Synapomorphy
change in character, all descendants have it
symplesiomorphy
some descendants have lost
Convergence
similar characteristics derived independently
autapomorphy
synapomorphy but just in one species, new characteristic, doesn't really tell us anything about relationships
which provides direct evidence for classification of species into higher taxa?
synapomorphy
Ex. of convergence
3 times where mammals have become aquatic cetaceans:
whales + dolphins
manatees + dugongs
seals + sea lions
Dollo parsimony - how is this concept related to weighted parsimony and what type of characters is it best applied to?
extreme version of not trating all mutations the same, some are more likely to stay
complex
once a trait is lost it is never revolved
Ex. stick insects of wings lost in ancestor but revolved, means that genes don't go away but gene pathway can be turned back on and utilized
weighted parsimony
not all evolutionary changes are equal
at the level of DNA, maybe don't trat every mutation equally, give more likelihood to one mutation than another, and known from previous data
based of frequencies and models of evolution
Maximum likelihood says theres a percent chance
1. branch lenghts play a role
2. and probabilities
Allelic variant (?)
between species
Does impact of mutation matter?
No its all data, still evidence of similarities
How does mapping character traits onto a phylogeny allow us to reconstruct ancestral states?
once we map a trait on a phylogeny, allows us to see variation
how is inference of ancestral sates different under a maximum likelihood assumption?
take into account branch lengths and models of evolution, what types of mutations are more likely