BIOL 351 Lecture Notes - Lecture 2: Magnificent Tree Frog, African Clawed Frog, Phenotypic Plasticity
Document Summary
We almost never have sequence info from ancestors. Close relative of ingroup, but not as close as members in the actual ingroup. Hypothesis a or b in slides (the way you can write where the differences lie within a phylogeny. Labile halts: evolved repeatedly transition easily (adapt to environment) conserved transition slowly. Sources of homoplasy (looked like some ancestor but isn"t) Convergent evolution: independent appearance in different lineages of similar derived traits when using phenotypes, this is important because phenotypes evolve. Evolutionary reversals: loss of a derived trait, returning lineage to ancestral condition. Both cause conflicting patterns in putative synapto and synplesomorphic traits. Convergent: african clawed frog and magnificent tree frog both produce toxin caerulein the toxin is 10 aa long. Cc-cc1 produce what is supposed to be produced. Gg-gg1 produce what is supposed to be produced. Invariant-uniformative we get rid of those sequences in phylogenic tree because all are different genes.
