Chapter 3 Genetics & Evolutionary Foundations of Behavior Flashcards
Evolution
= long-term adaptive process (spanning generations) which equips each species for life in its ever-changing natural habitat
= changes in gene frequency between populations
gene
component of long molecules of a substance called DNA that
-> codes for a particular protein
GENES = basic UNITS of HEREDITY
(BESTANDTEILE / ELEMENTE von VERERBUNG)
genotype
the set of genes inherited by the individual
phenotype
the observable properties of an individual`s body & behavior
chromosomes
structures within cell nucleus that contain the genetic material (DNA)
mitosis
cell division (involved in normal body growth), produces cells that are genetically identical to each other
meiosis
(mEIosis) -> EIER
cell divison (involved in producing egg / sperm cells), results in cells that are genetically dissimilar & that each contain only half the number of chromosomes (of the original cell)
zygote
single cell that is formed when egg & sperm cell unite
- > the first, single-cell form of a newly developing individual
- > through mitosis zygote grows into a new person
identical twins
2 individuals who are genetically identical to each other bc they originated from a single zygote (fertilized egg)
also called monozygotic twins
fraternal twins
2 individuals who are not genetically identical to each other bc they originated from 2 seperate zygotes (fertilized eggs)
-> they are as gentically (un)similar as other siblings are to each other
but they develop simultaneously in the same womb
also called dizygotic twins
alleles
diff. genes that can occupy the same locus on a pair of chromosomes
- > can potentially pair with one another
dominant gene / allele
produces its observable effect even if person is heterozygous for that gene
recessive gene / allele
produces its observable effect only if indivual is homozygous for that gene
polygenic characteristics
MANY genes affect characteristic / trait
- > differences at many gene loci + environmental differences interact
- > a lof of DIFFERENT DEGREES of characteristics
f. ex. aggressiveness
- > (measured) scores for characteristics diplayed in a normal distribution (bell-shaped, frequency of scores tapers of symmetrically at both sides, so most ind. fall in the middle range and then some are very aggressive and some not aggressive at all)
normal distribution
bell-shaped frequency distribution
(mean, median & mode identical)
frequency of scores tapers of symmetrically on both sides
selective breeding
mating of individuals who manifest (aufweisen) specific characteristic to affect gene(tic makeup) of future generations
-> trait can be strengthened / weakened gradually over generations
- > can be done (un)deliberately
- > can be done to assess heritability
Epigenetics
epigenetic mechanisms determine which genes get activated and which don`t
-> every cell has same DNA but only some of it is active
F.Ex. every cell contains genes to grow eyes but they don`t grow on our liver
EPIGENETICS:
field that examines GENE-REGULATING ACTIVITY (with no changes to actual DNA, genes just get turned “on” and “off”)
that can have lasting effects for one or more generations
artificial selection
= selective breeding deliberately done by humans
animals / plants change according to our wishes
humans have been doing this for a long time which led Darwin to the theory that this occurs in nature as well
natural selection
= selective breeding due to changes in environment(al conditions)
animals / plants adapt due to obstacles in environment
(f.ex. predators, limited food supplies)
those with characteristics helping them to overcome these obstacles more likely to survive & reproduce
- > genes inherited to next generation and so on
- > individuals adapt to environment(al conditions)
mutations
errors that (occasionally & unpredictably) occur during DNA replication
-> “replica” different from original
(-> mutations original source of all genetic variability)
naturalistic fallacy
Trugschluss, Denkfehler, Irrtum
mistaken belief that everything that is natural (& particularly whatever is a product of natural selection) is right / good / moral
(belief that “natural” = “right”)
f. ex. “natural selection promotes self interested struggle among individuals -> selfishness is natural and right”
BUT Nature is not good / bad, moral / immoral
-> humans put these judgements on it
functionalism
explains functions ( / adaptive purposes) of mental processes & behavior
-> what do they do to promote survival & reproduction for individual
distal explanations (of behavior)
explains behavior on an evolutionary level
-> how did behavior evolve through evolution, how did & does it help ind. to survive and reproduce
=> FUNCTION of behavior
=> WHY is behavior there?
( => survival / reproductive function of behavior )
proximate explanations (of behavior)
how do mechanisms within individual (inside) or immediate environment(al conditions) (outside) elicit behavior
=> MECHANISMS of behavior
=> HOW does behavior occur?
=> stimuli & pysiological mechanisms through which behavior occurs
vestigial characteristics / traits
traits that still remain but no longer have a function
F.Ex. Body hair (in the past a lot, made us seem bigger in front of enemy)
adaptation
universal (& reliably developing) inherited feature that arose as a result of natural selection & helped to solve some problem of survival but has NO FUNCTION itself
F. Ex. Navel -> byproduct of umbilical cord, has no function itself
species-typical behavior
behavior pattern that is so characteristic for species that it can help identify it
f. ex. humans smiling, talking, two-legged walking
USED IN BOOK INSTEAD OF “INSTINCT” (bc its definition is not clear)
