Evolution Flashcards
Sociobiology: The New Synthesis
E.O Wilson (1975)
took which approach
took evolutionary approach of ethology. Focused on function (ultimate explanation) rather than stimuli (proximate)
“Give me a dozen healthy infants, well-formed,
and my own specified world to bring them
up in and I’ll guarantee to take any one at
random and train him to become any type of
specialist I might select – doctor, lawyer,
artist, merchant-chief and, yes, even beggarman and thief, regardless of his
talents, penchants, tendencies,
abilities, vocations, and race of his ancestors.”
who said this
John B Watson
what is the SSSM
standard social sciences model.
how evolutionary biologists view the idea that everything is a blank slate, everything can be learned.
Bio has nothing to do with behaviour and cognition
sociobiology: the new synthesis was accused of
other issues
biological determinism . was in conflict with cultural determinism
Enthusiastic just so stories was another problem (e.g. men are evolutionary more aggressive so should be expected to be aggressive.
- universal characteristics of human nature
- experience and expression of emotions
- spoken language
- status and roles including division of labour
- incest avoidance
- developmental trajectories
“branded” Evolutionary Psychology focuses on
evolved solutions to ancestral adaptive problems
Selection for evolved PSYCHOLOGICAL mechanisms, not behaviour
focus on human universals
Tooby and Cosmides
in adaptive mind book focus on
Modular and adaptive school of thought. e.g. unique brain networks for functions
- cognitive revolution
- innate psychological mechanisms
what dies EEA stand for
Environment of evolutionary adaptedness
what is environment of evolutionary adaptedness (EEA)
African Savanna during the Pleistocene (1.7 Ma - 10Ka)
99% of our homo history
Bowlby saw attachment of children as an adaptaion or pathology
adaptation
give an example of evolutionary mismatch or adaptive lag
having a fear of spiders now is not adaptive in UK.
But a fear of plug sockets or cars would be adaptive today
Critiques of evolutionary psychology
- not so different from sociobiology (panadaptaionism)
- out of date understanding of evolution
- EEA concept limited
- little known about EEA
- long evolutionary history before then
- diverse habitats
- not evident that hunter gatherers are reresentative (of out ancestral hunter gathereres from which we base our knowlege)
- Humans are still evolving
what is panadaptationism
saying that everything is adaptive e.g. write with left hand
Domain general psychology
- ability to learn is an adaptation (opposed to domain specific such as fear of spiders)
- cognitive abilities might be byproducts of more general abilities
- cognition involves integration across domains
behavioural ecology focus on
- adaptive responses to local environments ( contrasts with EEA)
- optimality and life history (organism change thru time) are adapted from behavioural ecology
- goal is to determine how differences among individuals can be due to optimality and fitness explanations (how do indivs make choices that should on the long run improve their fitness)
- not interested in proximate mechanisms (i.e., psychology)
Behavioural ecology started with
DeVore
- usuaully study small scale societies
- same approach as early ethnographers but
different theoretical background
- also use historical data sets (e.g., birth records)
to see how environment influences population
level behaviour
Behavioural ecology interested in
flexibility of individual behaviour
* facultative vs. obligate
* adaptability - degree to which a species can survive and reproduce in different environments
- evolution of behavioural flexibility (contrast with modularity)
- optimality - weigh costs and benefits of different strategies
- not conscious decision-making
e.g., sex did not evolve
because it makes us
think about babies
facultative vs. obligate
humans can facultatively live on the moon. Fish obligately live in water
what types of models do behavioural ecologists use
- formal models and hypothesis testing e.g. model predicts this behaviour will occour in this environment. Run the environment.
- proximate currencies e.g. calories to quantify fitness
- optimal foraging theory e.g. how long does it take species to forage
niche - environmental and way of life of an
organism
* greater overlap leads to__________
(e.g., prey size)
greater competition
ecophysiology
branch of behavioural psychology
how you make life history choices. e.g. growth or reproduction.
critiques of behavioural ecology
- focuses on current function(adaptive behaviours), not evolutionary history (adaptation)
Focus on behaviour, not psychology.
ignores constraints on adaptiveness (phenotypic gambit)
e.g. natural selection will always favour traits with high fitness. and there is a gene for each behaviour.
Levels of explanation
ultimate causation - refers to
proximate causation refers to
evolutionary levels of explanation
immediate circumstances
Four questions in levels of explanation
Ultimate (why questions)
- function
-evolution
Proximate (how questions)
- developmnent
- causation
function (adaptation) refers to
fitness value of a trait
evolution (phylogeny) -
evolutionary history of a
trait
development (ontogeny) -
traitʼs variation throughout development
- ontogeny recapitulates phylogeny (Haekel) e.g. development of embryo reflects evolutionary history
- causation (mechanism) -
immediate circumstances affecting a trait
e.g., stimuli that elicit a response, neurology,
hormones
4 key principles of evolution by natural selection are
- variability
- heritability
- surplus offspring
- nonrandom survival and reproduction
Fitness :
the four Fs
fighting
fleeing
feeding
fucking
fitness is
the differential survival nad reproduction of individuals
organisms do not always
seem to be perfectly adapted to their
environments
e.g.
adaptive (fitness) landscape
* the optimum solution can change
* getting from one to the other would involve a
reduction in fitness
pleiotropic:
one gene,
many effects
polygenic
many genes,
one effect
neo-Darwinism (the modern synthesis) is
the fusion
of Darwinian evolution by natural selection and
Mendelian inheritance
meiotic drive
(selfish genes passed on more than
predicted by random assortment, i.e., > chance)
evolution to a population
geneticist =
change in allele frequencies over time
convergent evolution
independant evolution produces analogous traits
homologies
adaptive radiation - similarity by descent - produces homologous traits
vestigial traits
traits remenants of out ancestral path that don’t serve a function anymore. e.g. we have appendixes for eating plants.
exaptations
traits that serve a different function than the one they were adapted for
developmental byproducts
traits that arise as a byproduct for a selected trait somewhere else
e.g. why do men have nipples.
maladaptations
e.g. cravings for sugar during EEA but not now.
phylogenetic inertia
limits on what can evolve due to previous adaptations. e.g. pig can’t grow wings. growing limbs spontaneously is impossible naturally.
Also genetic and physical constraints
is there genetic inevitability
the species and traits are not destined.
do adaptations occour for the greater good of a species
no. only benefits individual genes..
e.g. people do not donate to charity for the good of a species
naturalistic fallacy
goodness can not be reduced to natural properties
cannot be explained by biology
Social spencerism
“survival of the fittest”
argued natural selection could be applied to economics.
Not true
monkeys
replaced apes
during the
Miocene
Primate taxonomy
opposable big toes and thumbs
* flat nails, not claws
* locomotion is hind-limb
dominated
* dry nose
* forward
facing eyes
* binocular
vision
- primates have a _______ dentition
generalised
we are great apes (hominids)
* all apes have more flexible _____ for
brachiation and more ____ posture
shoulders
upright
what is our order, family, tribe , genus and species
Primates, Hominadae, Hominini, Homo, sapiens
when did humans and chimps diverge
aroung 5.8 million years ago
when did dinos go extinct
65 mil
socioecology
study of how ecological forces shape the size and structure pf social groups
primates have a slower life span than similarly sized mammals
e.g.
longer pregnancy, smaller litters, longer juvenile period, longer lifespan
different types of mating systems
solitary : female and her offspring come to mate with males
Polygyny: one male one male mates with multiple females
Mongomy : male and feemale and offspring
Polygny : multi male system multi female system
Polyandry. female with multiple mates
clumped resources (e.g. big fruit) leads to ____ competition
Contest competition. Dominant individuals fight for access
Dispersed resources leads to ____ competition
resource can also be mate
scramble
everyone rushes to grab what they can
Distribution of food effects—> _____ Regime which effect –> _____Relationships which effects what three actors
competitive regime
dominance relationships
- Value of alliances
- Female relationships
- Dispersal patterns (staying on territory)
humans are characterised by
- bipedal locomotion
- larger brains
- slower development
- language and culture
-derived dentition and jaw
musculature
How long ago did Australopithecines live
5.3 - 2.6 Ma
where did multiple Homo arise. Which groups
in Africa.
H. erectus, H. Heidelbergensis, H. neanderthalensis and maybe two others
is race a useful concept
No, not for modern humans
