Evolution and Phylogenics

What is the diagram used to show the evolutionary history of an organism called?

Phylogenetic tree.

When we see a phylogenetic tree with multiple branches from a single point we have a?

Star phylogeny and polygamy.

What is the taxonomic level of classification one level more general than family?

Order

What is the correct scientific name for the human species?

Homo sapiens

What traits do we attempt to make phylogenetic trees based upon?

Homologous

What does an ancestor and all of its descendants make up?

Monophyletic group.

We try to make the phylogenetic tree with the fewest evolutionary steps or the one that is the most?

Parsimonious

What is the process where we can see horizontal gene transfer in prokaryotes when a virus transfers genes?

Transduction

What is the term for evolution resulting in speciation?

Macroevolution

What is the sum of all alleles in a population?

Gene pool.

What are the assumptions of Hardy-Weinberg?

No mutations, no gene flow, no natural selection, no genetic drift, and random mating.

When we see something like an environmental disaster kill a large proportion of a population, we may then see?

A bottleneck event.

What would represent a genotype frequency under the H-W model?

p² + 2pq + q² = 1

What is the distribution of phenotypes in a population?

Population variation.

What can quickly decrease variation of alleles in a population and increase deleterious allele rates?

Inbreeding

What does fitness really refer to?

Production of viable offspring.

Founder Event

Starting a new population with a smaller subset that has fewer variations.

Stabilizing Selection

Selection against extreme phenotypes in the population, selection will decrease genetic variance.

Directional Selection

Selection for phenotypes at one end of the spectrum.

Diversifying Selection

Selection for phenotypes on both ends of the spectrum, selection against the middle.

Frequency-Dependent Selection

Selection for wither common or rare phenotypes.

Sexual dimorphism generally indicated higher ______________ than species where sexes look similar?

Sexual selection.

What is the process in which some individuals survive and reproduce better than others?

Natural selection.

What acts on populations?

Evolution

What are Darwin’s Four Postulates?

Traits are variable, traits are heritable, some individuals in a population survive better than others, and some individuals in a population reproduce better than others.

Convergent Evolution

Related organisms become very different from each other.

Divergent Evolution

Unrelated organisms independently evolve similar traits.

How do we witness evidence of evolution?

Vestigial structures, homologous structures, fossil record, and similarity of DNA.

Can individuals evolve?

No

Does evolution explain the origins of life?

False

What is a group of individuals that can interbreed and produce viable offspring?

Species

What is speciation that has occurred partly due to separation of two populations?

Allopatric speciation.

What is a postzygotic mechanism that helps maintain species barriers?

Hybrid sterility.

What does the presence of a hybrid zone indicate?

The presence of stability acting on a population