BIOA01H3 Lecture Notes - Lecture 7: Atavism, Convergent Evolution, Molecular Clock

• School: UTSC
• Department: Biological Sciences
• Course: BIOA01H3
• Professor: Monica Sauer

Document Summary

Slide 9: 1) convergent evolution: similar selection pressure can lead to similar traits: evolutionary reversal: traits reverts from derived to ancestral state. Common with gene sequence data, reversion is very common because of only four base. Genes can be turn on/off at evolutionary time. Development network control the gene if its turn on or off, so that it"s not express. Then after in future evolutionary time another development network can turn it on again. Slide 10: the frog still had the genes to make teeth. Big difference on how structure is built and support. Use a large number of traits to infer phylogenetic patterns. Most phylogenies are based on large dataset with many characters. Slide 12: principle of parsimony: the simplest it the best. Among competing hypotheses, the one with the fewest assumptions should be selected. Any particular evolution change is a rare event, fewest assumption about evolutionary changes. Assume that the same change happening twice is unlikely.