bio quiz #2 - sept 18 Flashcards
extant species: (if line continues on)
still exist today
extinct species: (line is cut short)
none exist today
categories of all life on earth (most inclusive –> most specific)
domain
kingdom
phylum
class
order
family
genus
specific epithet
(d.k.p.c.o.f.g.s)
phylogeny
evolutionary history of an organism
phylogenetic tree
diagram showing ancestor-descendant relationships of organisms and groups of organisms
rooted tree
has a single ancestral lineage
branch point
represents where a single lineage evolved into a new one
basal taxon
lineage evolved early from root remains unbranched
sister taxa
two lineages stemming from the same branch
polytomy (star phylogeny)
more than two lineages from the same branch
systematics
organize and classify organisms based on evolutionary relationships
taxonomy
science of classifying organisms to construct internationally shared classification systems
binomial nomenclature
each species has two names (ex- Homo sapiens), genus + specific epithet, capitalized and lower case (italicized)
similarities in organisms
morphological and genetic (molecular) traits … help in making trees and drawing conclusions
homologous traits
derived from common descent (bird and bat wings)
cladistics
sorting of organisms into clades (groups descended from common ancestor) based on homologous traits
analogous traits
arise independently, insect and bird wings, “convergent”
monophyletic group
ancestor and all of its descendants
polyphyletic group
more than 1 lineage in one group (protists)
reading a tree or cladogram: adaptations lead to…
a new trait that becomes prevalent
reading a tree or cladogram: new variations continue to arise…
some are adaptive and persist, lead to new traits
reading a tree or cladogram: with new traits…
a new branch point is determined
reading a tree or cladogram: many individuals that descent from this point…
have this trait
shared ancestral character
trait found in an ancestor of a group
