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evolution

a change of species over time

4.5 billion years

beginning of earth

Charles Darwin

is considered the father of modern evolutionary theory and conducted much research in the Galpagos

2 major ideas of Darwins book

Species change over time
changes in a species occur due to natural selection

Natural Selection

some organisms are more suited to their environment and have traits that help them survive and reproduce better than organisms without those traits

Name 5 things that give evidence of evolution

Fossil records, homologous and vestigial structures, comparative embryology and similarities and differences in DNA and proteins

Ways the age of fossils can be determined

by examining how deeply they are buried and the organisms around them and by using radioactive minerals

an example of vestigial structures

hind limbs of whales

an example of homologous structures

forelimbs of vertebrates (alligator, penguin, bat and human)

homologous structures

similar structures in organisms suggest that those organisms had a common ancestor

vestigial

structures that were once useful to an organism no longer serve a purpose - human appendix

embryological development

most vertebrate embryos look alike in the early stages of development and are similar to other organisms ( human embryos have gill pouch, coat of fine fur, short tail for a short time)

DNA and Protein Evidence

many organisms share some of the same DNA with organisms they are related to like the chimpanzee and humans and also a mouse

directional, disruptive and stabilizing selection

three patterns of natural selection

directional selection

one extreme is better suited tot he environment than others like peppered moth in England

Disruptive selection

both extremes are better suited to the environment than the average: Large and small beaks are best for getting food - not medium sized beaks.

stabilizing selection

the average is best suited tot he environment

Causes of evolution other than natural selection

changes in genes due to chance and reproductive isolation

convergent evolution

organisms without a common ancestor begin to look alike due to similar environmental pressures (sharks, penguins and dolphins has similar bodies

coevolution

two organisms evolve in response to changes in each other

punctuated equilibrium

evolution that occurs in jumps or bursts and pauses

Thomas Malthus

wrote that populations tend to grow as much as the environment tends to allow them and sustain them

Gradualism

a process of evolution in which speciation occurs slowly and gradually.

Similarities of structures

provide evidence that all vertebrates share a common ancestor

Reproductive isolation

keeps newly forming species from breeding with each other

Lyell's Principles of Geology

past events must be able to be explained in terms of processes that can be observed

Jean Baptiste Lamark

believed that physical features increase in size because of use or reduce in size because of disuse (incorrect)

Lamark's main idea that Darwin liked

species change according to their environment

Malthus

reasoned that if the human population continued to grow unchecked, sooner or later there would be insufficient space or food

Maltus main idea that Darwin liked

plants and animals - more than humans - could product more offspring than space or food

example of reproductive isolation

kaibab squirrel and abert squirrel

example of co evolution

moth with long tongue and flower with long neck for nectar

Antibiotic resistant bacteria

an example natural selection or evolution and bacteria. New bacteria cannot be killed by old antibiotics

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