BIOL205Z in lecture notes cards Flashcards
comparative method
- look at species that have two different eclogies but share the same trait
- or look at species that share an ecology but don’t share a trait
evolution of menopause
-humans: some sort of mismatch between the rate at which follicles degrade and lifespan
-killer whales post reproduction representation is close to o.31, cease reproducing at 40 but can live to 70’s/80’s
grandmother hypothesis
-post reproductive females promote genetic contribution to further generations
-menopause, outcome of kin selection?
-reproductively active grandmother may impose fitness costs in grandchildren
examples of menopause
-killer whales
-baluga whales
-narwhals
-pilot whales
pedigree
shows how individuals descended from two ancestral Individuals
phylogeny’s
-not individual anymore
-has tips which each represent a single group of known species
-purpose is to reconstruct relatedness between species and when they diverged from one another
evolution of infanticide
-a homoplasy as there was no evidence of it in the common ancestor
-occurs in the majority of non-anual breeders, 76% of 97 species
-commited more in stable mixed sex groups
synapomorphies
-shared derived homologies
-outgroup doesn’t have the trait
-e.g. lactation, seen in all mammals but no birds
symplesimorphies
-shared ancestral homologies
-outgroup also has the trait
-e.g. backbone, seen in all mammals and all birds
American vole
- 2 species: prairie and montane
-one species is monogamous and the other is promiscuous
-look similar morphologically, but morphological features evolve slower
mongoose
-evolved extreme birth synchrony
-reduces risk of infanticide, other mothers will kill pups If they’re born early
transposons
-insert extra copies of themselves around the genome
-discovered when looking at mosaic patterns in maize
alu element
increases the likelihood of mutations occurring in humans
segregation distorters
-kill of sperm that don’t contain the distorter in order to increase their frequency in the next generation
-two tightly linked genes= toxin + antidote
X-linked
X chromosomes survive whilst killing off Y chromosomes
Malaysian stalked eyes flies
-females prefer males with eye stalks further apart
-eye stalk length is a good indicator of whether males have suppressor gene
drosophila
-In populations where females are mating with multiple males, there are less sex ratio distorters in the population
-SGE’s major driver behind evolution of polyandry
lions food
-size of pride variable
-abundance of prey so large number of lions is supported
tigers
scarce food so only one to two individuals supported
monogamous relationships
-splendid fairy wren
- 70% of offspring might not be from parent feeding from parent feeding them
-mute swan
-100% monogamous
long tailed manakins
won’t look at male when there is only one of them
cultural evolution
-Behaviour picked up in social groups
-Doesn’t lead to changes in gene frequencies directly, but could be genetically good learner
teaching in the field
-Bees learning to pull on a string and get sugar solution
oPut that bee back with other individuals and via social networking, they will all know how to get the sugar syrup
house sparrow
-males have a badge on their chest
-Size of badge determines how dominant you are
-Scaled 1-5, 5 being the most dominant
successful cheats
-Hoverfly looking like wasps, unlikely to be eaten as predator assumes you are a wasp
-Cuckoos laying their eggs in other birds’ nests
mobbing call
gets all individuals to join in and attack a predator
identity
penguins in breeding groups able to pick up call of chick and mate in a large group
metacommunication
dogs will do play bo when it wants to play, so that you don’t mistake their behaviour for aggression
goats
-Vocalisation depending on mood
-Sad goat, different frequency
-Happy and sad, same call but different frequency
corticosterone on parents behaviour
-if parent is in really bad state, their priorities will change
-parent will provide less care to offspring if they are injected with corticosterone
-go in to emergency life history stage in order to survive
hormones and aggression
-Females more aggressive, but testosterone levels higher in males
-Females: lower progesterone, more aggressive you are
-Higher levels of progesterone: priority will be incubation, not aggression
Challenge hypothesis
Environment and social behaviour impact production of testosterone
Fighting in mice
-Mice who won previously have upped testosterone levels
-Made them more likely to win again
-Drove winners effect
Explanations of altruism
-group selection
-social contract models
-selfrish teamwork models
insight
the ability of an animals to consider a set of information and to derive from that information a novel solution to a problem
