Indian Langur Monkeys Flashcards
monkey type
hanunuman (grey) langur
locations
jodhpur rajastan in north west india
nepal ramnagar
mating system (Jodhpur)
harem polygyny
reason for mating system in jodhpur
seasonal food provision= ecological stability= female desynchronize= male can monopolize
what are the pros of ecological stability for females
maintain constant food, body fat needed for lacataion, preganncy and care
effects of desynchronzied fertility for male
- create polygyny (male can monopolize)
- minimize sperm competition
- avoid sexual harrasment (females beat up males in breeding system due to limited sperm)
how does ecology effect polygynous/polygyandrous social systems?
food availibty= effects female synchronociity
nepal social structure
polygyandry due to high seasonality so females only ovulate in the summer/food abailiable systems
langurs and rank?
affects reproductive performance;
i.e. young females outrank old and get better food quality/body fat
i.e. dominant males have more access to females
infants lost per female to infnaticid
3.8
female counter strategies
- defend offspring
- promisciosu mating
- copulate while pregantn
- manipulate sex ratio (cryptic female choice)
- sychronzie ovulation to create polygyny
whats special about langurs
are colobine primate sin inidia that occupy diverse habitats (forest, mountain, urban) and are ecologically and socially flexible
why are births in india and srilanka all year long
non seasonal due to human food provisioning and general ecological stability
benefits of polygyandry
more cooperation better home range dfense counter-attack non resident males infant sharing lower infancitide (due to paternity confusion and EPC)
polygyny cons
less cooperation
- more competition and resident turnovers
more infanticide
why might infanticide be an adaptive strategy?
- resource competition
- parental manipulation
- sexual selection
- exploitation
explain how infanticide helps with resource competition
an infants death provides the killer with increased access to resting places, food mates and more care for their own infant
i.e. callitrichids and mere cats suppress reproductive capacbilities of subordinates to secure care for own infants
explain how infanticide helps with parental manipulation
when killing the infant improves the parental fitness, either by promoting the surival of another infant or reserving energy
i. e. illness disability
i. e. sex selective infanticide
explain how infanticide helps with sexual selection
when an infants own death increases the mating opportunities for the male killer and further reduces a competitiors reproductive success
explain how infanticide helps with exploitation
when an offpsring is used as a nutrtional or ristuatlistic resource in times of famimine/low resources
why might limited access to food resources push females to pursue reproductive asynchrony
reproductive asynchrony= redues food competition= pushesa way males as females can be monopolized= increases infanticide risk
bruce effect
termination of prenganges after exposure to unfamiliare males as a counter trategty to male infanticide
allows mother to maximize her reproductive output in a rapidly changing social environment
example of bruce effect in a primate
wild geladas (roberts 2012)
how might infanticide be avoided in humans?
adoption
oprhanages
abandonemnent
abortion
cinderrella effect in humans?
step children are more likelyl to suffer abuse/death on hands of step-parent
luckas, huchard 2014 opinion on infanticide
it reflects the forces of INTRASEXUAL selection as women defend using synchrononity
loose screw argument
by dolhinow; infanticide in langurs a reaction to stress of new commers/overcrodwing or killres are just a bit pathologically distrubed
tinbergen and lorenz view on infanticide
nonhuman animals are ‘better humans because they act for the good of the group’= cultural pessimism on aggression lead to ‘naturfolk’ in germans green party
volkers contradictions of Dolhinow’s Loose Screw Argument
- all indviiduals are health
- infanticide also occurs without human influence
- other species dont do it
- DNA analysis shows males attack unrelated victims
how was tinbergen-lorenz theory declined
conspecific killings exists;
switches view to gene-centered individual socioecology
out of america hypothesis of infanticide
infanticide caused by male competition over females (Hrdy)
radcliffe-brown + nazis
health of a society is determined by how well individuals are interegrated into the living body of group= moticated nazi ideology
conditions in ramnagar
no provisioning semi-green everest forest hot summer period no crop raiding sesaonality
langurs in ramnagar
are synchronized and mate seasonally dont crop ride have no clear signs of menstruation/ovulation interbirth ratios are 2.4 years (polygynandry)
langurs in jodhpur
females supress signs of visible mnstruation/ovulation IBI are 17.2 months infanticide occurs provisioning as seen as sacred/tourists are desynchronized (polygyny)
conditions in jodhpur
dry climate and monsoons
constanty water supply
less predators
crop raiding occurs
hrdy concealed ovulation hypothesis
concealed ovulation evolved as a counter-strategy to infanticide in polygyandrous systems
alenxander noonan concealed ovulation hypothesis
concealed ovulation and continious receptivity evolved to motivate pair-bonding/monogamy due to increased paternity uncertainity
