Phenotypic Evolution

Flashcards about Phenotypic Evolution and Quantitative Traits

Quantitative Traits _.

Vary continuously or meristically and are often distributed normally (bell-shaped freq.).

Quantitative Traits often involves by many genes, alleles often interact in an ___.

additive fashion,

Environmental variation _ variation.

smoothes

Quantitative Traits: Selection alone can cause HUGE changes (even without new mutations) because of ___.

recombination

Variance is the __ for measuring variation

Statistical term

V = ∑ (deviations from the mean)2/(n – 1): Every individual same, no deviations from average, V = _.

0

VP refers to _

The variance of a trait

Mathematically VP is usually the result of both genetic and environmental factors. VP = + _

VG+VE

h2 = _

VG / VP

h² = VG/VP: If no _, then h² is 0.

VG

If amounts of VG and VE can vary with the _.

environment via Environment X genotype interaction.

Selection differential, S, is ___.

Difference between population mean and selected subpopulation's mean.

Response to selection, R, is ___.

Difference between original population mean and offspring’s mean.

h2=1, R will equal ___

S

Response to Selection: A population can respond to selection only if ___.

h2 ≠ 0 and VG ≠ 0.