Chapter 26: Phylogeny and the Tree of Life Flashcards
What is phylogeny?
the evolutionary history of a species or group of species
What is Linnaean Classification of Organisms?
hierarchy based only on morphological similarities
What are morphological similarities?
physical similarities
What are the taxa of Linnaean’s hierarchy from smallest (most similar) to largest (least similar)?
species, genus, family, order, class, phylum, kingdom, domain
What does taxa mean?
group of organisms (ex- species, genus, family)
What is the first part of an organism’s scientific name?
the genus to which the species belongs
What is the second part of an organism’s scientific name?
the specific epithet unique to each species
What is the major problem with Linnaean classification?
It doesn’t specify relationships between these organisms, it just acknowledges their degree of similarity
What is the branch point of a phylogenetic tree?
point where lineage diverges, representing a common ancestor
What are sister taxa?
most closely related taxa on phylogenetic tree
What is a polytomy on a phylogenetic tree?
point where pattern of divergence is unknown to scientists; distinguished by a branch point that has more than 2 lines
What is a basal taxon in a phylogenetic tree?
lineage that diverges early in the tree so it originates near the common ancestor of the tree
What do “deeper” branch points represent on a phylogenetic tree?
progressively greater amounts of divergence
What 2 characteristics do scientists use to build phylogenetic trees and which is more accurate?
Morphological similarities, genetic similarities (more accurate)
How do scientists measure morphological similarities?
Fossil records, modern biology of the organisms
