Evolution, Ecology & Biodiversity

This course covers:

- Population Genetics- Evolution- Diversity of life- Ecology

- major theme of the course is evolution

What do you think is the best definition of evolution (for a biologist)?:

a) Origination of species by developmentfrom earlier forms

b) Change in allele frequencies in a populationover generations

c) Descent with modificationd) The survival of the fitteste) Gradual process in which something changes

into a more complex or better form

Population Genetics necessary to understand evolution

Evolution is relevant to understanding virtually everything about living things!

Why are there millions of species on this planet? What are they?What can we learn from this diversity?

How do these species interact with each other & their environment?

Evolutionary thinking

Evolutionary biology credited to Darwin (1859)- not first to think of evolution…

Georges-Louis Leclerc (Comte de Buffon) - 1707-1788- believed in long history of earth, change in organisms, noted vestigial organs

Erasmus Darwin - 1731-1802

- believed that life had evolved from simple origins- wrote poetry…

Organic life beneath the shoreless wavesWas born and nurs'd in ocean's pearly caves;First forms minute, unseen by spheric glass,Move on the mud, or pierce the watery mass;These, as successive generations bloom,New powers acquire and larger limbs assume;Whence countless groups of vegetation spring,And breathing realms of fin and feet and wing.

- Etienne Geoffroy Saint Hilaire (1772-1844)- variations on single body plan, homologies

The best known ‘pre-Darwinian’ evolutionistwas….?

His theory made what well-known argument?:a) the environment directly modifies organismsb) individuals with greater fitness would pass

on their traitsc) changes in a trait arise by chanced) traits improved by frequent use would be

passed on to offspringe) many past species went extinct

Jean Baptiste de Lamarck (1744-1829)

- best known evolutionist pre-Darwin- believed species change AND suggested mechanisms

by which it might happen

- tendency to increase in size- perception of needs- use and disuse, inheritance of

acquired characters

Charles Darwin - the man…

- first to accumulate sufficient evidence to convince people that evolution had occurred

- first to develop a logical, coherent mechanism to explain how & why evolution happens

- keen naturalist, traveled around world on The Beagle (1832-36)

Where in the world are armadillos found?

a) Americas onlyb) Americas and Africac) Americas and Asiad) Americas & Australiae) World-wide

- fossils in South America, birds in Galapagos islands, etc. led him to question species fixity

Glyptodon Large Hairy Armadillo

4 spp. ofmockingbirdsfrom Galapagos