1. Evidence
for
Evolution

2. The Fossil Record

3. Why is the
giraffe's neck
so long?

5. Adaptation
The evolution of a structure, behavior, or internal process that enables an organism to respond to stimuli and better survive in an environment. A trait that gives an organism an advantage in the struggle for survival.
Adaptation in species develop over many generations and can be physiological or structural.

6. Can a human tell the difference between three types of candies?
Mimicry Lab
Can a human tell the difference between three types of candies?
Milk chocolate M&M – mmmmmmmm yummy good!
Skittles – tasty but will make you sick every time
Dark chocolate M&M – you DIE!!

9. Organisms have ___2___ of many traits and sometimes the environment can ___1___one ___2___over another. Other times a __1__can occur and a ___2___will appear that gives an organism ___3___in the environment. Those with the ___1__have a __1___and often live long and___2___. These organisms have a high level of ___3___ in the environment in which they live. As these organisms continue to______1____, passing on the __1___for the__2___, the frequency of those___3___ increases so that over time the species will__2___. This process is known as_____3____. A species ___3__ to its environment can take___1___. This is known as___1___. __3___evolve___2___ adapt. 1
Evolution
favored trait
genetic mutation
alleles
favor
reproduce
survival advantage
thousands or millions of years 2
natural variation
change
variation
favored trait
produce more offspring
new trait
organisms 3
Species
an advantage
natural selection
fitness
alleles
adapting

10. Types of Natural Selection
Types of selection

13. What type of selection did our bunnies have?

14. The Origin of Species

15. Speciation can occur…
Punctuated Equilibrium
Gradualism

16. NO YES Can They Reproduce?
Western Meadowlark
Eastern Meadowlark
The biological species concept is based on inter-fertility, rather than physical similarity.
YES

17. SPECIATION How are they isolated?
A species is defined as being reproductively isolated from other species.
How are they isolated?
A reproductive barrior is anything that provides a barrier to natural reproduction – can either be in the actual processes of mating or in habitat

18. Geographic Speciation
Geographic barriers can start the process of speciation

19. Allopatric Speciation
Ammospermophilus leucurus
Ammospermophilus harisi
Geographic separation of populations restricts mating. Each group is exposed to different environmental pressures and adapts accordingly until the two can no longer reproduce with each other and two species arise

20. populations living next to each other become distinct species.
Parapatric Speciation
populations living next to each other become distinct species.
Two species of garter snakes live in the same area but because one lives mainly in water and the other is primarily terrestrial they rarely encounter each other.

21. Sympatric Speciation Gamete Isolation –
The gametes do not form a zygote
Chromosomal changes due to mutations
More common in plants

22. The Mechanics –
attempts to reproduce may be made but because anatomy is incompatible reproduction can’t occur

23. Temporal Isolation Western Spotted skunk & Eastern
Share a habitat but mate at different times of the year
Western = summer
Eastern = winter

24. Courtship What lights your fire?
Many species have elaborate rituals for attracting a mate – what works for one species doesn’t necessarily work for others

25. Types of natural selection
can lead to speciation
Types of speciation
can lead to different
kinds of Evolution

26. Divergent Evolution
Species that were once similar to an ancestral species become increasingly distinct adapting to different environmental conditions

27. Convergent Evolution
Unrelated species occupy similar environments in different parts of the world. Develop similar characteristics due to similar environmental pressures.

28. MASS EXTINCTION
It’s all over!!