What are the 4 main sources of scientific evidence that support the theory of evolution?
- Comparative anatomy
- Modern molecular biology
- Fossils
- Embryology
What are 2 examples of comparative anatomy? And what are they?
a) Homologous structures: similar body parts in diff. species -> show common evolutionary ancestor. => similar internal anatomy -> + homo. struct. = + closely related
b) Vestigial structures: a body structure that has no purpose but is homologous to functional structures in other organisms. -> shows remains of a structure that is no longer evolutionary advantageous to the organism.
ex for b) : appendix, tailbone
What is analogous structures and can it be used to show evolution? If not, why?
Body structures of diff. species that appear to be similar on the outside + have the same function but doesn’t come from a common evolutionary ancestor.
-> not internally similar
result from convergent evolution, structures evolve to look similar bc of environmental requirement not bc of evolutionnary relatedness.
How can molecular biology be used to estimate how evolutionary related two species are?
Comparing molecular similarities ex: nucleotides in DNA
-> molecular clock: + changes in nucleotide sequence of a gene, the longer they have shared a common ancestor
What is a fossil and how can it can be used to determine evolution?
Its the remains of a dead organism (normally preserved in rock)
Compare a species’ older fossils to newer ones
To estimate how old it is:
1. The sediment layer that it was found in
2. Dating using radioisotopes (ex: C14)
How can embryology give evidence of a common ancestor?
similarities in embryo developpement
