Cladograms
the branching point on a cladogram represents what?
a common ancestor
cladogram
a diagram that shows the evolutionary relationships among a group of organisms
derived character
a feature that evolved only within the group under consideration
shared character
a feature that is shared by all member in a particular group
clade
a taxonomic group with a single ancestor and all its descendants
what does cladistics use to establish relationships?
shared derived characteristics
phylogenetics
the analysis of evolutionary/ancestral relationships
systematics
the classifying of living organisms by their natural relationships
what must be true of organisms that have the most shared derived characters?
they are the most evolved
what variable is represented on the Y axis of a cladogram
time
what do cladograms represent?
hypothesis about evolutionary relationships
where is the most common derived character on a cladogram?
immediately after the out-group
how is the out-group determined?
it is the first branch of the cladogram with no shared characteristics
why is the out-group needed?
it serves as a basis of comparison between organisms
cladistics helps to classify what?
organisms
what is the in-group in a cladogram?
organisms with shared characters
what else can cladograms be based on?
DNA
shared derived characters are strong evidence of?
common ancestry