1. The Origins of New Species

2. What is a species? Biological Species Concept:
A population or groups of populations whose members have the ability to breed with one another in nature and produce fertile offspring
Members of one species cannot successfully breed with members of another species
Excluding individuals who reproduce asexually
A jaglion or jaguon is the offspring
between a male jaguar and a female
lion (lioness).

3. A species is organisms who have the ability to breed with one another in nature and produce fertile offspring (not including those organisms who breed asexually)

4. Micro- to Macroevolution
Micro- is a change in the allele frequencies within a population
Macro- are the biological changes that include the
Origin of different species
Extinction of species
Evolution of major new features of living things
Speciation: origin of new species
Main focus for macroevolution because it leads to biological diversity

5. A species is organisms who have the ability to breed with one another in nature and produce fertile offspring (not including those organisms who breed asexually)
Microevolution is a change in the allele frequencies within a population and can lead to…see below
Macroevolution are the biological changes that include the:
- Origin of different species
- Extinction of species
- Evolution of major new features of living things
Speciation is the origin of new species

6. Reproductive Barriers Between Species
Reproductive isolation
Some kind of reproductive barrier which keeps two species from interbreeding
Usually a result of two or more of the following barriers:
Timing
Behavior
Habitat
Others

7. Reproductive Barriers Between Species
Examples:
Timing
Different breeding seasons
Behavior
Different courtship or mating behaviors
Habitat
Adapted to different habitats in the same general location
Others
Reproductive structures are physically incompatible
Gametes may only be transferred among the single species
Infertile offspring as a result of a hybrid fertilization

8. Macroevolution are the biological changes that include the:
A species is organisms who have the ability to breed with one another in nature and produce fertile offspring (not including those organisms who breed asexually)
Microevolution is a change in the allele frequencies within a population and can lead to…see below
Macroevolution are the biological changes that include the:
- Origin of different species
- Extinction of species
- Evolution of major new features of living things
Speciation is the origin of new species How is a new species created? Reproductive Isolation: Some kind of reproductive barrier which keeps two species from interbreeding, like: - timing: different breeding seasons - behavior: different courtship or mating behaviors habitat: adapted to different habitats in the same general location others: incompatible reproductive structures or gametes, production of infertile/sterile offspring
Salmon cuttlefish hehe birds frogs stickleback

9. Geographic Isolation and Speciation
Separation of populations as a result of geographic change or dispersal to geographically isolated places
Geographically isolating species can lead to speciation
Mountain ranges, rivers, lakes, glaciers, etc can spilt populations of organisms that cannot cross the barrier
If members of a population disperse and separate themselves to an isolated location can lead to speciation through geographic isolation

10. Geographic Isolation and Speciation
Not all species are separated by the same barriers
Wind can carry plants’ pollen and seeds across canyons and rivers
Small rodents and other mammals usually don’t dare cross such barriers
Speciation can result from “splinter” populations following their own evolutionary courses
Genetic drift and changes in allele frequencies leading to microevolution play key roles in speciation

11. Geographic Isolation and Speciation
Isolating populations through geographic barriers does not always lead to speciation
Some species may not need to adapt to their new environments and remain the same, still able to reproduce with the original species
Some species adaptations do not lead to a new species and are still able to reproduce fertile offspring when they encounter the original species
Some adaptations do lead to new species
These species are not able to reproduce with the old species
In this model, arrows symbolize
populations that become
geographically separated, then
come together again at a later time.

12. A species is organisms who have the ability to breed with one another in nature and produce fertile offspring (not including those organisms who breed asexually)
Microevolution is a change in the allele frequencies within a population and can lead to…see below
How is a new species created? Geographic Isolation: Separation of populations as a result of geographic change or dispersal to geographically isolated places, like: - Mnt. ranges, rivers, lakes, glaciers, etc can spilt populations of organisms that cannot cross the barrier; EX: birds, pollen can cross rivers and canyons speciation, small mammals usually can’t
Macroevolution are the biological changes that include the:
- Origin of different species
- Extinction of species
- Evolution of major new features of living things
Speciation is the origin of new species How is a new species created? Reproductive Isolation: Some kind of reproductive barrier which keeps two species from interbreeding, like: - timing: different breeding seasons - behavior: different courtship or mating behaviors habitat: adapted to different habitats in the same general location others: incompatible reproductive structures or gametes, production of infertile/sterile offspring

13. Adaptive Radiation
Islands are a great way to study speciation because of the isolation between species
Islands often create unique habitats and conditions that favor one species over another
Adaptive Radiation
Evolution from a common ancestor that results in diverse species adapted to different environments
Process of adaptive radiation
The small population that colonizes the island may go through evolutionary change
Some of these organisms may go to other islands
The process repeats
New species may adapt through genetic drift and adaptations to the different habitats

14. A species is organisms who have the ability to breed with one another in nature and produce fertile offspring (not including those organisms who breed asexually)
Microevolution is a change in the allele frequencies within a population and can lead to…see below
How is a new species created? Geographic Isolation: Separation of populations as a result of geographic change or dispersal to geographically isolated places, like: - Mnt. ranges, rivers, lakes, glaciers, etc can spilt populations of organisms that cannot cross the barrier; EX: birds, pollen can cross rivers and canyons speciation, small mammals usually can’t
Macroevolution are the biological changes that include the:
- Origin of different species
- Extinction of species
- Evolution of major new features of living things
Speciation is the origin of new species How is a new species created? Reproductive Isolation: Some kind of reproductive barrier which keeps two species from interbreeding, like: - timing: different breeding seasons - behavior: different courtship or mating behaviors habitat: adapted to different habitats in the same general location others: incompatible reproductive structures or gametes, production of infertile/sterile offspring
How is a new species created? Adaptive Radiation: Evolution from a common ancestor that results in diverse species adapted to different environments - easy to see on island communities

15. The Tempo of Speciation
Darwin and the theory of natural selection set forth the model of gradual adaptation
Successful species last about 1 to 5 million years
Most of a species unique adaptations occur in the first 50,000 years (1/100th of the lifetime of a typical species)
The adaptations follow the theory of natural selection
Leading speciation to occur in a few hundred to a thousand generations
The theory of gradual adaptation has been replaced with the theory of punctuated equilibrium

16. The Tempo of Speciation
Species often arrive abruptly as evidenced through the fossil record
Some new fossil species appear “suddenly” in a layer of rock and remain for thousands and millions of years without change and then disappear as suddenly as they appeared
Punctuated equilibrium
This model of evolution suggests that species often diverge in spurts of relatively rapid change and the new species may remain mostly unchanged
Long periods of little change (equilibrium) are broken (punctuated) by shorter periods of speciation

17. Macroevolution are the biological changes that include the:
A species is organisms who have the ability to breed with one another in nature and produce fertile offspring (not including those organisms who breed asexually)
Microevolution is a change in the allele frequencies within a population and can lead to…see below
How is a new species created? Geographic Isolation: Separation of populations as a result of geographic change or dispersal to geographically isolated places, like: - Mnt. ranges, rivers, lakes, glaciers, etc can spilt populations of organisms that cannot cross the barrier; EX: birds, pollen can cross rivers and canyons speciation, small mammals usually can’t
Macroevolution are the biological changes that include the:
- Origin of different species
- Extinction of species
- Evolution of major new features of living things
Speciation is the origin of new species How is a new species created? Reproductive Isolation: Some kind of reproductive barrier which keeps two species from interbreeding, like: - timing: different breeding seasons - behavior: different courtship or mating behaviors habitat: adapted to different habitats in the same general location others: incompatible reproductive structures or gametes, production of infertile/sterile offspring
How is a new species created? Adaptive Radiation: Evolution from a common ancestor that results in diverse species adapted to different environments - easy to see on island communities
Tempo of Speciation: Originally thought: gradual adaptation: speciation to occur in a few hundred to a thousand generations Know now: punctuated equilibrium: species often diverge in spurts of relatively rapid change and the new species may remain mostly unchanged

18. ______________________ are the biological changes that include the:
A _____________ is organisms who have the ability to breed with one another in nature and produce __________ offspring (not including those organisms who breed asexually)
____________________ is a change in the allele frequencies within a population and can lead to…see below
How is a new species created? _________________ Isolation: Separation of populations as a result of geographic change or dispersal to geographically isolated places, like: - Mnt. ranges, rivers, lakes, glaciers, etc can spilt populations of organisms that cannot cross the barrier; EX: birds, pollen can cross rivers and canyons speciation, small mammals usually can’t
______________________ are the biological changes that include the:
- Origin of different _____________
- ________________ of species
- Evolution of major new ______________ of living things
____________ is the origin of new species How is a new species created? ___________________ Isolation: Some kind of reproductive barrier which keeps two species from interbreeding, like: - ___________: different breeding seasons - ___________: different courtship or mating behaviors ___________: adapted to different habitats in the same general location ____________: incompatible reproductive structures or gametes, production of infertile/sterile offspring
How is a new species created? _____________________: Evolution from a common ancestor that results in diverse species adapted to different environments - easy to see on island communities
Tempo of Speciation: Originally thought: _______________________: speciation to occur in a few hundred to a thousand generations Know now: ___________ __________________: species often diverge in spurts of relatively rapid change and the new species may remain mostly unchanged