Lab 3 Flashcards
monophyletic group
- clade
- ancestral population and all of its descendants
node
where 2 lines intersect
- point of intersection
- this is what you count
macroevolution
evolution above the species level
adaptative radiation
single ancestral species rapidly diversifies into multiple new species
niche
defined as function role within an ecological community and includes all aspects pf a species related to survival and reproduction
what are some aspects of a niche
- habitat and climate characteristics
- food and shelter requirements
- how species interacts with each other and species in the community
resource partitioning
process in which a population reduce or avoid competition with others by shifting their resource use
what is the result of resource partitioning
groups that specialize on a particular ecological niche
what do the different niches drive
exert different selection pressures that drive evolution in different directions
what do most systematics use what to draw conclusions about ancestry
general morphology
cladistics
method to reconstruct the probable evolutionary pathway of a group of organisms
clades
groups of organisms that all share a common ancestor
what is a phylogenetic tree
representation of the evolutionary history of groups of individuals
how is time represented in phylogenetic trees
vertically
what does each line of a phylogenetic tree represent
a lineage
character states
particular variations in each character
ancestral traits
character in question is present in the most ancestral member of the group
derived character
trait that has changed from the ancestral condition
plesiomorphic
another term for ancestral character (1 taxa)
apomorphy
another term for derived traits (1 taxa)
synapomorphy
derived trait (several taxa in group)
sympleiosmorphy
ancestral trait (several taxa in a group)
parsimony
simplest tree
convergence
same character state can evolve separately
reversal
sometimes derived character state can revert back to ancestral condition
polytomy
tree with three or more taxa emerging from single node
- relationship among these taxa is known
outgroup
species or group of species that are closely related to organisms you are classifying but not directly related
paraphyletic group
group of species that includes an ancestral species but not all of its descendants
- exclude a taxa
- man made
- make group that makes sense based on characteristics
if you expand or change monophyletic group, what happens to shared and ancestral traits
they can change
- relative to group you are talking about
no currently living population is
an ancestor of another currently living population
