Phylogenetics
Describe
the basic problem of fitting nature into a classification system
differences among species arise from the fact
that they undergo evolutionary changes that can differ in intensity and
sequence.
difficult to devise a completely objective
method which fulfills both criteria for a good classification system:
1.
accurate
representation of evolutionary relationships (stores information)
2.
major
features of each group easily described (information is easily retrieved)
Know
that modern phylogenies emphasize accurate representations of evolutionary
relationships at a cost of creating difficult to describe groups.
Define:
cladistics, cladogram, synapomorphy, homoplasy
Know
that the most parsimonious cladograms are the ones that minimize homoplasy
Convergence and reversal should be
relatively rare
Know
that computing power has standardized phylogenetic analysis and that the
classification of many groups of organisms is being re-examined with these new
methods
Describe
when a phenetic classification system may be more useful than a phylogenetic
system