lecture 15: adaptation Flashcards
(17 cards)
how do complex traits evolve?
influence of many environmental and genetic factors
require multiple components to function and multiple mutations to achieve a fitness advantage
regulatory networks consist of interactions between
genes, transcription factors, promoters, RNA
pseudogenization
gene copy is lost
dosage effect
increased protein product is
- unstable: gene copy is lost
-adaptive: gene copy is fixed
subfunctionalization
duplicated genes split the original copy between them
neofunctionalization
one of the duplicated genes evolve a new function
negative selection
removes deleterious alleles from a population
positive selection
advantageous alleles increase in frequency in a population
venom evolution
half of genes are housekeeping (fundamental) genes
half encode venom molecules
began evolving in a common ancestor and then diverged across species
what is the name of genes involved in venom evolution
defensin genes. ancestrally fights pathogens
genetic toolkits
ancient and conserved gene regulatory networks. consistently regulate the development of similar complex phenotypes.
hox genes
assign different developing sections of the body to different body parts
complex body plans
changes in timing and location of expression of developmental genes. alter shape or size of limbs
plant morphology
shape of leaves are a result of developmental genes
social behavior tool kit
feeding, chemical, mechanical, visual cues. worker-worker interactions effects
what factors constrain evolution
physical: environmental limits, pleitropy, existing developmental phenotypes, genetic variation
parallelism
convergent evolution that results from mutations to the same genes in different lineages
