widespread in many groups of animals (Ackermann,
2010).
Among primates, hybridisation occurs in Cercopithecidae
(Cortés-
Ortiz et al., 2007), Papionins (Jolly, 2001; Arnold and Meyer,
2006; Burrell et al., 2009), Gibbons (Arnold and Meyer, 2006),
Orang-utans (Arnold and Meyer, 2006), Gorillas (Ackermann
and
Bishop, 2009), and Chimpanzees (Arnold and Meyer, 2006).
Con-
sidering this widespread occurrence in the Primate order and the

55. close genetic relationship between members of the Hominini
(Holliday, 2003), the assumption that hybridisation did not
occur
during hominin evolution is questionable and is likely to lead to
inaccuracies in reconstruction.
Speciation is generally considered to be gradual process that
can take between 2 and 4 Ma (Ackermann, 2010), with hybrid
invi-
ability in mammals occurring at the end of this process
(Fitzpatrick, 2004). Post-zygotic isolating mechanisms in
mammals
evolve over much longer timescales than behavioural or
morpho-
logical differentiation, meaning that if taxa meet after
experiencing
significant periods of isolation, reproduction could occur if not
pre-
vented by pre-zygotic isolating mechanisms (Grant and Grant,
1998; Holliday, 2006). A strongly relevant example is the high
probability of gene exchange between human and chimpanzee
ancestors up to 4 Ma after their initial divergence (Bower, 2006;
Patterson et al., 2006; but see Wakeley, 2008; Webster, 2009),
and another is the documented hybridisation between Alouatta
palliate and Alouatta pigra, species that diverged over 6 Ma
(Arnold and Meyer, 2006). Holliday (2006) found that 172 out
of
328 documented occurrences of hybridisations between taxo-
nomic species produce fertile, viable offspring. Considering the
evi-
dence, later Homo sp. could be said to be members of a
syngameon,
a term introduced by Lotsy (1925) referring to a larger group of
species capable of successful hybridisation (Holliday, 2006).
The BSC incorporates a certain level of hybridisation, demon-

56. strated by Mayr’s discussion of the five different kinds of
allopatry
(shown in Table 2) in relation to interbreeding and taxonomic
clas-
sification, which shows that separate species can be capable of
interbreeding in certain circumsta nces. The Neanderthal–AMH
interaction could be characterised as either condition 2, 3 or 4.
In
general, the conclusion that hybridisation between AMHs and
Neanderthals would indicate the conspecificity of these groups
is
false (Ackermann, 2010) and a result of misdirected application
of the species concept (Hey et al., 2003; Arnold and Meyer,
2006). The ‘issue’ of hybridisation does not exist, if one defines
spe-
cies as lineages remaining cohesive despite occasional genetic
exchange (Holliday, 2003).
Very low levels of interbreeding are required for favourable
genes to spread between taxa (Barton, 2006) even if selection
against hybrids occurs (Holliday, 2006) with the only
requirement
being that at least some of the hybrids are partially viable and
fer-
tile (Jolly, 2001). In fact, genes introduced through
hybridisation
could have a higher probability of spreading through a
population’s
genome due to the nature of hybridisation. These genes, unlike
those arising through mutation, have been subject to selection
within their original genome, and are therefore unlikely to be
lethal. If they are disadvantageous they may be removed by the
process of natural selection, meaning that they have a higher
prob-
ability of being advantageous. This in turn means that those
genes

57. which are mutually advantageous to both hybridising
populations
could rapidly reach fixation (Jolly, 2001). In relation to
Neander-
thal–AMH hybridisation, Jolly (2001) argued the issue of
whether
genetic evidence would survive in the face of the effects of later
colonisation and genetic drift (Jolly, 2001): the recent studies of
the Neanderthal genome indicate that it may do so (Green et al.,
2010; Mendez et al., 2012; Wall et al., 2013).
Recognising hybridisation in the fossil record
We have little knowledge of what a hybrid fossil would look
like
(Ackermann, 2010), with Jolly (2001: 190) stressing the
‘‘vanish-
ingly small’’ chances of recognising a Neanderthal–AMH
hybrid.
This position is the result of our lack of knowledge about the
effect
of genetic introgression on the phenotype and the validity of the
assumption that such genes will be directly linked to
morphology
(Jolly, 2001; Ackermann, 2010). The uncertainty is exacerbated
by
the fact that the fossil evidence is likely to underestimate
physical
differences between specimens (‘Tattersall’s Law’) (Tattersall,
1993), and Jolly’s (2001) study of Papionin hybridisation
empha-
sises the point. Beyond question we are restricted by the
absence
of soft-tissue characteristics as well as the small samples
available
from an incomplete fossil record (Ackermann, 2010).

58. Jolly has emphasised the consequent need to rely on analogies,
for instance his direct analogy of the relationship between
Hama-
dryas (Papio hamadryas) and Anubis (Papio anubis) baboons,
which
produce natural hybrids after a divergence time of 600 Ka
(Jolly,
2001). Such comparisons demonstrate that the assumed pattern
of intermediate morphology is only one of many possible out-
comes, including: cryptic hybrids (those indistinguishable from
one of the parental taxa), transgressive hybrids (those showing
variation outside of the range of the parental taxa) and hybrids
with phenotypes closer to one parental taxon rather than the
other
(Ackermann, 2010). Possible indicators could include
intermediate
characteristics, rare anomalies, or complicated patterns of
synapo-
morphies and high levels of individual variability (Harvati et
al.,
2007; Ackermann and Bishop, 2009; Ackermann, 2010),
although
these are features observed in hybrids of different genera and
may be less applicable to hominins.
36 S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50
Evidence of Neanderthal–AMH hybrids
The possibility of Neanderthal–AMH hybrids has long been
recognised, for instance with Dobzhansky’s (1944) proposition
that
the Mount Carmel specimens could indicate subspecific
hybridisa-

59. tion (Grant and Grant, 1998). Other examples analysed by Grant
and Grant (1998) include some Krapina specimens, dated to
130 Ka, which display one of the aforementioned criteria of
hybrid-
isation: high occurrence of an unusual trait in the form of a
rotated
third premolar (36% in these specimens versus a normal rate of
6%
in Neanderthals and AMH). Three specimens from Qafzeh,
along
with Skhul IV and Amud 1 also demonstrate dental anomalies
(Grant and Grant, 1998), and all occur in a supposed region of
con-
tact between H. sapiens and H. neanderthalensis, supporting
their
potential hybrid status.
There are multiple later examples of potential hybrids in Eur -
ope, mostly dating to the period when H. sapiens are known to
be entering this area, allowing for the creation of a hybrid zone.
The specific morphological characteristics are summarised in
Table 3, but here the focus is laid on a few key specimens. The
first
is the well-known ‘hybrid child’ of Abrigo do Lagar Velho,
dated to
24.5 B.P. (Duarte et al., 1999). Despite displaying a mixture of
fea-
tures that led some to conclude it has hybrid status (Duarte et
al.,
1999; Trinkaus and Duarte, 2000), Tattersall and Schwartz
(1999)
have emphasised that this F1-typical (first generation) mixture
is
not to be expected hundreds of generations after initial
hybridisa-
tion, proposed to have occurred around 30 ka (Trinkaus and

60. Duarte, 2000). More refined dating applications suggest that
Nean-
derthals disappeared from Iberia earlier than some radiocarbon
dates had indicated, perhaps as much as 40 ka (Higham et al.,
2006), but they do not affect the point that Lagar Velho is
unlikely
to belong with the first contacts. Holliday (2006) has also
observed
that the existence of F1 hybrids in a hybrid zone is relatively
rare,
which decreases the likelihood of discovering such a rare hybrid
in
the fossil record.
The Vindija specimens, dated to between 33 and 40 ka (Krings
et al., 2000; Higham et al., 2006) are generally accepted as H.
nean-
derthalensis, although some intermediate features could indicate
a
mixed ancestry (Ahern et al., 2002). Some have argued that this
would indicate the presence of hybridisation (Ahern et al.,
2002),
whereas others have commented that individuals such as those
from Vindija could be Neanderthals independently evolving a
mor-
phology similar to that seen in the AMH trajectory (Delson et
al.,
2000). Such homoplasy could have arisen between the two lin-
eages due to phenotypic plasticity, where European Neanderthal
morphology may have been responding to similar environmental
pressures to AMH.
Morphological assessment
As has been noted, morphology is the most common
method for taxonomic assignation in hominin palaeontology.
To reduce or eliminate subjectivity, comparative methods are

61. employed to define levels of expected intraspecific and inter -
specific variation in morphological traits of living species
(Mayr and Ashlock, 1991; Tattersall, 1986; Harvati, 2003).
Although this method is more complicated and results in less
certain conclusions, it is the only relatively objective and satis -
factory method that can be applied to morphology. There is a
clear lack of a closely-related out-group for comparative analy-
ses. Chimpanzees, our closest living relative, do not represent a
valid candidate, due to the large evolutionary gap between
them and hominins and the possibility that they may have
undergone a different pattern of morphological differentiation
(Harvati, 2003).
AMH versus Neanderthals
AMH are more difficult to define in terms of their characteristic
morphology than Neanderthals (Wood and Richmond, 2000).
Table 4 lists some of the anatomical traits that can be used to
dis-
tinguish this morphospecies, yet most of these are defined in
con-
trast to Neanderthals. One example is the uniquely derived
nature
of H. sapiens frontal bone morphology, which can be used to
iden-
tify this group with high levels of accuracy (Arthreya, 2009).
Despite this, Arthreya (2009) has also commented that the high
level of intraspecific variation leads to difficulties in describing
the specific features that make this species so morphologically
distinct.
Tattersall (1986) has suggested that this high level of variation
may in fact be interspecific: that H. sapiens could be an
amalgam-
ation of several separate species, with the ‘archaic’ and
‘anatomi-
cally modern’ groups representing two of these. H. sapiens may

62. be defined by symplesiomorphic, not synapomorphic features
(Tattersall, 1992), and would therefore be cladistically
unclassifi-
able. In the light of this possibility, the belief that H. sapiens is
actu-
ally a subspecies could be seen as a gross misunderstanding of
the
levels of intraspecific variation that can be contained within one
species.
Neanderthals can be more easily defined and diagnosed using
their distinct morphological traits (Tattersall, 1992), as demon-
strated by the list of Neanderthal characteristics in Table 5.
Gener-
ally Neanderthals are typified by increased robusticity and
prominence of muscle attachment areas, with distinctive pelvis
and rib cage morphology, low crural and brachial indices, and a
particular combination of cranial features including occipital
‘bun-
ning’ and midfacial prognathism. Neanderthals are associated
with
a specific combination of features and distinct general
proportions
and relationships between cranial areas (Tattersall and
Schwartz,
1998), with the craniofacial differentiation in comparison to
AMH being considered by some to correspond to species status
(Harvati et al., 2004). Tattersall (2007) has even stated that this
group is the most clearly demarcated extinct hominid group
known as of yet, which would explain the frequent accurate
differ-
entiation of this group from other hominins by morphological
assessment (Harvati, 2003).
This evidence would corroborate the classification of Neander -
thals as a separate morphospecies (Harvati, 2003). Despite this,

63. the question remains as to whether the listed traits are synapo-
morphic, autapomorphic or symplesiomorphic. Tattersall (1992)
and Kimbel (1991) have argued for the highly autapomorphic
nat-
ure of Neanderthals. Demonstrably derived features include
aspects of the bony labyrinth (Spoor et al., 2003), general faci al
morphology (Rak, 1993), and the mandibular fourth premolar
(P4) (Bailey, 2002; Bailey and Lynch, 2005). In these three
cases
AMH bear closer resemblance to Homo erectus than
Neanderthals
do. The case is even stronger for the derived nature of
Neanderthal
elbow morphology, with AMH morphology being more similar
to
that of the australopithecines (Yokley and Churchill, 2006).
Neanderthals inevitably retain some symplesiomorphic fea-
tures, for instance large supraorbital tori, a low cranial vault
(Santa Luca, 1978) and aspects of the pelvis (Rak, 1993). These
are not unexpected, and evidence evolutionary relationships
such
as those between Neanderthals and the Steinheim and Sima de
los Huesos specimens (Wood and Richmond, 2000; Tattersall,
2007). The characteristics shared with AMH merely demonstrate
their relationship as sister taxa and the fact that they were
gener-
ally synchronic and sympatric groups (Holliday, 2003), and
there-
fore could be homoplastic (Stringer and Andrews, 1988). This
point
is also indicated by the large amount of intraspecific variation
found in both groups (Tattersall and Schwartz, 2006; Arthreya,
2009), which vary over a wide range, with minimal overlap

64. S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50 37
(Harvati, 2003) yet maintain distinctly different means
(Tattersall
and Schwartz, 1998). Comparisons with other closely-related
mammalian species show that minimal differentiation and large
overlap in hard-tissue characteristics are the norm (Tattersall,
1986; Tattersall and Schwartz, 1998), with differences between
subspecies of primates being comparatively tiny (Tattersall,
1986).
The morphological evidence leads to one conclusion, that Nean-
derthals and AMH represent distinct species. Neanderthals in
par-
ticular are a distinctive, cohesive evolutionary group (Santa
Luca,
1978; Tattersall and Schwartz, 1998). The most important point
to note is the clear hiatus between the Neanderthal and AMH
mor-
phologies (Santa Luca, 1978). The comparative difference
between
Neanderthals and AMH is at least as great as that between
closely-
related extant species (Tattersall, 1986), and in the case of
cranio-
dental evidence, larger (Tattersall, 1992). Harvati’s comparison
of
intraspecific and interspecific variation with chimpanzee
species
has led to a similar conclusion: the difference between Neander -
thals and AMH is greater than AMH intraspecific variation, and
greater than the distance between Pan paniscus and Pan
troglodytes
(Harvati, 2003). As the majority of morphological change in a
line-

65. age is expected to arise after the true speciation event, even
incip-
ient Neanderthal features would be sufficient to conclude
separate
species status (Rak, 1993).
Genetic evidence
Enormous progress has been made in the last twenty years in
the recovery of genetic evidence from bone (Pääbo, 2003; Green
et al., 2006, 2010; Valdiosera et al., 2006; Meyer et al., 2012;
Dabney et al., 2013), considerably reshaping views of human
evo-
lution through the last half million years. There remain
numerous
problems associated with DNA studies into Neanderthal
introgres-
sion, although it must be admitted that very rapid progress in
development of techniques will much reduce these. Obvious
sources of error include contamination from modern human
DNA, which is pervasive in archaeological remains (Serre et al.,
2004; Serre and Pääbo, 2006), and exacerbated by the damaged
nature and small samples of Neanderthal DNA (Green et al.,
2009). This difficulty is coupled with the overwhelming
similarity
of Neanderthal and AMH DNA (Serre and Pääbo, 2006; Green
et al.,
2008, 2009), often leading to AMH-like DNA sequences being
taken
as evidence of contamination rather than introgression (Serre et
al.,
2004).
DNA analyses depend on estimates of the population size of the
invading H. sapiens population (Forhan et al., 2008) and genetic
diversity, both of which may have been variable and are
difficult

66. to estimate (Wall, 2000). There is a high probability that both
Neanderthals (Orlando et al., 2006; Dalén et al., 2012) and
AMH
(Loogväli et al., 2009; Wall et al., 2009) underwent significant
pop-
ulation and genetic bottlenecks, which could explain the
reduced
genetic diversity of later Neanderthals (Krings et al., 2000;
Serre
and Pääbo, 2006), although the results of the study of Lalueza-
Fox et al. (2005) would contradict this bottleneck hypothesis.
Alves et al. (2012) have even suggested that admixture would
have
a significant effect on such estimates of AMH demography.
Issues also exist in the data sets used, as most comparative
AMH
DNA is from modern individuals, yet later effects such as drift
and
genetic ‘swamping’ could eliminate traces of earlier
introgression
(Serre and Pääbo, 2006), so that larger samples of Upper
Palaeolith-
ic AMH DNA would be required for gaining a more balanced
pic-
ture (Nordberg, 1998; Serre et al., 2004). It is unlikely that we
shall retrieve sufficient DNA from the common ancestral
species
(Lindahl, 1997; Krings et al., 2006) which limits us to
estimations
of the symplesiomorphic genome. Early samples were of small
DNA fragments from few individuals (Serre and Pääbo, 2006),
which could affect estimates of genetic diversity (Briggs et al.,
2009), yet the recent application of a high coverage method
(Max
Planck Institute for Evolutionary Anthropology, 2013) also

67. employed by Meyer et al. (2012) for Denisovan material, could
resolve this issue in the future.
As in morphological analysis, single genetic synapomorphies
can theoretically be used to define phylogenetic relationships,
but this is only possible in rare situations (Knight, 2003),
necessi-
tating in-depth study to reveal interactions between
Neanderthals
and AMH. The identification of hybridisation through DNA
analysis
is theoretically possible, with hybrid DNA showing different
diver-
gence times in comparable regions of the genome (Lalueza-Fox
et al., 2012), yet can be complicated by numerous factors,
which
are treated here briefly.
Mitochondrial DNA evidence
Early genetic studies were based on the analysis of mitochon-
drial DNA (mtDNA). MtDNA is particularly useful for ancient
DNA studies due to its relative abundance and increased
likelihood
of retrieval (Endicott et al., 2010), as well as the fact that it is
maternally inherited (Giles et al., 1980) and thus non-
recombining
(Green et al., 2008; Lalueza-Fox et al., 2012). MtDNA from no
less
than 22 Neanderthals (Krings et al., 1999; Scholz et al., 2000;
Ovchinnikov et al., 2000; Schmitz et al., 2002; Beauval et al.,
2005; Lalueza-Fox et al., 2005, 2006; Caramelli et al., 2006;
Noonan et al., 2006; Orlando et al., 2006; Serre and Pääbo,
2006;
Green et al., 2008; Briggs et al., 2009), and 8 AMHs (Scholz et
al.,

68. 2000; Caramelli et al., 2003; Serre et al., 2004; Pettitt, 2011)
has
been analysed. Most compare Neanderthal evidence with
modern
mtDNA, but signals of admixture may have been affected by
later
genetic bottlenecks and drift, necessitating comparison with
pre-
historic AMH DNA.
Such studies conclude that Neanderthal DNA clusters to the
exclusion of modern humans (Krings et al., 2000; Knight,
2003),
with the overall difference between the two populations being
three times as great as the intraspecific mtDNA variation for
mod-
ern humans (O’Rourke et al., 2000; Tetushkin, 2001) and half of
that between modern humans and chimpanzees (O’Rourke et al.,
2000). This finding leads to the conclusion that no introgression
occurred (Tetushkin, 2001), supported by the lack of any direct
evi-
dence of introgressed genes.
If the absence of evidence of introgression is a true refl ection of
the prehistoric situation, it would limit the possible amount of
admixture that occurred (Krings et al., 2006), with maximum
esti-
mates ranging from 0.1% to 25% (Forhan et al., 2008) and
minimum
estimates of 0 (Ghirotto et al., 2011). Yet there are many issues
associated with mtDNA analyses, including frequent
introgression
of mtDNA across species boundaries (Barton, 2006),
dependencies
on estimates of mutation rates (Hawks, 2006), and questionable
claims of the selective neutrality of mtDNA (Nordberg, 1998;

69. Hawks, 2006). A negative consequence of the maternal
inheritance
of mtDNA is that such sequences cannot reveal the entire evolu-
tionary history of a population (Templeton, 2005), meaning that
nuclear DNA analyses are required to corroborate the
conclusion
of an absence of Neanderthal–AMH admixture (Beerli and
Edwards, 2002; Lalueza-Fox et al., 2012).
Nuclear DNA evidence
The main results of the Neanderthal genome study were first
published by Green et al. (2010), who used a new measure, the
D
statistic, and concluded that introgression of Neanderthal genes
into the AMH genome of between 1.3% and 2.7% must have
occurred due to the fact that Neanderthal DNA was closer to
that of non-Africans than to that of Africans. They argue that,
as
Table 3
Review of possible Neanderthal –AMH hybrids.
Site Date H. neanderthalensis features H. sapiens features
Intermediate/anomalous
features
Taxonomic
assignation
Cioclovina,
Romania
29–210 kya (33.2–

70. 33.8 kya BP cal)q
– Supraorbital torih,o
Suprainiac fossap,q
– Nuchal torusp,q
– External occipital
protuberanceq
– Occipital ‘hemi-bun’p
– Supraorbital tori not
continuousq
– Superior nuchal lines (position
and size)q
– High, vertically rising frontal
squamah
– Prominent glabellah
– High and rounded cranial
vaulth,q
– No anterior mastoid tubercleh
– Small juxtamastoid eminenceh,q
– Narrow digastrics fossah
– Well-developed superior nuchal
lineh

71. – No suprainiac fossah,q
– Laterally and inferiorly
prominent mastoid processq
– Coronal outlineq
H. sapiensh,q
Abrigo do Lagar
Velho, Portugal
25.6 kyaf – Juxtamastoid eminencei
– I2 shovelling
i
– Suprainiac fossai
– Juxtamastoid eminencef
– Posterior retreat of
mandibular symphysisf,i
– Dental maturational patternc
– Anterior symphyseal
configuration of the mandiblef
– Femoral midshaft
circumference versus lengthf
– Proximal humeral diaphyseal
morphologyf
– Strongly developed pectoral

72. musclesf
– Short, stout legsr
– Backwards sloping of
mandibler
– Limb segment proportionso
– Development of ‘‘chin’’f,r
– I2 breadth
f
– Breadths of I2 versus Ms
f
– Anteromedial position of radial
tuberosityf
– Little lateral curvature of the
radiusf
– Small front teethr
– Short facer
– Minimal brow developmentr
– Narrow anterior pelvisr
– Size of juxtamastoid
processf
– Size of mastoid processf

73. – Hybridf,r
– Possible
hybrid?k
– H. sapiensc
Mladeč 1 and 2
(females)
31 kyat – Pronounced occipital ‘bun’t
– Distinctive nuchal areat
– Large juxtamastoid
eminencesp
– High foreheadt
– Reduced browst
– Small facial dimensionst
– H. sapiens?d,t
Mladeč 3 (infant) 31 kyat – Thick, well-developed medial
brow ridgesj
– Prominent glabellaj
– Strongly developed occipital
bunj,p
– Low occipital heightj
– Lambdoid flatteningj

74. – Short occipital plane lengthj
– Short and low temporal bonej
– Prominent juxtamastoid
eminencej
– Shape of orbitj
– Degree of frontal vaultingj
– Antero-superior orientation of
the external auditory meatusj
– Strongly concave glenoid fossaj
– Post-glenoid tuberclej
– Flat squamous temporalj
– Nuchal plane lengthj
– Occipital breadthj
Hybridj
Mladeč 6, 7 and 9
(males)
31 kyat – Small mastoid processesg
– Lateral profileg
– Elliptical suprainiac fossaeg
– Shallow groove on inferior

75. nasal marginsg
– Cranial height/length indexg
– Cranial breadthg
– Nasion projectiong
– Glabella projectiong
– ‘Square’ parietal bonesg
– Occipitomastoid crestg
– Supraorbital projectiong
– Supraorbital sulcusg
– Divergence of the temporal lineg
– Parietal thicknessg
– Occipital plane lengthg
– Mandibular fossag
– Strongly curved frontal boned
– Vertical heightg
– Supraorbital torus
structureg
– Occipital (biasterionic)
breadthg

76. – Possible
hybrid?g
– Not hybridd
Pes�tera cu Oase,
Oase 1
(mandible)
34–36 kyas – Unilateral bridging of
mandibular forameno
– Mesial mental foramens
– Narrow lateral corpuss
– Absence of retromolar spaces
– Symmetrical mandibular
incisuress
– Lateral incisures crests
– Small superior medial pterygoid
tubercles
– Lingual bridging of the
mandibular foramens
– Distal molar megadontias
H. sapienss
38 S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50

77. Table 3 (continued)
Site Date H. neanderthalensis features H. sapiens features
Intermediate/anomalous
features
Taxonomic
assignation
Pes�tera cu
Oase,Oase 2
(cranium)
36 kyal – Sagittal frontal arc (long and
flat) l,p
– Large juxtamastoid eminencel
– Large buccolingual and
mesiodistal diameters of
molarsl
– Molar size progressionl
– Occipital ‘hemi-bun’p
– Overall cranial proportionsl
– Subrectangular orbitsl
– Infraorbital regions –
pronounced canine fossael
– Modest superciliary archesl

78. – Narrow nasal aperturel
– No anterior mastoid tuberclel
– High, rounded parietal regionl,p
– Pentagonal contour in norma
occipitalisl
– Unsure, possible
hybridl
Pestera Muierii,
Muierii 1
36 ky BP (cal)m – Frontal curvature of the
neurocranial vaultm
– Shallow transverse suprainiac
fossa m
– Median nuchal torusm
– Lacks retromolar spacem
– High coronoid processesm
– Asymmetrical notchesm,p
– Breadth/height index of
scapular glenoid fossam
– Moderately low frontal arc of
craniumm

79. – Occipital ‘bun’p
– Small superciliary archesm
– Deep canine fossaem
– Anterior zygomatic roots above
M12
c
– Modest nasal aperture breadthm
– Dentitionm
– Scapulam
– Marked projection of the
occipital bunm
Possible hybrida,m
Vindija, G1 29–210 kyab – Reduced midfacial
prognathismb
– Reduced nasal breadthb
– Thinner cranial vaultsb
– Incipient chinsb
– Reduction and shape
changes in supraorbital
torusb
– Scapular glenoid fossae

80. – H.
neanderthalensis?b
– Possible hybridb
a Ackermann (2010).
b Ahern et al. (2002).
c Bayle et al. (2010).
d Bräuer et al. (2006).
e Di Vincenzo et al. (2012).
f Duarte et al. (1999).
g Frayer et al. (2006).
h Harvati et al. (2007).
i Holliday (2003).
j Minugh-Purvis et al. (2006).
k Quintyn (2009).
l Rougier et al. (2007).
m Soficaru et al. (2006).
n Soficaru et al. (2007).
o Trinkaus (2005).
p Trinkaus (2007).
q Trinkaus and Duarte (2000).
r Trinkaus et al. (2003).
s Wild et al. (2005).
t Wolpoff et al. (2006).
S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50 39
Neanderthals are equally related to Chinese, Papua New
Guineans
and French, introgression must have occurred in the Middle
East.
Neves and Serva (2011) subsequently argued that the results
need

81. to be replicated before they can be accepted, preferably with
larger
samples of Neanderthal and Upper Palaeolithic nDNA, in view
of the
contradictory mtDNA evidence (Tetushkin, 2001; Krings et al.,
2006). Nuclear DNA from the Vindija specimens had been
analysed
previously (see Serre et al., 2004; Noonan et al., 2006),
however
studies failed to find evidence of introgression.
An alternative explanation for Green et al.’s results might be
that of ancient population substructure in AMH populations
before
they left Africa (Lalueza-Fox et al., 2012), with the African
subpop-
ulation that later gave rise to the dispersing AMHs sharing a
longer
ancestry with Neanderthals (Ghirotto et al., 2011). This point
has
been acknowledged by Green et al. (2010) and supported by the
research of Wall et al. (2009) and analysis of the Xp21.1 gene
(Garrigan et al., 2005). Durand et al. (2011) suggested that the
D-
statistic would be confounded by such a population history, but
conclude that admixture is a more parsimonious possibility than
population substructure for the results of Green et al., and con-
clude that tests could be used to eliminate substructure as an
explanation. Similarly, Lohse and Frantz (2013) used a
maximum
likelihood method to reject population substructure as a cause
of
the genetic signatures found. Sankararaman et al. (2012) have
made the lucid argument that, if interbreeding did occur after
Neanderthals and AMH diverged, then genes would have been
exchanged after �100 ka. If the substructure argument was

82. valid,
the date of the last genetic exchange would be closer to the date
of common ancestry, around 230 ka (Sankararaman et al.,
2012).
As can be seen, there are ways to eliminate the explanation of
sub-
structure in this debate.
Many studies published since Green et al.’s (2010) paper have
shown supporting evidence of introgression, frequently using
divergent haplotypes (e.g. Abi-Rached et al., 2011) or patterns
of
Table 4
List of AMH morphological characteristics.
Location Trait
Cranial
traits
Calvarium Globular braincaseg
Short, high craniumf
Long, high parietal archf
Parietal arch – narrow inferiorly, broad
superiorlyf
High frontal archf,g
Rounder frontal bonesa

83. Thin bones of cranial vaulte
Upper facial
region
Discontinuous supraorbital torif
Reduction of supraorbital toria,e,g
Curved occipital bonef,f
Orthognathye
Nasal region Shorter nasion bregma chorda
Mandible Mental eminence (chin)f,g
Thin bone of mandibular bodye
Dental Anterior teeth Canine fossag
Postcanines Perfect oval shape of mandibular P4
b
Wide lingual crown of mandibular P4
b
Simplified occlusal morphologyg
Reduced crownsc,g
Reduced root sizec
Symmetrical lingual crown contourg
Absence of transverse crestg

84. Absence of accessory ridges and fissuresg
Reduction in number of cusps and rootsg
Absent or reduced metaconid forming a
lingual shelfg
Postcranial Trunk Narrow trunkg
Limbs Elongated distal limbsg
Long limbs relative to trunkg
Small humeral bi-epicondylar breadthsh
Pelvis Short, stout pubic ramus with rounded cross-
sectiond
Narrow pelvisg
General Low body mass relative to statureg
Loss of robusticitye,g
a Arthreya (2009).
b Bailey and Lynch (2005).
c Kupczik and Hublin (2010).
d Rak (1990).
e Stringer and Andrews (1988).
f Tattersall (1992).
g Wood and Richmond (2000).
h Yokley and Churchill (2006).
Table 5
List of Neanderthal morphological characteristics.

85. Location Trait
Cranial traits Calvarium Smoothly rounded cranial profile from
rear
view (‘en bombe’)g,m,n,p
Lower cranial vaultd
Shorter, wider occipital planed
Suprainiac fossae,g,j,m,o,p
Rounded, laterally projecting parietal boner
Lambdoid flatteningo
Anteriorly placed lambdae
Occipital ‘bun’ (posteriorly projecting
occipital)o,q,r
Horizontal occipital torus of uniform
thicknessj,m
Occipital torus restricted to central part of
occipital bonej,m
Angling along anterior squamosal suturen
Pronounced juxtamastoid eminenceg
Large juxtamastoid crestm
Smaller mastoid processd

86. Rounded mastoid protuberancej,m
Occipitomastoid process P mastoid process j,o
Upper facial
region
Thick, double arched supraorbital torio,q,r
Supraorbital tori continuous across the
glabellao
Inferomedially truncated orbitsn,p
Retreating zygomatic profilem,n,r
Long, thin zygomatic archesp
Pronounced midfacial prognathismd,g,m,r
Nasal region Well-developed medial projection of internal
nasal margink
Swelling of lateral nasal cavitywallk
Capacious nasal aperturem,o
Large nasal fossao
Lateral expansion of the frontal sinuseso
Projecting nasal bonesm
Maxilla Underdeveloped mental eminenceo,r
Lack of ossified groove over lacrimal groovek

87. Narrow lower facen,o
Mandible Sigmoid notch crests terminate close to lateral
ends of condylesn
Sigmoid notches deepest in front of low-set
condylen,p
Obliquely truncated gonial anglesn
Inferior, lateral position of articular eminenced
Mental foramen under first mandibular molarr
Thin symphyseal bonep
Cranial base Wide sphenoid anglem
Highly pneumatised petrosal bonen,p
Long, narrow, ovoid foramen magnumn,p
Pronounced juxtamastoid eminenceg
Large juxtamastoid crestm
Smaller mastoid processd
Rounded mastoid protuberancej,m
Occipitomastoid process P mastoid processj,o
Bony
labyrinth

88. Anterior
semicircular
arc
Relatively small and narrowl
Narrow in width relative to heightl
Posterior
semicircular
canal arc
Relatively smalll
Positioned more inferiorly relative to lateral
canal placel
Lateral
semicircular
arc
Absolutely and relatively largel
Ampular line More vertically alignedl
Dental Anterior
teeth
Broad anterior teetha,h,m,r
Shovelled incisorsa,f,h,r
Prominent lingual tuberclesa
Labial convexitya,f

89. Postcanines Relatively thin enamelh
Retromolar spaceg,m,o,q,r
Complex occlusal surfacesa,n,p
Mid-trigonid crest more frequenta,f
Inwardly sloping centroconids and
centroconesn
Extra fissures, ridges and lingual crestsa
Larger crown baseh
40 S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50
linkage disequilibrium (e.g. Hammer et al., 2011) to infer
admix-
ture with ancient populations. We now have a much more
broadly
based view of our genetic ancestry; Mendez et al.’s (2012)
study
shows that the derived STAT2 haplotype, a potential candidate
of
introgression, was ten times more likely to be found in Papua
New Guineans than in other groups, Wall et al. (2013) argue
that
Neanderthal genes are more prevalent in East Asians than
Europe-
ans, while Hammer et al. (2011) believe that their genetic
analysis
is indicative of introgression with a previously unknown transi -
tional hominid from Central Africa. In addition to these
geographic
regions, we now have potential evidence of secondary introgres -

90. sion (i.e. from an AMH population carrying introgressed genes)
in
North Africa (Sánchez-Quinto et al., 2012) and East Africa
(Wall
et al., 2013). A new interpretation is that our African ancestry
was mosaic in nature, with potentially multiple as yet un-
defined
hominins contributing to our modern genome (Hammer et al.,
2011; Stringer, 2012). Comparisons can be drawn with the idea
of population subdivision, as these hominins may represent the
beginnings of subspecies division, while being insufficiently
differ-
entiated to warrant full species status.
The assumption that divergent haplotypes or specific patterns
of linkage disequilibrium are indicative of introgression needs
to
be validated. Such signals could arise from other processes such
as fixation of genes or incomplete lineage sorting (Alves et al.,
Table 5 (continued)
Location Trait
Large root canalsh,r
Longer rootsh
Enlarged pulp chambers (‘taurodontism’)a,f,h
Mandibular
P4
Strong, continuous transverse cresta,b

91. Well-developed, medially placed metaconida
Truncated mesiolinguallobea,b
Narrow lingual crownb
Asymmetrical crown shapea,b
Postcranial Trunk Large dorsal sulcus on scapulaem
Long scapulaen
Expanded rotator cuff attachmentsn
Well-marked muscle attachments alongs
capulaer
Long, narrow glenoid fossaen
Long clavicles with flattened shaftsn,q,r
Flaring iliac bladesn
Ribcage is narrow at top and flares out and
downn
Broad ribcageq,r
Mobile vertebral column set against inferiorly
placed sacrumn
Reduced vertical length of the waistn
Limbs Pronounced radial curvaturem

92. Thick corticesn
Restricted medullary cavitiesn
Expanded articular surfacesn
Robust limb bonesq,r
Well-developed muscle attachmentsr
Short distal extremities resulting in low
brachial and crural indicesq,r
Bowing of femorar
Low humeral torsion angles
Narrow humeral deltoid tuberositiesc
Robust humeral diaphysisc
Large, transversally humeral headsc
Enlarged epiphyses with large articular
surfacesc
Large olecranon fossaec,s
Humeral medial and lateral pillars that are
distodorsally smalls
Hands and
feet
Flattened first carpometacarpal jointm,r
Elongated polluxm

93. Long pollical distal phalanxr
Large carpal tunnelsn
Expanded pollical and ulnar distal phalangeal
tuberositiesn
Accentuated muscle attachment areasn
Robusticityr
Pelvis Wide pelvisr
Long, plate-like superior pubic ramusi,m,n,r
Anteriorly placed sacrumr
Anteriorly placed pelvic inleti
Triangular shaped ishiopubic regioni
Obtuse subpubic anglei
Internal obturator groove encroaches upon
ischial tuberosityi
a Bailey (2002).
b Bailey and Lynch (2005).
c Churchill and Smith (2000).
d Harvati (2003).
e Harvati et al. (2007).
f Hershkovitz et al. (2011).
g Holliday (2003).
h Kupczik and Hublin (2010).
i Rak (1990).

94. j Santa Luca (1978).
k Schwartz and Tattersall (1996).
l Spoor et al. (2003).
m Tattersall (1992).
n Tattersall (2007).
o Tattersall and Schwartz (1998).
p Tattersall and Schwartz (2006).
q Wood and Lonergan (2008).
r Wood and Richmond (2000).
s Yokley and Churchill (2006).
S. White et al. / Journal of Anthropological Archaeology 35
(2014) 32–50 41
2012), and do not exclude the possibility of ancestry. The use of
chimpanzee DNA as an ancestral comparison merely shows that
the derived states could have evolved any time after the diver -
gence with our common ancestor (Lowery et al., 2013). A recent
study has demonstrated the plausibility of genetic drift and
demic
diffusion in creating a cline of introgression from Europe to
Asia,
which could otherwise be interpreted as differing levels of
hybrid-
isation (Lowery et al., 2013). It is doubtful that we will be able
to
overcome the inherent assumptions of modern genetic studies
without the retrieval of DNA from specimens ancestral to both
Neanderthals and AMH. With luck this could be possible, given
the successful retrieval of DNA of a cave bear (Ursus deningeri)
from
Sima de los Huesos, dated to �400 ka (Valdiosera et al., 2006;
Dabney et al., 2013), but future research would be constrained
by the decreasing size of DNA fragments which can be retrieved
as the age of the specimen increases (Valdiosera et al., 2006).

95. In addition to the Neanderthal draft genome, we now have
genetic evidence from the phalanx found in Denisova cave,
dating
to �40 ka (Krause et al., 2010). It has been suggested that this
spec-
imen represents a sister group to the Neanderthals, splitting off
around 465 ka (Krause et al., 2010). Original analysis of
recovered
nuclear DNA suggested introgression with Melanesians at a
level of
approximately 4.5%, which is presumed to have taken place
after
the admixture event between Neanderthals and AMH (Reich
et al., 2010). A recent study was able to produce a high
coverage
sequence from the same specimen (Meyer et al., 2012), a
finding
which has clear implications for the future of the hybridisation
debate. With evidence of such a complicated genetic history of
our species, most probably fraught with extensive reticulation
over
a significant period of time, it is clear that the question of
Neander-
thal–AMH hybridisation is far more intricate than previously
anticipated.
Models of admixture
Some have attempted to model the levels of admixture that
could result in such seemingly contradictory evidence between
mtDNA and nuclear DNA. For instance, Currat and Excoffier
(2004) concluded a maximum estimate of 34–120 admixture
events in the entire 12.5 ka estimated period of admixture,
corre-
sponding with a maximum level of introgression of Neanderthal
genes at 0.02–0.09%. This estimate does not match the results

96. of
Green et al. (2010), although a later Neolithic expansion of H.
sapi-
ens could have led to a decrease in the existing signal, as could
dilution effects and genetic drift (Currat and Excoffier, 2004).
A
later model estimated interbreeding success rates to be below
2%, which would result in low levels of introgression in mtDNA
evi-
dence (Currat and Excoffier, 2011). This would predict the
disparity
between the mtDNA and nuclear DNA evidence, but is
dependent
on the accuracy of the estimates of the period of admixture.
Another relevant model is that of Belle et al. (2009), who used
coalescent theory to compare Neanderthal, AMH and modern
human information with simulated genealogies. This work
resulted in a best estimate of no admixture between Upper
Palae-
olithic populations, with a maximum level of 0.001%
interbreeding
per generation. There are thus obvious incongruities in the
predic-
tions of different models which could negate their efficacy in
this
debate. For instance Hawks and Wolpoff (2006) found that the
null
hypothesis of no introgression could not be rejected, but that
the
variation found was within the expected range for a
subpopulation
connected by gene flow, thus refuting the assignation of
Neander-
thals to a separate species.

97. A recent model developed by Eriksson and Manica (2012)
explored the effect of ancient population substructure. Their
model
fitted the genetic results more closely than Green et al.’s
proposal,
again showing that we cannot accept the conclusion of
hybridisation
Table 6
Summary of mtDNA analyses of Neanderthals and AMH.
Age (kya) Results Reference
Neanderthals La Chapelle aux Saints No introgression Serre and
Pääbo (2006)
Engis 2 No introgression Serre and Pääbo (2006)
Feldhofer 1 40 No introgression Briggs et al. (2009)
Feldhofer 2 40 No introgression Briggs et al. (2009)
Krapina 110–100 No introgression Scholz et al. (2000)
Mezmaiskaya 1 60–70 No introgression Briggs et al. (2009)
Mezmaiskaya 2 41 No introgression Briggs et al. (2009)
Mezmaiskaya? 29.2 No introgression Ovchinnikov et al. (2000)
Monte Lessini 50 No introgression Caramelli et al. (2006)
Neandertal NN 1 40 No introgression Krings et al. (1999),
Schmitz et al. (2002)
La Rochers de Villenueve (RdV1) 40.7 No introgression
Beauval et al. (2005)
Scladina cave 100 No introgression Orlando et al. (2006)
El Sídron 44 No introgression Lalueza-Fox et al. (2006)
El Sídron 441 40 No introgression Lalueza-Fox et al. (2005)
El Sídron 1253 39 No introgression Briggs et al. (2009)
Vindija No introgression Krings et al. (2000)
Vindija (?) 38 No introgression Noonan et al. (2006)
Vindija 33.16 38.3 No introgression Green et al. (2008)