BIO 141: Evidence for Evolution ( 1 & 2)

what were the common beliefs in Darwin and Wallace time

the earth was young ( created 4004 BC)

species were created by God

species were perfect

species were fixed and did not vary

species did not change

darwin's theories

evolutions as such (species change)

common descent

multiplication of species

gradualism

natural selection (incl. sexual selection)

Descent with Modification

the gradual diversifying evolution of new species from common ancestors through a process of natural selection

plato

typological thinking: species fixed and did not change, also know as special creation or intelligent design

Aristole

typological thinking + scale of nature

lower organisms- higher organisms different levels of functionality

Lamarck

organisms originate through spontaneous generation; then evolve into higher organisms over time

ex; very low organisms age their time on earth increases then that species can become more complex

Darwin/ Wallace

Organisms have common ancestors and diversify over time

ex; no higher or lower rank, all species evolve over time

how old is the earth, apply this concept to geology we have a really old earth

4.5 billions old

Uniformitarianism

geological forces operated at the same rate in the past as they do now, implication the earth is extremely old

Case Study: South American birds

two species of flightless birds; different from flightless birds elsewhere, yet similar many respects

the common rhea (rhea americana)

relative- regular size ostrich

the lesser rhea (rhea darwinii)

relative- size of a chicken

similar species are found in the the same geographic area

exemplified by Galapagos mockingbirds: different species, yet similar to each other and a main land species

darwin's model evolution of the mockingbird

eastern islands, southern islands, central islands, and western islands,

ex; originally all the birds were on the eastern island then they migrated to south then central then to west

T or F: were the islands close together

true

law of succession

correspondence between fossils and living forms within a location; as is predicted by descent with modification

artifical breeding

evidence for descent with modication through artifical selection

T or F pigeons were a way to show wealth in london

true

intermediate forms

gradual stages between simple and complex structures

evidence in nature, slow development of complex structures

example of intermediate forms

the human eye

intermediate forms in eye evolution ( octopus) stage 1

pigmented cells, epithelial cell, nerve fibers

stage 2 of octopus eye nerve fibers,

tells where the sun/light is coming from

stage 3 water filled cavity

- now slowly able to focus on the image

stage 4 lens

allows for refraction; makes the image more crisp

t or f humans do not have a blind spot

false

t or f octopus eyes are better then humans

true, but why (answer chinotu)

what were transitional fossils used to be called and why is incorrect

missing links, the fossils are not direct descents of previous organisms or direct ancestors of later organisms

disclaimer: does not mean that species with intermediate form, did not give rise to present day species today

t or f transitional fossils are essentially intermediate forms in the fossil record

true

example of transition fossil

dinosaurs to birds (archaeopteryx)

t or f species fossilize better in the water

true

t or f whales are not mammals

false

1. pakicetids 52 mya

full pelvis/femur adapted for land

2. ambulocetids 50 mya

full pelvis/femur adapted for swimming

3. remingtonocetids

no change

4. protocetids 49-37 mya

full pelvis/femur adapted more adapted for swimming

5. Basilosaurids 38 mya

tiny pelvus/ femur

contemporary whales

vestigial pelvis/ femur (Floating)

pakicetids ear structure

had inner structure of an land animal

ambulocedtids ear structure

isotope of his bone structure, size a cow/deer also has a hind limb

t or f evolution of whale's ear, more aquatic structure to handle water pressure

true