SR2: Bell et al 2014- benefits to dominant meerkats Flashcards
what does subordinate reproduction depress?
fitness of dominants
what is the meerkat species studied and how many groups?
S.suricatta
12
why do breeding dominants like to have non breeding subordinates ?
more helpers and provisioning of dominant pups by subordinate females
when subordinate breeding is suppressed what happens to dominants?
- improved foraging efficiency
- weigh more when pregnant
- produce heavier pups that grow quicker
why are subordinate females often targeted by dominants and how?
considered a resource
- aggression
- temporary eviction
- infanticide
how may subordinate breeding be related to reductions in dominant female reproductive success?
if breeding then reduced care for dominant offspring
how often were they observed? and where?
every week
S.Africa
what was injected into subordinates?
Depo-provera to prevent reproduction
what group size do they live in and how often do dominants breed and need to provision offspring for?
3-50
2-4 times per year
until 3 months old
over the years how did the treated groups differ?
in year 2 the ones that were injected with the hormone in year 1 were now the control
how long was the total treated duration?
9 months
did any of the treated females conceive?
no
how many dominant female breeding attempts were affected by the treatments
59
how did the dominant females attack treated subordinates?
at lower rates and were more tolerant of their presence and interrupted them less during foraging and evicted them less
which subordinates were more likely evicted by dominants?
larger and older as more likely to breed
how did the dominants likely detect the suppressed reproductive state of treated subordinates
olfactory cues
how may reducing eviction help?
evicted females don’t return so reduced helpers in group and -ve effect on pup development
where was a large ratio of female helpers to pups?
in treated groups
in terms of food and weight what were dominants in groups with treated subordinates like?
- captured more food
- gained more weight when pregnant
- pups born heavier
what would subordinate pups detract from?
available milk to dominant pups
what did treated subordinate females increase and why?
helping effort as cant invest in own reproduction
why do pups born heavier often have increased fitness?
weight determines competitive ability so likely will reach larger size in adulthood so dominance more likely
what low cost mecanism may you expect dominants to develop to restrain subordinate breeding ?
deny them access to the opposite sex
when are dominants only likely to tolerate subordinate breeding?
if little effect on their own reproductive success
why are the dominant efforts at suppression costly and so when do they occur?
if supressing then less success at foraging
only occur when necessary
what do the results suggest about plural breeding?
that it is rare
