10-kin recognition Flashcards
at what level of biological organisation do recognition systems play a role in?
all levels
what can vary widely?
strength of selection on active kin discrimination
what depends on discrimination ability and recognition system?
adaptive decisions about mate choice, coop investment + social affiliation
what is kin recognition?
differential treatment of conspecifics differing in genetic relatedness
how can indirect fitness benefits of kin selected behaviour be maximised?
by effective discrimination of kin from non kin
what do benefits and costs of discrimination vary according to?
ecological and evolutionary context
according to Reeve 1989 what are the 3 components to the system involving the actor and recipient?
- production component: cues in recipients allowing actors to recognise them
- perception component: sensory detection of cues by actors and phenotype matching of cue to template of fitness enhancing or reducing recipients
- action component: action performed that depends on similarity between actors template and recipients cue
in terms of the acceptance threshold model what is a generous strategy?
- many acceptance errors
- few rejection errors
- low cost:benefit ratio
in terms of the acceptance threshold model what is a conservative strategy?
- few acceptance errors
- many rejection errors
- high cost:benefit ratio
in terms of the acceptance threshold model what is likely to overlap?
cues of desirable and undesirable recipient
what is rejection error?
relatives to the right of the threshold are being rejected and aren’t helped
even though it confers no direct fitness benefit what do some helpers do?
assist non kin
what % of long tailed tits help non kin?
22.7%
what is the honeybee evidence for acceptance threshold model studied by Downs and Ratneiks 2000? (3)
- colony guards adjust rejection/acceptance of bees entering the colony according to risk of nectar robbery
- those trying to steal are often killed by guards
- if fewer guards, fewer fights + more generous acceptance threshold as food availability increases
how is perception and action component of recognition determined?
genetically or environmentally
according to dawkins 1976 what are green beard genes?
recognition alleles that signal themselves, recognise themselves in other individuals and have direct cooperation to other bearers of the gene
what is Keller + Ross 1998 fire ant example of green beard genes? (3)
- egg laying F at Bb locus
- bb F die prematurely
- BB queens who initiate reproduction are killed by Bb workers
according to Wang et al 2013 what is a green beard gene?
a social chromosome that encompasses 616 genes in a non recombining region where recombination is suppressed due to chromosomal inversion
what is the armpit effect by Darwin 1976?
‘markers indicating gene sharing’
- comparison by actor self inspection of genetically determined cues vs template to assess relatedness
what are MHCs?
highly polymorphic and detected by scent
what can indicate preference for the same MHC type and for what 2 species?
- how do juveniles discriminate?
tests of discrimination among siblings
- arctic char
- xenopus laevis
- juveniles discriminate among siblings preferring odor of those with same MHC genotype suggesting genetic cue to kinship causing discrimination
what is Green et al 2015 house mice example for genetic cues for kinship? (5)
- genes encoding mouse urinary proteins (MUP) inherited at tight linkage units
- F move between cages with sister, unrelated F, neutral cage
- F prefer to nest with F that share MUP genotype
- results indicate self referent phenotype matching
- related to similar smell
what is MUP?
species specific kinship marker
what is self referent phenotype matching?
discriminating in favour of conspecifics with a phenotype that matches your own
what is a more widespread mechanism than genetic cue to kinship?
environmental cue to kinship
what are spatial environmental cues to kinship?
‘feed anything in my own nest territory’
- rule exploited by intra or interspecific brood parasites
- likely those in your nest related
how may spatial cues not be sufficient in Beecher et al 1981 colonial bank swallow example? (5)
- shortly before leave nest offspring develop signature calls recognised by parents
- cues used by parents change through time
- signature call develops at 15-17 days
- parental recognition based on signature calls
- switch from spatial cue to vocal cue
what are learned environmental cues to kinship?
‘treat as kin if sound, smell + appearance familiar’
- honeybees use environmentally acquired + learned colony odours for discrimination
- humans avoid close childhood associates as future sexual partners
what can experimental tests of learning for kin recognition use?
cross fostering of nestlings
Sharp et al 2005 using cross fostering of long tailed tits for learning kin recognition what do the calls allow?
discrimination of kin from non kin
why do long tailed tit siblings have similar calls?
nestlings learn calls from parents
what are long tailed tits calls like
calls are:
- individually distinctive
- repeatable across years
- family resemblance
what were the calls like for fostered nestling in the cross fostering experiment?
fostered nestling learn calls from carers so foster siblings have similar calls and sound like foster parents more than true parents
what did Leedale et al find for why helpers may help non kin?
they sound like kin
what did Jouventin et al 1999 discover for recognition in king penguins?
- playback experiments to chicks with modified parental calls
- showed chicks use frequency modulation especially shape of syllables for recognition
what did Griffin + West 2003 do for kin discrimination?
meta analysis within species finding significant kin discrimination across studies but is variable
according to cornwallis 2009 what is expected in species such as long tailed tits that are surrounded by lots of non kin?
high levels of kin discrimination
when does active kin discrimination + recognition only evolve?
when adaptive
for variation among coop breeder what is discrimination correlated with?
probability of making errors
under what circumstances can any young be fed on natal territory?
if helpers philopatric in stable groups on stable territories and any young present can be close kin so no need for active kin discrimination
how does the strength of selection for kin recognition + mechanism vary and what does it relate to?
across taxa
related to ecological + social contexts experienced
