Motivation, competition and kin selection Flashcards
what is a motivational system
set of functionally related behaviours and their motivational control
how do motivational systems promote survival
- Maintaining the body and its internal state
- Dealing with the world outside the body
- Promoting reproductive success
what is the mechanism of external stimuli (ethological view)
sign stimulus, innate releasing mechanism, fixed action pattern
sign stimuli examples
-visual releasers
-auditory releasers
-chemical releasers
examples of learnt stimuli
-preferred foods
-spatial learning
-emotionally charged things/places
-causal factors as a result of reinforcement
what is Thomas Malthus’ principle of population
Populations could potentially grow exponentially, but in practice cannot do so
what does the principle of population assume populations are limited by
incomplete survival
reproduction
what can phenotype have an effect on (PoP)
success in competition
explain process of increase in populations
A factor in environment causes differences in reproductive success
variation is still random
more likely to survive and reproduce
over time number of organisms increase
what is reproductive success
the number of descendants an individual leaves
what does fitness refer to
change in frequency of allele over generations - related to average reproductive success of individuals it appears in
The evolutionary stable strategy
A behaviour that once common in a population cannot be outcompeted by any alternative behaviour
when may a behaviour evolve (ESS)
if the benefit and relatedness are greater than the cost
applications of kin selection
Used to understand why and what extent adults invest in children and grandchildren
Multi-cellularity
define eusociality
whole colony of individuals working together to fuel production of more
what is an evolutionary transition
Several free-living elements come together and start to operate as a collective
what is intragenomic conflict
different genes residing in the same genome have different agendas
Different genes give itself an advantage to all its competitors.
what is purifying selection
maintain distributions of phenotypes - selects against the extreme values of the character
what is stabilising selection
favours the intermediate variants within a population , occurs at ESS
what is directional selection
results in evolutionary change - favours one extreme phenotype
why does evolution not always produce optimal design
-time lags
-inconsistent selections with environment
-genetic correlations
example of genetic correlations
breeding out of undesirable behaviour e.g. aggression
heterozygote advantages
Reverse engineering
Experiments of nature
Comparative evidence
