Primatology - feeding + surviving

Carbs - fruit
aa - leaves
Fat and oil - seeds
Vitamins and minerals - fruit
Water - food, tree/water holes
Avoid toxins

Fluid dipping into holes in trees
Use wooden sticks / leaf sponges

Honey extraction
Termite fishing
Tool use - nut cracking, termite pounding, tortoise pounding, oyster cracking

Colour vision (ripeness)
Stereotypic vision

Source of carbs
BUT patchy distribution and quality (seasonal and due to competition)
Contest competition

Clumped resources
Resources scarce and valuable
Worth fighting over
Compete to gain access to these particular resources
Resources are monopolisable
Direct competition
van Schaik 1989

Source of proteins and fibre
Even distribution
Some components hard to digest
Hard to monopolise
Scramble competition

Dispersed (insects) and evenly (leaves) distributed resources
Scramble to get enough
Resources are not monopolisable
Resources not worth fighting over
No direct competition (it's indirect)
van Schaik 1989

Defence of either core area (high feeding intensity), food patches (high feeding intensity) or boundary (high food abundance)

Spatial memory
Euclidean maps show primates know position of food source and can approach it from different locations (almost acts as a reference point)
Niche partitioning - different strata and diet
Interspecific associations - sympatric situations (occupy same strata)
Anticipation - knowing when to leave to eat a certain food at a certain time (eg. figs in the early morning)

Grouping (dilution and confusion effect)
Sleeping sites (nest building, cliff sleeping)
Number of adult males (more males when higher risk of predation)
Alarm call systems (leads to different behavioural responses, referential calls to climb/come down from trees depending on predator)

Reciprocal evolutionary changes between pairs of species / groups as they interact with one another
Eg. shapes of flowers and shape of beaks of hummingbirds

Angiosperm co-evolution hypothesis
Visual predation hypothesis

our primate ancestors evolved key adaptations like forward-facing eyes, excellent colour vision, rounded, blunt teeth and fingers without claws, all for the purpose of eating and living from fruits
Sussman et al., 2012, Am. J. Primatol.

forward-facing eyes and grasping hands evolved in primates to allow them to eat insects in trees
Carmill, 1974, Science

ACOH = evolved to eat fruit
VPH = evolved to eat insects

Spit or swallow seeds - leading to dispersal

Eat colourful fruit with flesh and easy to swallow seeds
Lambert & Garber, 2006

High
Poulsen et al 2001

1991
Studied polyspecific associations between 6 primate species
Found the polyspecific groups were formed frequently for foraging
May help to optimise their foraging biomass
Foraging groups likely have an optimal size to maximise their foraging biomass and per capita food acquisition

Red colobus and diana monkeys form most associations during the height of chimp hunting season (predator)
Grouping and dilution effect
More vigilant and alarm calls
Also form more association during dry season - thinner foliage (increased crowned eagle predation risk)

Chance encounters of mutually tolerant species
Improved foraging efficiency
Reduced predation

Complementary antipredation skills
Predators may prefer one species