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The Divergence and Development Within the Genus Canis
The Genus Canis is classified under the Class Mammalia, Order Carnivora, and
Family Canidae. The family Canidae contains coyotes, dogs, foxes, jackals, and wolves.
This family is further divided into the genus Canis, containing only the dogs, foxes and
jackals. This genus was described in 1758 by Linnaeus. This was the same year that
Linnaeus described the class Mammalia. The order Carnivora was described by Bowdich
in 1821 while the family Canidae was described by G. Fisher in 1817 (ITIS report).
Members of the family Canidae first developed in the Americas during the
Oligocene period. During the late Miocene the true dogs crossed the Bering land bridge
from North America to Asia. This group spread throughout Europe (Alderton 1994). It
was during this time of dispersal that much of the important development in this group
occurred. The dogs that settled in Asia are believed to be the basis from which modern
foxes and wolves evolved (Alderton 1994). These animals underwent a period of
development in Eurasia after which some moved back across the Bering land bridge to
re-populate the Americas.
The grey wolf, Canis lupus, followed this path approximately 700,000 years ago.
This dispersion allowed the grey wolf to inhabit much of the northern hemisphere. In
addition to the grey wolf, an ancestor of the coyote, Canis latrans, followed a similar path
almost 2 million years ago. With the progression into the Pleistocene, three different
lineages of wolf diverged in North America. These were Canis lupus, Canis rufus and
Canis dirus, the latter being extinct (Alderton 1994).
The genus Canis was described in 1758 by Linnaeus in the 10th edition of
Systema naturae. The description is based on a specimen of Canis lupus. In 1978 Van

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Gelder included Alopex, Atelocynus, Cerdocyon, Pseudalopex, Lycalopex, Dusicyon, and
Vulpes as subgenera in this genus but this form of classification is not accepted by most
mammalogists. The species that are accepted as part of this genus are Canis adustus, C.
aureus, C. latrans, C. lupus, C. mesomelas, C. rufus, and C. simensis (Wozencraft 1993).
The systematics and development of these species will be addressed shortly.
The species that have been classified within this genus were described between
1758 and 1851. C. aureus, the golden jackal, was described by Linnaeus in 1758 in the
10th edition of Systema naturae. Since this description multiple synonyms have been
named for this species (Wozencraft 1993). C. mesomelas, the black-backed jackal, was
described by Schreber in 1775. Few synonyms have been published for this species. In
1914 Heller described them as Canis elgonae and Canis mcmillani. A similar
classification occurred in 1926 when Thomas described a specimen of C. mesomelas
using the synonyms C. achrotes and C. arenarum (Wozencraft 1993).
The simian jackal, C. simensis, was identified by Ruppell in 1840. This species
has not been extensively studied and is sometimes placed in the subgenus Simenia. Along
with this, few synonyms have been encountered for this species, sinus was used by
Garvais in 1855 and walgie by Heuglin in 1863 (Wozencraft 1993).
C. adustus, the side-stripped jackal, was described in 1847 by Sundevall. This
species has not received much attention since the early 1900’s. At his time a few different
synonyms were published. Each of these were alterations at the species level, none of
them placed this species in a different genus (Wozencraft 1993).
The grey wolf, C. lupus, was also described by Linnaeus in 1758. Linnaeus
originally classified this species as Canis familiaris but both of these names were

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published simultaneously. Since then C. lupus has been adopted as the name for these
organisms. As with C. aureus, there have been multiple synonymous names published
over the years for individuals from this species. The occurrence of these synonyms makes
it apparent how often this species has been studied (Wozencraft 1993).
C. latrans, the coyote, was classified in 1823 by Say. This is another species that
has attracted a lot of attention leading to subsequent publishing of multiple synonyms as
multiple individuals conducted their research. In 1951 this species was reviewed by
Young (Wozencraft 1993).
Lastly, C. rufus, the red wolf, was classified by Audubon and Bachman in 1851.
In 1791 Bartram described this species as niger. While this name was widely used it was
declared invalid in 1957 in the International Commission on Zoological Nomenclature.
Multiple parties reviewed and recognized this species in the late 1960’s and 1970’s.
During this time the validity of this classification came into question. In 1976 Clutton-
Brock et al. challenged the validity of classifying rufus as a full species. This was due to
the existence of natural hybrids between rufus and both lupus and latrans. However, in
1971, Paradiso and Nowak suggested that these hybridizations could be a result of habitat
disruption by humans. It was not until 1979 that Nowak published evidence for the
distinctness of rufus (Wozencraft 1993).
The phylogenetic analysis of this genus is still developing today. The use of DNA
sequencing is allowing more detailed examinations to be done that may settle some
conflicts that have been persistent in the past. According to a study done in 1998 by
Gittleman et al. the first divergence occurred when C. lupus and C. latrans moved across

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the Bering land bridge. This resulted in the differential development of the jackals, C.
mesomelas, C. aureus, and C. adustus as these species remained in Eurasia.
It has been mentioned previously that C. davisii is thought to be the species that
gave rise to the coyotes and the wolves. This means that both C. latrans and C. lupus are
descendants of this animal (Alderton 1994). Since records have shown that an ancestor of
C. latrans, C. leptophagus, moved across the Bering land bridge before C. lupus, C. lupus
must have diverged from this group during the developmental period that occurred in
Asia (Alderton 1994). As development for both C. lupus and C. latrans continued after
reaching the Americas it is further hypothesized that a hybridization event occurred. This
hybridization resulted in the development of C. rufus which has characteristics of both
the coyote, C. latrans, and the grey wolf, C. lupus. This is a contested hypothesis
(Gittleman et al. 1998).
C. simensis, the Simian jackal, is found in Africa along with the other jackals but
has been shown to be more closely related to C. lupus and C. latrans then to the other
jackals, C. adustus, C. aureus, or C. mesomelas. Phylogenetic analysis with
mitochondrial DNA has been used to show this relationship (Marino and Sillero-Zubiri
2004). This connection suggests that C. simensis evolved from an ancestor of C. lupus
that crossed into Africa from Eurasia. It is estimated that this development occurred
100,000 years ago. This means that C. simiensis developed from a common ancestor that
is shared with the C. lupus and C. latrans species that moved into the Americas (Marino
and Sillero-Zubiri 2004).
C. aureus, the golden jackal, occurs in a range similar to that of C. adustus, and C.
mesomelas. While the distribution is similar as well as some of their behavior the skull of

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this species has been shown to be more similar to those of C. lupus and C. latrans. The
skull also varies from that of C. simensis (Jhala and Moehlman 2004). This suggests that
C. aureus diverged from an ancestor of C. lupus and C. latrans much as C. simensis did.
Since there is a notable difference between the skulls of C. simensis and C. aureus it is
unlikely that C. aureus would have developed from these species.
C. mesomelas, the black-backed jackal, is also found in Africa along with C.
adustus, the side-striped jackal. These species are generally differentiated from one
another by their morphology and coloration. C. mesomelas has a dark patch of fur on its
back resembling a saddle as well as reddish flanks and limbs, all of which are absent in
C. adustus (Loveridge and Nel 2004). C. adustus, on the other hand, is larger than C.
mesomelas and has a white stripe on its flanks as well as a characteristic white-tipped tail.
While the systematics and phylogeny of this genus has been contested the ecology
of those species included has often been reviewed due to conflicts with humans or risk of
extinction. Some of these species have been studied because they have been disturbed by
human movements while others have attracted the attention of researchers by dwindling
in numbers to the point that extinction is a realistic possibility. In the case of extinction
many pursue research goals quickly so as to preserve a record for the future should the
species be lost and also to attempt and find a way to conserve what population remains.
C. mesomelas is distributed throughout East and South Africa but is absent in the
equatorial region. This type of distribution is common in species adapted for the dry
conditions present in these areas. The preferred habitat contains dry Acacia bush and
savannah. These jackals are widespread and are common wherever there is suitable
habitat. They also occur in many ranch areas in this region which has led to their

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classification as a pest. This has resulted in pest management measures but the population
has managed to survive in spite of these local difficulties. While they have a preferred
environment, these animals are found in many habitats including coastal deserts,
grasslands, savannah and farmland. They tend to avoid dense vegetation that would
hinder their scavenging.
The habitat used is also affected by the presence of other species. When C.
mesomelas is sympatric with C. adustus it will use open grasslands more frequently while
occupying wooded savannah when sympatric with both C. adustus and C. aureus
(Loveridge and Nel 2004). When sympatric with these species C. mesomelas will run C.
adustus out of the grassland areas.
They are opportunistic feeders and will eat anything. This makes them very
versatile when it comes to harsh environments since they will hunt any small to medium
sized mammal as well as reptiles, birds, carrion and human trash. They will forage in
small groups or pairs. A pair bond that is formed for life between mating pairs is often the
basis of these groups. These pairs will defend a permanent territory and raise one to six
pups in a breeding season. There are numerous records of alloparental care but the pups
that disperse from the natal range can travel more than 100km. Their predators include
leopards, spotted hyenas and many birds of prey as well as other jackals that may attack
pups if left unattended. They are also hunted in some areas for their fur but this is not a
widespread behavior (Loveridge and Nel 2004).
C. aureus is distributed throughout North Africa, the Arabian Peninsula, western
Europe, Turkey, Syria, Iraq, Iran, central Asia and India. Their range also extends into Sri
Lanka, Thailand and parts of Indo-China. They are common wherever there is abundant

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food and cover. Since this is an omnivorous species they can survive in a number of
habitats ranging from deserts to evergreen forests. Like C. mesomelas, they are
opportunistic and will forage near humans. Their diet commonly includes rodents,
lizards, snakes, birds, hares and Thomson’s gazelle with variations depending on the prey
available in the given area. They will often hunt alone, depending on their hearing to
locate prey. They will also form smaller packs that allow them to take larger game. Their
social behavior is also similar to C. mesolmelas (Jhala and Moehlman 2004).
C. simensis is found in the Ethiopian highlands above the tree lines. They are
restricted to Afroalpine grasslands and mountain grasslands. Their preferred habitat
contains short herbaceous and grassland plants that provide abundant rodent populations.
Other habitat types that exist in these areas are utilized as well so long as they support a
large rodent population since more than 96% of their diet is rodent based. Individuals in
this species often hunt alone but will form small packs so as to hunt larger game. They
have been recorded moving among herds of cattle, using the herd as cover to ambush
rodents. While sometimes hunting alone these wolves do live in packs and will defend a
territory as a cohesive unit. The dominant female of the pack will reproduce once a year
and the entire pack will aid in providing for the pups (Marino and Sillero-Zubiri 2004).
C. rufus can only be found in North Carolina where populations have been
reintroduced. Their historical range included much of the south-eastern United States.
Little is known about their preferred habitat since little research was done before their
range was drastically reduced. It is generally thought that they would occupy a number of
habitats and would be able to thrive wherever there was ample prey. Their dominant prey
is small mammals such as rodents and rabbits. They are primarily nocturnal hunters and

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will forage individually and in packs. They live in extended family packs similar to those
of C. lupus with a dominant, breeding pair and exhibit the same parental care as the other
canids (Beyer, Kelly and Phillips 2004).
C. latrans is thought to have had a historical range consisting of the south-west
plains of the United States and Canada and the central and Northern regions of Mexico
before European settlement. They expanded north and west as land was converted by
humans and the wolves were eliminated. They can survive in any habitat with a proper
amount of food and are opportunist and generalist predators. Their foraging habits change
with the region and prey availability. As with the other canids they will hunt smaller
animals alone but rely on the pack to pursue larger game. Their social structure is not like
that seen in C. lupus, which will be discussed shortly. There is a alpha pair that may share
a bond for a few years but not necessarily for life. Pups that are raised may or may not
stay with the group. As with the other related species, they are territorial and will defend
and mark their territory (Bekoff and Gese 2004).
C. lupus was historically the most widely distributed mammal in the world. It
once lived throughout the northern hemisphere but has since become extinct in much of
Europe, Mexico and the United States. Today they occur primarily in remote wilderness
areas. They can survive in all northern habitats where there is a suitable supply of food.
They will prey on a variety of species, many of them being larger mammals such as
moose and caribou. They will also eat smaller prey if it is available. They will hunt in
their family packs in the winter but forage alone or in smaller groups during the summer
months. They are capable of maintaining extended chases but will often prey on sick or

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injured animals, removing the weak from the herds. Their social behavior consists of a
family pack with a dominant breeding pair (Boitani and Mech 2004).
C. adustus is distributed from Senegal to Somalia and regions of South Africa.
They prefer the deciduous woodlands of many savannahs. This provides wooded habitat
as well as bush, grassland and marshes which are good hunting territories for these
animals. These jackals are nocturnal predators that mainly feed on small mammals,
insects and fruit. Although these animals live in pairs they will often join together in
small troops to hunt. Reproduction occurs annually just before the rainy season with three
to six pups in each litter (ThinkQuest 1998).
While some species in this genus have held the attention of both the public and
the scientific communities for decades or longer, others have gone mostly unnoticed.
Because of this, there are a number of current projects that are attempting to fill in these
knowledge gaps so as to aid conservation efforts or, in the worst case, preserve a record
of the species before they are lost to extinction. The most prevalent research projects
involve the ecology and behavior of these different species and the transmission of
different pathogens. There are also multiple projects concerning predator-prey
relationships and the effects of human land use on the survival of some of these species.
While these are investigative studies others are being conducted to simply gather facts
about the species and record as much information about them as possible (Loveridge and
Nel 2004, Gese and Bekoff 2004, Marino and Sillero-Zubiri 2004, Jhala and Moehlman
2004, Beyer, Kelly and Phillips 2004).
The development and classification of the members of this genus continues to be
a point of interest for many in the scientific community. While these animals often hold

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important roles in their habitats many have experienced some degree of persecution by
humans or loss of habitat due to human development and dispersal. Current research
efforts are aimed at gaining a better understanding of these animals and how they relate
to their environments. This research is also being used to plan conservation strategies that
are the last chance for some of these species, such as C. rufus and C. simensis, to escape
extinction and to allow other species such as C. lupus to return to a range from which it
had been exterminated.

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cts on File Inc. New York. 1994.
Bekoff, M. and E.M. Gese. 2004. “Coyote.” Canids: Foxes, Wolves, Jackals and Dogs –
2004 Status Survey and Conservation Action Plan. IUCN/SSC Canid Specialist
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Beyer, A., B.T. Kelly and M.K. Phillips. 2004. “Red Wolf.” Canids: Foxes, Wolves,
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