Phylogenies Flashcards
list the different levels of the taxonomic classification system**
describe how systematics and taxonomy relate to phylogeny**
what are the components of the phylogenetic tree**
distinguish between homologous and analogous characters**
Homologous structures share a similar embryonic origin and organisms that share similar physical and genetic features are more closely related than those that do not
analogous structures have similar functions, but different structures and embryonic origin
what is the difference between ancestral and derived traits**
ancestral trait: similarly that is found in the ancestor of a group (all of the organisms in the taxon or clade have that trait)
derived trait: character found only in one group
what is the purpose of cladistics**
Is a system of biological classification that sorts organisms into clades: groups of organisms that descended from a single ancestor.
describe the maximum parsimony**
a concept used to choose events that occurred in the simplest most obvious ways
why is phylogeny important **
Phylogeny
The evolutionary history and relationships of an organism or group of organisms
describes the relationships of the organisms, such as to which species it is most closely related
what does a rooted tree show?
show a single ancestral lineage
what does an unrooted tree show?
shows the relationships among species, not the common ancestor
what does a root indicate?
An ancestral lineage gave rise to all organisms on the tree
What is a branch point
the point where a split occurs. represents where a single lineage evolved/diverged into a distinct new one
What is a Basal Taxon
lineage that evolved early from the root and remains unbranched
What is a sister taxa
two sisters stemming from the same branch point
