Class Notes (811,690)
Canada (494,876)
Anthropology (1,653)
ANT100Y1 (945)

Garber reading.docx

4 Pages
Unlock Document

Dr.Joyce Parga

One for all and breeding for one: Cooperation and Competition as a Tamarin Reproductive Strategy – Paul A. Garber  Tamarins (Saguinus) – composed of social group containing more than one adult of each sex (many males and maybe more than one female) BUT in the breeding system only one female in the group gives birth (dominant female)  Emigration by both males and females in callitrichids  There is intense competition for reproductive success  Within-group intrasexual (between members of the same sex) aggression is rare (but there is still competition) Characteristics  Callitrichids – tamarins, marmosets, & Goeldi’s monkey (type of marmoset)  Small-bodied New World monkeys (South America)  29 species ranging in size from 120 g (pygmy marmoset) to 620 g (golden lion tamarin)  Claw-like nails  Intense female breeding competition (usually one breeding female per group)  Cooperative care of the young (many take care of the infants)  High reproductive output  Can eat: plant excludes (gums and saps), insects, small vertebrates  Males are caregivers, and there isn’t much sexual dimorphism  They were believed to be monogamous at first (not necessarily the case)  Smaller groups where thought to be more stable (bred more successfully)  It is now know that marmosets and tamarins can be monogamous (one partner for life), polyandrous (ooe female mates with multiple males) or polygynous (one male mates with many females)  In the wild they live in groups of 5 – 18 individuals (several males with few females)  Females mate with more than one male (chances for males to sire is not equal)  In some cases 2 females in a group are reproductively active  Cooperative behaviours are used to increase group cohesion, establish social and sexual bonds, and ensure the help of many adult helpers  Production of twins and 2 litters per year  For females the limiting factor for reproductive success is not only food but is also dependent on social dominance and access to infant-care  Intragroup (within group) social interaction in tamarins seem to be egalitarian, however during feeding the dominant female will have access to food first  Male to male aggression in Saguinus fuscicollis (tamarin) is quite rare (even when females were in estrus)  There is high cost to the breeding female if she carries her infants… the twins are carried together for the first few months and then are carried separately. That’s a lot of work since they travel long distances to forage for food. In the wild kin (family) and non kin will both help to transport the infants  Infant carrying is mostly done by males  The amount of carrying done by the mother and other non breeding females are approximately the same (results of one study)  Male carrying infants may be a form of intrasexual competition (female can assess the male)  There are costs to carrying infants  increased chance of predation, move slower  In tamarins both sexes participate in agonistic (aggressive) interactions with neighbouring groups (vocal battles, chases, visual display, scent marking, and fighting) – intergroup (between different groups) aggression is not rare  Work together to harvest fruits, they ate together without aggression  Infants can be given food by adults until 7 – 12 months  Adult males help provision young infants  this is important because infants may lack hand-eye coordination (brain growth during the first year is slow) – they may
More Less

Related notes for ANT100Y1

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.