Topic 7.9 - Phylogeny 𖦹⋆｡°✩ Flashcards
what do phylogenetic trees and cladograms represent
both show evolutionary relationships between lineages
what is a phylogenetic tree
a branched diagram showing the evolutionary relationships amongst species
what can phylogenetic trees show
can show changes over time calibrated by fossils or a molecule clock
what is a cladogram
a diagram used to show evolutionary relationships amongst species
what is a clade
any group on a cladogram sharing a common ancestor
what do phylogenetic trees and cladograms represent
represent hypotheses and are constantly being revised under evidence
what traits can be used to construct phylogenetic trees/cladograms
traits that are either gained or lost during evolution
what traits are present in multiple lineages
shared characteristics, which represent common ancestry and are informative
what is the out-group and what do they provide
the lineage that is least closely related to the remainder of the organisms and they provide a reference of comparison that helps determine how the main group fits in the evolutionary tree of life
what is a node and what does it represent
where two lines meet. it represents the most recent common ancestor
what is a root
represents the common ancestor of all species on the phylogenetic tree or cladogram
what are the ways a phylogenetic tree/cladogram can be drawn
༻ diagonal, vertical, or horizontal lines
༻ orientation can be vertical/horizontal
༻ a node can be rotated
what does construction of phylogenetic trees and cladograms include
༻ morphological similarities from living or fossil species
༻ DNA and protein sequence similarities
what does molecular data provide
provide more accurate and reliable evidence than morphological traits
what is a derived character
a trait in a recent species, having evolved from an ancestral trait
