1. Evolution concepts

2. Phyletic evolution (anagenesis): Yes, but not this example!
Implications

3. Contrast of two ideas about the fundamental basis of change
Lamark: principles of 1) use and disuse 2) inheritance of acquired characteristics
Darwin: principle of
evolution by
natural selection
Variation present
before it would be
of value.

4. Transformational
evolution
Lamarck
Variational
evolution
Darwin

5. 1798

7. Example of an
adaptation.
Giraffe neck size
Why do giraffes have
Long necks?
Set up an hypothesis.

8. Evidence

11. Why do giraffes have long necks?
There was (is) a difference in neck size among bulls.
Competition for females during a brief reproduction season. Males engage in combat; necks are used.
Neck length accompanied by a gain in mass
Sexual selection: males with stronger necks have greater mating success….win more contests.
Alleles resulting in stronger necks tend to be passed on to progeny and increase in the population.
The population changes over time.

12. Biological diversity: created or product of evolution
A random survey of 2,000 adults
42% believed that biological diversity has not increased since the beginning of time.
Special creation
48% believed that biological evolution has taken place.
Descent with modification

13. Special creation The intelligent design argument
1. Fixity of species
2. Each species was independently created
No relationships among species
3. Biblical evidence: origins are recent
Movement called creation science attempts to legitimize special creation.
Creation “science” is not a science.
Argument is based on idea of Intelligent Design supported by the idea of irreducible complexity.

14. Bacterial flagellum: irreducible complexity?
E. coli
Mobility
Yersinia
Type III Export System
30 protein components
20 proteins involved in assembly

15. Eyes of mollusks: snails, clams, squid & octopi

16. Convergent evolution
Evolution-2e-Fig jpg