Organisms are classified into a hierarchical classification that groups closely related individuals.
The species is the basic biological unit around which classifications are based.
Iczn(The International Commission on Zoological Nomenclature )Al Nahian Avro
The International Commission on Zoological Nomenclature (ICZN) acts as adviser and arbiter for the zoological community by generating and disseminating information on the correct use of the scientific names of animals. The ICZN is responsible for producing the International Code of Zoological Nomenclature - a set of rules for the naming of animals and the resolution of nomenclatural problems.
Organisms are classified into a hierarchical classification that groups closely related individuals.
The species is the basic biological unit around which classifications are based.
Iczn(The International Commission on Zoological Nomenclature )Al Nahian Avro
The International Commission on Zoological Nomenclature (ICZN) acts as adviser and arbiter for the zoological community by generating and disseminating information on the correct use of the scientific names of animals. The ICZN is responsible for producing the International Code of Zoological Nomenclature - a set of rules for the naming of animals and the resolution of nomenclatural problems.
These slides contain short definitions and history of systematic zoology and taxonomy. The information in slides is taken from 2-3 taxonomy books and lectures from university at master level.
To determine the variation and the limitation between species, many concepts have been proposed.
When a taxonomist study a particular taxa, he/she must adopted a species concept and provide a species limitation to define this taxa.
Plant kingdom as other living kingdoms has a hierarchy structure ends mostly with species rank.
Species are one of the basic units to compare in almost all fields of biology.
A species is defined as the largest group of organisms in which two individuals are capable of reproducing fertile offspring, typically using sexual reproduction.
Definition of a species as a group of interbreeding individuals cannot be easily applied to organisms that reproduce only or mainly asexually.
If two lineages of oak look quite different, but occasionally form hybrids with each other, should we count them as different species?
Idea of a species is something that we humans invented for our own convenience.
‘‘No matter what variations occur in the individuals or the species, if they spring from the seed of one and the same plant, they are accidental variations and not such as distinguish a species permanently; one species never springs from the seed of another nor vice versa” - JOHN RAY.
Used a sexual system ‘‘natural system” for defining species - LINNAEUS.
‘‘A species is a collection of all the individuals which resemble each other more than they resemble anything else, which can by natural fecundation produce fertile individuals, and which reproduce themselves by generation, in such a manner that we may from analogy suppose them all to have sprung from one single individual” - DE CANDOLLE.
Classical and molecular taxonomic parameters, species concept, systematic gradation of animals, nomenclature, modern scheme of animal classification into sub-Kingdom, division, section, phyla and minor phyla
It states that the present day complex plants and animals have evolved from earlier simpler forms of life by gradual changes. SEQUENTIAL EVOLUTION ,DIVERGENT EVOLUTION, Theories of evolution.
These slides contain short definitions and history of systematic zoology and taxonomy. The information in slides is taken from 2-3 taxonomy books and lectures from university at master level.
To determine the variation and the limitation between species, many concepts have been proposed.
When a taxonomist study a particular taxa, he/she must adopted a species concept and provide a species limitation to define this taxa.
Plant kingdom as other living kingdoms has a hierarchy structure ends mostly with species rank.
Species are one of the basic units to compare in almost all fields of biology.
A species is defined as the largest group of organisms in which two individuals are capable of reproducing fertile offspring, typically using sexual reproduction.
Definition of a species as a group of interbreeding individuals cannot be easily applied to organisms that reproduce only or mainly asexually.
If two lineages of oak look quite different, but occasionally form hybrids with each other, should we count them as different species?
Idea of a species is something that we humans invented for our own convenience.
‘‘No matter what variations occur in the individuals or the species, if they spring from the seed of one and the same plant, they are accidental variations and not such as distinguish a species permanently; one species never springs from the seed of another nor vice versa” - JOHN RAY.
Used a sexual system ‘‘natural system” for defining species - LINNAEUS.
‘‘A species is a collection of all the individuals which resemble each other more than they resemble anything else, which can by natural fecundation produce fertile individuals, and which reproduce themselves by generation, in such a manner that we may from analogy suppose them all to have sprung from one single individual” - DE CANDOLLE.
Classical and molecular taxonomic parameters, species concept, systematic gradation of animals, nomenclature, modern scheme of animal classification into sub-Kingdom, division, section, phyla and minor phyla
It states that the present day complex plants and animals have evolved from earlier simpler forms of life by gradual changes. SEQUENTIAL EVOLUTION ,DIVERGENT EVOLUTION, Theories of evolution.
well, dis z again another ppt on molecular biology..
I know dis kinda luks boring bt pretty informative
thanks
let me know wat you think abt dis
don't forget to comment
Evolution is a very complex, irreversible and extremely slow process. the events related to theories of evolution and evidences of evolution are discussed. Theories of origin of life are as follows. 1)Theory of Special creation or devine origin 2) The theory of spontaneous generation/ Abiogenesis 3)Spallanzani experiment 4) Redi Experiment (1680) 5) Pasteurs Experiment (1864) 6) Panspermia 7) Theory of Catastrophism ( G,Cuvier) 8) Naturalistic theory ( Oparin & Haldane, 1920)
This is my attempt to explain punctuated equilibrium vs. phyletic gradualism and how both ideas contribute to the controversy of what constitutes a species.
Hear Duke evolutionary biologist Mohamed Noor discuss the work that made him one of only a dozen scientists honored with the Darwin-Wallace Medal in 2008. This prize is given only once every fifty years to those twelve scientists who have done the most to advance Darwin's thinking.
Although Darwin's book title suggested that he provided us with insights on the origin of species, in fact, he only focused on the process of divergence within species and assumed the same process "eventually" led to something that could be called a new species.
This event was taped live as part of the Periodic Tables: Durham's Science Cafe series at the Broad Street Cafe. Periodic Tables is a Museum of Life and Science program. For more info please visit us at http://www.ncmls.org/periodictables
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
Model Attribute Check Company Auto PropertyCeline George
In Odoo, the multi-company feature allows you to manage multiple companies within a single Odoo database instance. Each company can have its own configurations while still sharing common resources such as products, customers, and suppliers.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
June 3, 2024 Anti-Semitism Letter Sent to MIT President Kornbluth and MIT Cor...Levi Shapiro
Letter from the Congress of the United States regarding Anti-Semitism sent June 3rd to MIT President Sally Kornbluth, MIT Corp Chair, Mark Gorenberg
Dear Dr. Kornbluth and Mr. Gorenberg,
The US House of Representatives is deeply concerned by ongoing and pervasive acts of antisemitic
harassment and intimidation at the Massachusetts Institute of Technology (MIT). Failing to act decisively to ensure a safe learning environment for all students would be a grave dereliction of your responsibilities as President of MIT and Chair of the MIT Corporation.
This Congress will not stand idly by and allow an environment hostile to Jewish students to persist. The House believes that your institution is in violation of Title VI of the Civil Rights Act, and the inability or
unwillingness to rectify this violation through action requires accountability.
Postsecondary education is a unique opportunity for students to learn and have their ideas and beliefs challenged. However, universities receiving hundreds of millions of federal funds annually have denied
students that opportunity and have been hijacked to become venues for the promotion of terrorism, antisemitic harassment and intimidation, unlawful encampments, and in some cases, assaults and riots.
The House of Representatives will not countenance the use of federal funds to indoctrinate students into hateful, antisemitic, anti-American supporters of terrorism. Investigations into campus antisemitism by the Committee on Education and the Workforce and the Committee on Ways and Means have been expanded into a Congress-wide probe across all relevant jurisdictions to address this national crisis. The undersigned Committees will conduct oversight into the use of federal funds at MIT and its learning environment under authorities granted to each Committee.
• The Committee on Education and the Workforce has been investigating your institution since December 7, 2023. The Committee has broad jurisdiction over postsecondary education, including its compliance with Title VI of the Civil Rights Act, campus safety concerns over disruptions to the learning environment, and the awarding of federal student aid under the Higher Education Act.
• The Committee on Oversight and Accountability is investigating the sources of funding and other support flowing to groups espousing pro-Hamas propaganda and engaged in antisemitic harassment and intimidation of students. The Committee on Oversight and Accountability is the principal oversight committee of the US House of Representatives and has broad authority to investigate “any matter” at “any time” under House Rule X.
• The Committee on Ways and Means has been investigating several universities since November 15, 2023, when the Committee held a hearing entitled From Ivory Towers to Dark Corners: Investigating the Nexus Between Antisemitism, Tax-Exempt Universities, and Terror Financing. The Committee followed the hearing with letters to those institutions on January 10, 202
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
2. Quick Write @ end of class
• Normal watermelon plants are diploid (2n = 22),
but breeders have produced tetraploid (4n = 44)
watermelons. If tetraploid plants are hybridized
with their diploid relatives they produce triploid
(3n = 33) seeds. These offspring can produce
triploid seedless watermelons and can be further
propagated by cuttings. Are the diploid and
tetraploid watermelon plants different species?
Explain.
3. CH 22: The Origin of SpeciesCH 22: The Origin of Species
Overarching Question:Overarching Question:
How doesHow does speciationspeciation (the development of a(the development of a
new species) fit into evolutionary theory?new species) fit into evolutionary theory?
4. Biological Species Concept
Decide whether the organisms in each of the following
examples belong to the same species:
Example A Example B Example C
Harris’ antelope squirrel
vs. white-tailed antelope
squirrel
Various breeds of dogs
Donkey, horse, mule
5. The biological species concept =population whose
members have the potential to naturally produce viable
offspring
6. What are some things that might keepWhat are some things that might keep
organisms from breeding successfully??organisms from breeding successfully??
Modes of reproductive isolation (blocking gene flow between
populations)
Achieved through mechanisms that can be classified into two main
categories:
1. Prezygotic barriers- impede mating before fertilization can even
take place
2. Postzygotic barrier- prevent a hybrid zygote from developing into
a viable, fertile adult.
The Grand Canyon separating
land animals-pre/postzygotic?
Pre/postzygotic?
7.
8. Prezygotic BarriersPrezygotic Barriers
Habitat/geographic
isolation: - live in different
places
e.g. Two snakes of the same
genus live in the same area, but
one is aquatic & the other is
terrestrial-they just don’t have
many encounters because they
spend their time in different
places
9. Temporal isolation – timing is different
these skunks live in the same area, but
they are reproductively active during
different seasons
Do a little dance….
Behavioral isolation – mating rituals
different e.g. certain courtship rituals are
performed before mating takes place
Prezygotic BarriersPrezygotic Barriers
10. Prezygotic BarriersPrezygotic Barriers
Mechanical Isolation – parts don’t fit or come
together e.g. physical differences inhibit
cross-fertilization2 flowers of the same
genus have different colors and therefore
attract different pollinators
Gametic Isolation: biochemical mechanisms
may prevent gametes from fusing, or the
reproductive tract in the
female may be an unfavorable
environment for sperm
11.
12. Postzygotic BarriersPostzygotic Barriers
• Reduced hybrid viability- hybrids
do not complete development
Hybrid breakdown- F1s are viable,
but later generations are not
Reduced hybrid fertility- the hybrid
offspring is sterile
13. Quick Think
1. Define REPRODUCTIVE ISOLATION
2. List the 5 pre-zygotic and 3 post-zygotic
barriers to reproduction
14. Quick Think
• 2 species of bird in a forest are not known
to interbreed. One species feeds and mates
in the treetops and the other on the ground.
But in captivity, the 2 species can
interbreed and produce viable, fertile
offspring. What type of reproductive barrier
most likely keeps these species separate?
Explain your reasoning.
15. Limitations of the Biological Species Concept
• You can’t define a species by reproductive
isolation if the organism reproduces
asexually, as is the case in many bacteria
• What if you’re studying 2 extinct
organisms??? How are you going to be
able to tell whether or not they can mate &
produce viable offspring??
Are these the
same
species?
Are these the same species?
16. Other Definitions of SpeciesOther Definitions of Species• Morphological species concept~ a species is defined by body shape,
size, & structure
Pros: can be applied to fossils & asexual organisms
Cons: the criteria are subjective
• Paleontological species concept~ Classifies fossils based solely on
morphological differences.
Pros/cons exist, but this is our only option with extinct species…unless you can
get a DNA sample
• Ecological species concept~ Distinguishes between species based on
their ecological niche-its biological role in the community
Pros: can be used for sexual & asexual organisms bacteria can be classified
based on their food source
Cons: two organisms may have a distinct niche, but still be able to interbreed
successfully
• Phylogenetic species concept~ a species is a set of organisms that
share a unique genetic history. Compares physical characteristics as
well as molecular sequences.
Pros: can distinguish between species that are morphologically similar. Often
times all you need is a DNA sample
Cons: hard to say how genetically different something has to be before it can be
considered a different species
17. The Bottom LineThe Bottom Line
• Species is somewhat of a vague term in that there is no
single system for classifying one group of organisms as
separate from another…although there is an effort to
find one “uniform species concept”
• Researchers are often forced to use a different definition
for “species” based on the circumstances & info they
have
Although the biological species concept is still
heavily used, the advent of DNA technology
reinvented the phylogenetic species concept and
cladistics. In fact, genetic
similarity/dissimilarity is leading to massive
reclassifications. Example= in plants, the
classification as a dicot is being phased out
18. Modes of SpeciationModes of Speciation
• Allopatric Speciation VS Sympatric SpeciationAllopatric Speciation VS Sympatric Speciation
Allopatricpart of the
population is
geographically isolated
from the rest of the
population & forms a
new species since it is
reproductively isolated
Sympatric speciation
occurs while the
organisms are still
cohabiting.
19. Allopatric SpeciationAllopatric Speciation
• Example of geographic barriers: Mountain
ranges, rivers, land bridges (the Isthmus of
Panama), a big lake becoming a bunch of
smaller lakes, the Grand Canyon...
20. Allopatric SpeciationAllopatric Speciation
• An example of Allopatric Speciation in the Grand
Canyon: Antelope Squirrels. The separated gene
pools diverge via mutations, natural selection, sexual
selection, genetic drift, etc.
22. Sympatric SpeciationSympatric Speciation
• “Barriers” in sympatric speciation include
chromosomal changes, habitat differentiation, &
sexual selection.
– Polyploidy:
Tetraploids can only produce viable
offspring with themselves (self-
pollination) or other tetraploids=
reproductive isolation
23. Sympatric SpeciationSympatric Speciation
• “Barriers” in sympatric speciation include chromosomal changes,
habitat differentiation, & sexual selection.
– Habitat Differentiation:
In soapberry bugs, beak
length dictates which fruit
on a plant the insects eat.
Even though the 2 species
live on the same plant, they
don’t run into each other
often since they have different
food preferences = decreased
gene flow.
24. Sympatric SpeciationSympatric Speciation
• “Barriers” in sympatric speciation include chromosomal changes,
habitat differentiation, & sexual selection.
– Sexual Selection: Cichlids in Lake Victoria. These 2
similar species vary in color. Females of the 2 species
preferentially mate with males who have
the same
coloration
that they
do.
25. Quick Think
• How are sympatric and allopatric speciation
similar and how are they different?
26. Quick Think
• Explain why allopatric speciation would be
less likely to occur on an island close to the
mainland than on a more isolated island of
the same size.
27. The Tempo of Speciation: How Fast Does All
This Happen?
• A couple of suggestions: Gradualism VS
Punctuated Equilibrium
Gradualism: species P.E.: new species
diverge slowly over emerge suddenly
time then stabilize for a
while before
another divergence
What type of
speciation do you
think we might see
with the finches on
the Galapagos?
How is speciation
of this type related
to the environment?
28. Adaptive RadiationAdaptive Radiation
• Diversely adapted species stemming from a common
ancestor
– Often occurs when a founder population settles in a new
environment, or when extinction opens up an ecological
niche.
– These species
of silver sword share
a common ancestor,
but have diverged
after colonizing
different
Hawaiian islands
29. Macroevolutionary Changes Can Accumulate
Through Many Speciation Events
• Evolutionary
Novelty: in most
cases, complex
structures
evolved in
increments from
simpler
prototypes in
other species
30.
31. •Exaption: An existing structure that is
co-opted after having previously served
a different function. Ex: feathers may
have been favored
by sexual selection
before being used
to assist in flight
32. Evolution of the Genes That Control DevelopmentEvolution of the Genes That Control Development
• Heterochrony-evolutionary change in the rate/timing of
developmental events; this can result in a change in the
overall appearance of a species. A chimp’s
jawbone elongates at a faster
rate relative to the rest of its
skull, thus giving it its
characteristic shape. Note that
early in development, the
human &chimp skull look similar.
33. Evolution of the Genes That Control DevelopmentEvolution of the Genes That Control Development
• Paedomorphosis: Sexual maturity is accelerated
– Ex: most salamander species undergo metamorphosis
before sexual maturity. A relatively small genetic
change accelerates sexual development to the point
where this salamander is an adult
even though it still has
larval features such as gills
34. Changes in Spatial PatternChanges in Spatial Pattern
• Recall: Homeotic Genes determine where limbs
grow on the general body plans of organisms
– HOX genes are specific homeotic genes in animal
embryos
– Here, turning on additional
HOX genes allows the buds
to give rise to digits in
chickens Determine the
fate of whole
groups of cells
35. A “Rough Sketch” of the EvolutionA “Rough Sketch” of the Evolution
of Vertebrates from Invertebratesof Vertebrates from Invertebrates
• Alterations are
associated with HOX
genes as well
Most inverts only have one cluster
of Hox genes
A duplication mutation could have
led to the evolution of the first verts.
A duplication mutation or a
nondisjunction mutation may have
given rise to the 4 sets of Hox genes
seen in verts today
36. Remember, Evolution is NOT GoalRemember, Evolution is NOT Goal
OrientedOriented
• Species are not trying to become better…
37. Check for Understanding
1. Two species of birds in a forest are not
known to interbreed. One species feeds
and mates in the treetops and the other on
the ground. But in captivity, the two
species can interbreed and produce viable,
fertile offspring. What type of
reproductive barrier most likely keeps
these species separate?
38. Check for Understanding
• Normal watermelon plants are diploid (2n = 22),
but breeders have produced tetraploid (4n = 44)
watermelons. If tetraploid plants are hybridized
with their diploid relatives they produce triploid
(3n = 33) seeds. These offspring can produce
triploid seedless watermelons and can be further
propagated by cuttings. Are the diploid and
tetraploid watermelon plants different species?
Explain.
39. Quick Write
• How can the Darwinian concept of descent
with modification explain the evolution of
such complex structures as the vertebrate
eye or heart?