L5- Mechanisms on kin recognition Flashcards
what is kin recognition
differential treatment of conspecifics differing in genetic relatedness
what is the main theory for kin recognition
- is it true?
actor compares cue against template
actor compares recipients “cues” and actor compares cue against some internal template, if it matches prompts action based of kin recognition
what graph shows kin recognition theory
red line shows desirable recipient (kin), blue shows non desirable recipient (non-kin)
crossover shows an acceptance threshold, any kin passed acceptance threshold falls into rejection error, any non kin ahead of acceptance threshold is acceptance error.
what is the “generous strategy”
shows on graph generous strategy shows many acceptance errors, few rejection errors low cost:benefit ratio
seen in some helpers that assist non kin even though it confers no direct fitness benefits
- help is cheap
- kin selected benefits large
what is conservative strategy of kin recognition
graph shows conservative strategy, few acceptance errors, many rejection errors- high cost : benefit ratio
eg acts that are very costly may require
what is evidence for acceptance threshold model
honeybees, can show this,
honeybee colony have guard bees, they inspect every bee to ensure kin, if they dont like bee they attack it. They have guard bees as some other colony bees will come and steal honey (instead of foraging themselves)
as food availability increases, there are fewer guard bees, fewer flights and more generous acceptance thresholds
what is the greenbeard genes
idea that someone with greenbeard will help other people with green beard
recognition allele that-
signals itslef
recognises itself
directs cooperation towards bearers
is greenbeards real
all egg-laying females are Bb at locus Gp-9
-bb females die prematurely from intrinsic causes
-BB queens that initiate reproduction are killed by Be workers
(in this case recognition via odour)
Bb workers will recognise BB queens
what is the problem with green beards
players can create “falsebeards” individuals mimicing gene (ie greenbeard, get benefit of coop without cooping)
may not been individual favour to favour another individual just for sharing locus, might suppress that locus relation
croziers paradox, if there is a recognition cue that is good to have, would expect that gene to spread rapidly, eventually leading to gene reaching fixation, lackof variation
what is the armpit effect in markers indicating gene-sharing
thinking about MHC genes
often signalled by odour (armpit effect)
has been found in arctic char and xenopus, both prefer odour of other individuals that share same MHC genotype
how do mice urinary genes show genetic cues to kinship
similar to MHC genes- mouse urinary proteins (MUPs) are similar as are proteins that are inherited and mice recognise each other using these proteins
study gave female mice choice between two stimulus females, simply preference of sister or unrelated individual - sometimes sisters were familiar with the mouse sometimes not.In both familiar and unfamiliar mice, mice preferred to associate with mice of same MUP
breeding was involved to create females all related to each, but either matched the MUPs or didnt, found mice preferred to spend time with family with MUP matches, even when other mice were related but different MUPs
results suggest “self referent phenotype matching”
what is the “rule of thumb cue”
environmental cues to kinship
a rule of thumb or learned cue may be sufficiently reliable kinship cue
what is spatial cue for kinship
spatial cues (feed anything in my nest/territory)
BUT rule may exploited by inter- or intra- specific brood parasites
spatial cue may not be sufficient at all life stages in bank swallow, young nest until 18 days
- parents accept chicks switches between nests up to 15 days
- signature call develops at 15-17 days
-parental recognition based on signature calls
what are learned cues in kin recognition
learned cue= eg treat anyone i was reared with as kin, or treat anyone who sounds/smells like me kin
“colony odour” in social insects, learned cues in humans
learned kin recognition of kin from non-kin, bird song is individually disticitive, repeatable, family resemblance, adults discriminate kin from non-kin
- as netlings learn calls from parents so “siblings” have similar call
BUT cross-foster experiment show fostered nestings learn calls from carers so foster siblings have similar calls and sound like foster parents, helpers that help non-kin may do so because they sound like kin (acceptance errors)
when does active discrimination occur
only evolves when adaptive (ie when necessary)
