Evolution of Phenotypes

These flashcards cover key concepts related to the evolution of phenotypes, including types of selection, comparisons between species, and genetic influences on phenotypes.

What is interspecific comparison in the context of phenotype evolution?

It refers to the comparison of traits adapted to a habitat between different species that do not have a recent common ancestor.

What is convergent evolution?

A signature of adaptation where different species develop similar traits independently as a response to similar environments.

What does intraspecific comparison involve?

It involves comparing fitness between populations of the same species in different habitats.

What is phenotypic plasticity?

Changes in phenotype from a single genotype due to environmental influences.

What is developmental plasticity?

Changes in an organism's traits formed during development in response to environmental cues that are irreversible.

What is acclimatory plasticity?

An organism's response to short-term environmental changes.

What is seasonal plasticity?

Recurring changes in phenotype based on seasonal variations.

What are quantitative traits?

Traits influenced by multiple genes and environmental factors, typically normally distributed in populations.

What is the total variance (Vp) of a trait?

It is the sum of genetic variation (Vg) and environmental variation (Ve).

What is narrow-sense heritability (h²)?

It is the proportion of phenotypic variance due to additive genetic variance, ranging from 0 to 1.

What does directional selection favor?

It favors one extreme of a trait distribution.

What is stabilizing selection?

It favors intermediate traits and acts against extremes.

What does disruptive selection favor?

It favors both extremes of a trait distribution, leading to bimodal distributions.

What is the norm of reaction?

The range of phenotypes produced by a single genotype across different environments.

What are synonymous mutations?

Mutations in DNA sequences that result in no amino acid change.

What are non-synonymous mutations?

Mutations that lead to changes in amino acids, potentially impacting evolutionary consequences.

What are molecular clocks used for?

To estimate divergence times between species based on mutation rates.