Website: http://evolution.berkeley.edu/
Explain how each of the following provides evidence that evolution occurs: the fossil record, biogeography, comparative anatomy, comparative embryology, and molecular biology.
Explain how analyzing sedimentary rock layers and radiometric dating help us understand the fossil history of life on Earth.
Explain how the formation and break up of the supercontinent Pangaea affected the evolution of life on Earth.
Describe the common misconceptions about evolution and explain why they are incorrect
One of the strengths of a theory is that it can be tested using independent lines of evidence
Historical record of Ancient life

fossils
Historical evidence present in modern life

Biogeography: distribution of species

Comparative anatomy: body structures of species

Comparative embryology: body structures during development
 Molecular biology: composition of genetic material or products
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 remains of organisms or signs of organisms preserved over time
 Shows different life forms and also clues to the way they lived
 Two methods are used to determine the age of fossils
Relative dating places fossils in a time sequence by noting their positions in layers of rocks
2

Numerical dating relies on the decay of radioactive elements, such as Uranium and Carbon giving an exact time
Fossil record supports descent with modification
If one species descended from another:
Fossils should show an ordered pattern
(through time one form is replaced by similar but different forms)
EVIDENCE
 Fossil record shows that
organisms have appeared in
an ordered and consistent sequence
 Fossils that show the intermediate states between an ancestral form and that of its descendants,
are called transitional forms
example: Tiktaalik
3

Do gaps on the fossil record disprove evolution?
Fossils link ancestral species to those living today and also link two species living today
Today’s species do not look very similar, but as we go lower in the fossil layers
the differences disappear
4

Geographical distribution of organisms on the earth supports descent with modification
If one species descended from another: there should be some geographic continuity from where the ancestor species and the descendent species are found
Marsupial mammals are found in the Americas as well as Australia
They are not found swimming across the Pacific Ocean, nor have they been discovered wandering the Asia.
How could marsupials have gotten from one place to a location half a world away?
5

Continents have been and are constantly on the move
Caused by
Constant slow movement of plates of earth’s crust on the underlying molten mantel
Continental drift animation
Continental drift shows that continents came together 250 mya and drifted apart 180 mya
Marsupials rode the continents to their present positions
6

If one species descended from another we expect that similar species should have similar DNA or similar proteins
Since embryo development is coded in the DNA
(inherited and changeable)
Related species will have similar embryo development
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