Chap. 26 - PP/Quiz Flashcards
Phylogeny
The evolutionary history of a species or group of species
What is systematics used for?
Classifying organisms
Determining their evolutionary relationships
What are the 3 schools of Systematics?
Traditional taxonomy
Numerical taxonomy
Cladistics or Phylogenetics
3 Schools of Systematics
a. Traditional taxonomy: based on ______ in ______
b. Numerical taxonomy: classifies organisms by ____ (numeric, ____ degree of similarity)
c. ______ or ______: based on shared, derived characteristics
a. similarities, morphology
b. similarity, quantifiable
c. Cladistics, phylogenetic
Are phylogenetic trees based on phenotypic similarity?
No
T/F Phylogenetic tree branch points mean exact ages
False
Just by looking at a basic phylogenetic tree, can you say which of the two lineages from a branch point evolved earlier?
No
What does a phylogenetic tree use to classify organisms?
“patterns or relatedness” of DNA versus taxa
Phylogenetic Tree:
Which grouping includes a common ancestor along with ALL of its descendants?
Monophyletic
T/F The polyphyletic looks at a common ancestor along with SOME descendants
False
Phylogenetic Tree:
Which grouping looks at only descendants WITHOUT including a common ancestor?
Polyphyletic
With cladograms, the internode represents a what?
Common ancestor
What does a node on a cladogram represent?
speciation event
Describe the difference between homologous and convergent/analogous traits:
Homologous traits are derived from a common ancestor, but convergent/analogous traits are similar but derived from DIFFERENT ancestors
George is looking at two species of turtles. He sees a trait (e.g., eye stripe) that is the same in both species. If he finds that the turtle from which both species came from has this same trait, than that eye stripe trait would be considered a ___ in both of the species he is studying.
homologous
While on trip to the Amazon River, Charlotte notices the wings of a big insect and a bat that came and ate it. Later, it occurs to her how much the insect’s and bat’s wing reminds her of a bird’s wing. Considering the relatedness of those 3 organisms, the similar wing trait in all three would be considered what kind of trait?
analogous
A researcher is looking at a similar trait in two closely related taxa that used to be different, but being in the same environment has led that trait in both species becoming more alike. This is specifically an example of ___.
parallelism
Homoplasy is when two species share a similar or same trait because they both got it from a recent common ancestor. T/F
False
Which methodology used to construct a phylogeny is based on having a common ancestor and evolved characters or traits used to distinguish different lineages from that common ancestor?
Cladistics
When looking at two species (A & B) in a phylogenetic tree that came from the same common ancestor and compared those two to a thrid species (C) that, while it does share some common character states with species A & B, it does not share a common ancestor. Species C would be considered a ___.
outgroup
