Evolution Flashcards
(8 cards)
What is evolution
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An ongoing process of genetic changes in a population
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Gives rise to new species
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Driven by natural selection
and adaptation
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Implies that all life has a common ancestor
Who is the father of the theory of evolution?
Charles Darwin
(1809-1882) –Father of the Theory of Evolution
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Theory of evolution sometimes called “Darwinism”
Where was Darwin from?
What did he do?
What are Darwin’s Finches?
Turtles?
England
Travelled for 5 years, collected and observed things
loved south America and Galapagos
Adaptation
Finches lived on a different island and he looked at how they adapted to get their food
Long beak to get seeds inside flower
Insect eater- short beak
2 turtles, 2 islands
1- sturdy shell, heavy- short legs- lots of vegetation- doesn’t have to walk far, food is easy
2 Shell is lighter and longer legs and longer neck as it had to forage for food
Biological evidence that points to a common ancestor
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Anatomical similarities between organisms
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Useless (vestigial) traits in modern species
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Shared embryonic developmental pathways
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Fossil evidence
Anatomical similarities between organisms
bones
Mammalian forelimbs have the same set of bones
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Underlying structure is similar despite the different functions
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Suggests common ancestry
Bat- elongated for flight
Sea lion
Lion-
Chimpanzee
Human
Useless (vestigial) traits in modern species
Vestigial organs in animals are
internal organs that serve no useful function
Ø Served a function in an ancestor population
Examples:
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Appendix
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Legs in some snake- remanence
Shared embryonic developmental pathways
(4 of the 5 5 distinctive features of Chordates)
Dorsal Tubular nerve chord
Notochord- tissue on dorsal side of body- flexible rod located between digestive tract and nerve chord
Pharyngeal gill slits
post Anal tail (tail bone)
- all visible in early embryo
Fossil evidence
Much better record of shell organisms (mollusks and clams) rather than other organisms
because of exoskeleton
