Phylogeny & Systematics Flashcards
what is phylogeny?
-evolutionary history of a species of group of species
-sorted by common ancestry, using fossil record and systematics
what is systematics?
-analytic approach to classifying organisms
-using morphological, biochemical, and molecular data to infer evolutionary relationships
where are fossil records discovered?
-sedimentary rocks: consists of layers called strata, can be used to date fossils
what is a morphological analysis?
-a study of the size/shape/structure of organisms to determine their biological relationships
-organisms that share morphologies or DNA sequences are more closely related
what is a molecular analysis?
an analysis of DNA sequences and a comparing of these sequences to determine the relation of two species
what is taxonomy? what is its ordering?
-ordering of organisms into categories
ordered: domain - kingdom - phylum - class - order - family - genus - species
what do branches in a phylogenetic tree represent?
the divergence of two unique species from a common ancestor, deeper branch points show greater divergence
what is polytomy?
an evolutionary relationship between species that is not yet determined / clear
what is a clade?
a group of species including the ancestral species and all its descendants
what is a paraphyletic clade?
a clade including the ancestor and some of its descendants but not all of them
what is a polyphyletic clade?
a clade including numerous types of organisms that lack a common ancestor
what are shared ancestral characteristics?
a character that originated in the ancestor of a taxon
what are shared derived characteristics?
-an evolutionary novelty unique to a particular clade (ex- vertebrae are not unique to mammals but hair is, therefore hair is unique to mammals)
what are the three taxonomic domains?
archaea, bacteria, and eukarya
