animal behaviour evolutionary perspective Flashcards
natural selection
process that results in increased survival and reproduction compared to that of competing organisms
some of this variation among traits can be
inherited so it has genetic basis
if trait increases fitness
it will be passed on
the change in gene frequency in a pop means the trait
becomes instilled
an action can be co-opted from previous actions, meaning
the action was previously used for one thing, now used for different context
ex courtship displays may be co-opted from ancestral movements
co-option of behaviour through evolution may reflect
domestication
adaptation
an adaptive trait may be a beneficial trait for which the ancestral function has been modified
- camouflage
- nocturnal
- mimicry
- hibernate
- migrate
some traits that were adaptive (needed) at an earlier time are
no longer adaptive
especially true during domestication ex cats hunting; they don’t need it now they r being fed
some traits exist because of the constraints put on them by other adaptive traits
give example
ex number of offspring; want to produce as many as possible BUT some large animals can only produce one due to constraints
some adaptive traits are result of ____ rather than natural behaviour
learning
- ex racoon learns food in house trash
behavioural adaptions of rabbits reflects their functional positions as
herbivores and prey animals
- ex freezing, thump to warn others, live in groups, burrows
ex of behavioural adaption in dogs
ladder of aggression; dogs adapted to show others their level of aggression
different continents selected for different dog traits from gray wold; led to
different breeds
- this is similar to adaption through natural selection except its adaption via domestication
3 selected adaptions via domestication of dairy cows
temperament, fitness, production
adaptions via natural selection may not always be optimal due to
development constraints
sexual reproduction is a
behavioural adaption as it is a major source of genetic variation
variety of offspring means
at least some will survive and reproduce in a changing world
for genetic shifts within a pop to result in biological diversity, the flow of genes must be
interrupted; can happen due to geographic barriers, resource shifts, mate choice or genetic change
ie if populations don’t interbreed, separate species forms
allopatric
barrier formed and new species forms due to isolation
ex darwin’s finches
parapatric
new niche entered, new species arises in the new niche, resource shifts (explorer pops vs parents pops)
sympatric
polymorphism (ie mutation) occurs and new species arises within the pop
- another ex is mate choice
are phylogenies ladders
no, radiations overtime
branches in phylogenies are
nodes, where last common ancestor was shared
