9-long tailed tits breeding Flashcards
what was the procedure carried out in Rivelin valley 1994-2019? (4)
- catch adults during nest building
- monitor all nests
- mark individuals with unique colour rings to identify
- blood samples for molecular genetic analysis to determine r and produce pedigree
what are non breeding seasons flocks composed of?
kin and non kin
according to hatchwell 2004 what do all birds breed in and what often happens?
monogamous pairs
often breeders fail as 75% nests destroyed by predators
how many eggs in a clutch and after how many incubation days do they hatch?
10 eggs
15 days
if the long tailed tits what is the difference if breeders fail early vs later in the season?
early: try to make a new nest
later: breeders become helpers to help another pair or are non helpers
what % of broods have helpers? and how do they assist?
50%
feed brood before or after fledging
what does the decision to breed again or help depend on?
date/time of year
what did 2002 findings reveal about the time of year and mortality?
- after 10th may dont breed again as later in season
- high mortality have faster life history and high reproductive rate, die young so generations occur quicker
what did Nam et al 2010 pedigrees and genotyping look at in terms of indirect benefits of helping? (5)
- 77% helped close kin
- usually M helped
- helpers invest more into close kin
- provisioning rate is according to relatedness
- increasing productivity increases kin selected benefit
what was Russel and Hatchwells 2001 kin preference experiment for indirect benefits? (3)
- manipulated breeding success to offer potential helpers choice of who to help
- failed M breeders in 16/17 cases chose to help relative nest
- active kin discrimination
what did Hatchwell 2014 discover about indirect kin selected benefits? (5)
- more successful means higher recruitment into breeding pop
- positive effect on probability fledglings survive to adult
- more helpers more productivity
- related so gain kin selected benefits
- helpers increase breeder survival
how do helpers increase breeder survival?
- lighten load of reproduction
- more likely survive to next year if have helpers
what did Meade 2010 discover about indirect kin selected benefits?
if M have helpers they provision brood less + have higher survival
why may there be no reproductive success in a current brood?
no brood parasitism and low rate of EPP
give 5 potential future direct benefits of helping
- help to buy flock membership
- winter survival
- breeding experience
- future mates
- future help
how do indirect benefits of helping compare to direct benefits and so what is preferred?
substantial indirect benefits but no direct benefits
- prefer to help kin and gain indirect kin selected fitness benefits from helping behaviour
what did MacColl and Hatchwell 2004 show when using lifetime reproductive success data to partition inclusive fitness?
most birds reaching adulthood achieved 0 fitness
- those that do, indirectly gain 20-25% fitness
to test hamilton’s rule what 2 potential helping costs did Hatchwell 2014 notice and which is correct?
- opportunity cost: NO
- survival cost: YES
- effect of helping on survival = -23%
- effect of helping on direct fitness= -0.029
to test hamilton’s rule what 2 potential benefits to brood and breeders did Hatchwell 2014 notice for helping behaviour?
- productivity increase (small effect of one helper)
2. load lightening, survivorship of helped breeders (small effect of one helper on M survival)
what can relatedness be measured with?
pedigrees or genotypes
helping is costly so what else can it be considered?
altruistic
what did Leedale 2018 discover for the generation of kin structured populations? (3)
- kin are clustered in the population
- nearby M more likely related to each other than distant M
- creates kin directed helping
when can kin selection only operate?
if are frequent interactions among kin
what did Sharp 2008 discover about natal dispersal in birds?
- limited and F biased
- disperse in groups with relatives
- 53% birds dispersed with relatives
- kin interactions can occur post dispersal as they dont move away from relatives
what did woodward find about long tailed tits kin discrimination despite migration?
still remained
autumn: 75% in kin groups
spring: 41% in kin groups
how does effective population size differ in other factors? + examples
small: low nest success, high recruitment, few breed successfully
large: high nest success, low recruitment
what did Beckerman 2011 life history simulation model show?
simulations will small effective pop size found higher relatedness after 40 years
give 4 reasons as to why LHTs of long tailed tits contribute to pop kin structure
- high rate of nest predation so few pairs successfully reproduce
- each brood has lots of related fledglings which can result in many recruits for the following year
- small effective population size
- timing of offspring mortality effects pop kin structure
how could constraints on breeding be measured?
compare coop across many years + look at what ecological/ life history factors co-vary with helping behaviour
list the 3 things that long tailed tit cooperation covaries with
- nest predation rate
- length of breeding season
- relatedness
what % of nests are predated and explain how nest predation covaries with coop (3)
40-80%
- determines no. of helpers + recipients
- if high predation then few nests helped
- coop peaks at intermediate level where both potential helpers and recipients
explain how length of breeding season covaries with coop (3)
- determines opportunity for independent breeding
- more likely successful breeding if early and less helpers
- helping negatively correlated with length of breeding season
describe the steps of the theoretical framework for long tailed tits (4)
- limited opportunity for successful independent breeding
- nest predation and short breeding seasons
- so failed breeders live in close proximity to kin
- kin selected fitness gains mean that failed breeders help to rear related broods
what type of breeding system do long tailed tits have and what else?
kin selected with active kin discrimination
what can be quantified?
indirect and direct components of inclusive fitness
what is satisfied?
hamilton’s rule
what does pop kin structure arise from?
limited coordinated dispersal and LH traits
what constrains independent breeding and drives helping?
+ what is it consistent with?
nest predation + short seasons
- ECH for evo of coop breeding