Phylogeny

Phylogeny

volutionary history & relationship of a species or a group of related species

Phylogenetic trees

represent hypotheses based on Morphological similarities & DNA/amino acid/protein sequence similarities

Morphological similarities

(physical features) of living or fossil species

molecular data (DNA)

typically provides more accurate and reliable evidence than morphological traits

branch point/node

Branching indicates evolutionary relationships, and the point where a split occurs is called a

divergence event/speciation

Each node shows a _______ _____/______ and therefore represents the most recent common ancestry of any two groups or lineages

rooted

a single lineage at the base representing a common ancestor

Cladograms

constructed by using shared derived traits to distinguish different groups of species from one another

clades (monophyletic groups)

a group of organisms that descended from a single ancestor

Descent with modification

Organisms evolve from common ancestors and then diversify

shared ancestral character

If a characteristic is found in the ancestor of a group

derived traits

New characteristics that arise during evolution

indicate common ancestry

present in more than one lineage

outgroup

represents the lineage that is least closely related to the rest

parsimony

that the events occurred in the simplest, most obvious way

• pathway of evolution probably includes the fewest major events that coincide with the evidence

polytomy

A branch with more than two species coming off

gained, lost

Traits can be _____ and _________ multiple times over the evolutionary history of a species

taxon

Each level of classification is called a

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

taxon (listed from largest to smallest)

Binomial nomenclature

is the scientific naming of species

• Part 1 is its genus name, and part 2 is its species name