Biology 111 Final Exam (Hubbard)

Evolution

a change in population over generations.

Microevolution

change in the allele frequencies (or genotype frequencies) of a population over a generation.

Speciation

the development of new populations and species as ancestral populations divide and change.

Natural Selection

a cause of microevolution where one trait is selected for over another because that character is better suited for the environment in which the organisms are in.

Mutation

a cause of microevolution defined as changes in the nucleotide sequence.

Sexual Selection

a cause of microevolution defined as when one character provides a better advantage over another for the purposes of mating and reproduction.

Gene Flow

cause of microevolution defined as a change in the population’s allele frequency due to alleles entering or leaving a population through migration.

Genetic Drift

cause of microevolution defined as a drifting of alleles towards one allele or another in a population. occurs when there is random elimination of alleles.

Natural Selection

the microevolutionary change that is occurring in the population when the peppered moth population shifts from light form to dark form in response to soot in the environment.

Mutation

the microevolutionary change that occurred when some adults in a peppered moth were born with an orange thorax instead of dark or light. (new genotype)

Sexual Selection

the red coloration of cardinals has become more prominent in males than females. (females are dull and camouflaged)

Genetic Drift

a female mosquito is swatted and removed from the population (unable to reproduce) and her genes are unable to be passed down.

What are the steps of Speciation?

geographic/reproductive isolation, genetic divergence (mutation, natural selection, gene flow), formation of new species (unable to reproduce with each other when reintroduced)

The two components of a binomial (or latin binomial)

genus name (1, capitalized) and specific epithet (2, uncapitalized)

Phylogeny

the evolutionary history of a species or group of species.

Taxon

the named taxonomic unit at any level hierarchy.

Phylogenetic Tree

a branching diagram that represents that evolutionary history of a group of organisms.

Branches

the component of phylogenetic trees that represents an evolutionary lineage.

Node (branch point)

component of phylogenetic tree that represents the common ancestor of two evolutionary lineages.

Sister Taxa

the term for two groups of organisms that share a common ancestor that is not shared by any other groups (each other’s closest relative).

Monophyletic Group (clade)

a group in phylogeny that consists of an ancestral lineage and all of its descendants.

Paraphyletic Group

a group in phylogeny that consists of an ancestral lineage and some, but not all of its descendants

Polyphyletic Group

a phylogeny that consists of distantly related taxa but NOT their most recent common ancestor.