Week 3: Genetics and Evolution Flashcards
Behavioural Genetics
empirical science of how genes and environments combine to generate behaviour
Adoption Study
a behaviour genetic research method that involves comparison of adopted children to their adoptive and biological parents
Twin Studies
A behaviour genetic research method that involves comparison of the similarity of identical (monozygotic) and. fraternal (dizygotic) twins
Quantitative Genetics
the scientific disciple in which similarities among individuals are analyzed based on how biologically related they are
Heritability Coefficient
varying from 0-1, easily misinterpreted, meant to provide a single measure of genetics’ influence of a trait; measures how strongly differences among individuals are related to differences among their genes
Evolution
change over time
Natural Selection
Differential reproductive success as a consequence of differences in heritable attributes
Adaptations
traits/behaviours that evolved over time to increase our reproductive success
Intrasexual Selection
process of sexual selection - members of one sex compete with each other, and the victors gain preferential mating access to members of the opposite sex
Sexual Selection
evolution of characteristics because of the mating advantage they give organisms
Intersexual Selection
A process of sexual selection by which evolution (change) occurs as a consequence of the mate preferences of one sex exerting selection pressure on members of the opposite sex
Psychological Adaptations
Mechanisms of the mind that evolved to solve specific problems of survival or reproduction
Sexual Strategies Theory
explains how humans have developed different ways of approaching relationships and mating, like casual short-term relationships or long-term committed ones. It looks at:
The challenges men and women face in these different approaches.
The ways evolution has shaped behaviours to solve these challenges.
Gene
a specific DNA sequence that codes for a specific polypeptide or protein of an observable inherited trait
Epigenetics
study of heritable changes in gene expression or cellular phenotype caused by mechanisms other than changes in the underlying DNA sequence - marks include covalent DNA modifications and posttranslational histone modifications
Phenotype
an organism’s observable traits, like its appearance, behaviour, or physical features - shows how genes (genotype) are expressed in real life
Epigenome
the genome-wide distribution of epigenetic marks
Identical Twins
two individual organisms that originated from the same zygote and therefore are genetically identical/very similar
Genotype
the DNA content of a cell’s nucleus, whether a trait is externally observable or not
DNA methylation
chemical change to DNA where a molecule called a methyl group attaches to a cytosine base, usually at specific spots in the DNA (called CpG sites)
DNA methyltransferases (DNMTs)
proteins that add and maintain methyl groups on DNA
DNMT1 - keeps methylation consistent during DNA replication
DNMT3a and 3b - add new methylation patterns where needed
HATs and HDACs
HATs - enzymes that transfer acetyl groups to specific positions on histone tails, promoting an “open” chromatin state and transcriptional activation
HDACs remove these acetyl groups, resulting in a “closed” chromatin state and transcriptional repression
Histone Modifications
chemical changes to the “tails” of histone proteins; these changes, like adding acetyl, phosphate, or methyl groups, help control gene activity as part of epigenetic regulation
