Primate Ecology

An overview of the ecological niches that primates occupy.

ecology (as defined by Ernst Haeckel)

total relations of the animal to both its organic and inorganic environment; how an animal, a population of an animal, or their sympatric community relates to its environment

ecosystem

the relationship of a particular community of plants and animals and its non-living environment

abiotic

the non-living components:

• water

• atmosphere

• soil

• climate

climate

the encompassment of temperatures, humidity, and rainfall; these are affected by location (i.e. latitude, altitude, oceans); this in turn affects the plant community

biotic

the living component:

• plant community

• animals

Why are plant communities fundamental to ecosystems?

The abiotic features of an environment determine the types of plants that can be grown in that environment. This plant community determines what types of animals can be supported in that environment since animals depend on the plants for food energy.

What must all ecosystems have?

A place with an energy source and a means to transfer that energy into usable forms.

Ex. A rainforest has its plants as the energy source and the sun to initiate photosynthesis. This energy flow is the definition of an ecosystem.

food chain

the sequence of transfers of matter and energy in the form of food from organism to organism

trophic level

a group of organisms that occupy the same position in a food chain

autotrophic level

the producers which can directly use solar energy:

• plants

• algae

• bacteria

heterotrophic level

the consumers who obtain energy either directly or indirectly from the plants

primary consumer

direct consumers of the energy source of an ecosystem:

• folivores

• herbivores

• frugivores

secondary consumer

indirect consumers of the energy source of an ecosystem:

• faunivores/carnivores

• insectivores

• omnivores

• scavengers/decomposers

biome

a major ecological zone characterized by specific climates and the types of plants and animal life they support

What is the most common biome for many organisms in the order primates?

The tropical biome, located in between the Tropic of Capricorn and the Tropic of Cancer. However, a tropical ecosystem in Africa may look different than a tropical ecosystem in South America.

ecological niche

the place or function of a given organism within its ecosystem

niche separation

the process by which natural selection drives competing animals into different patterns of resource use, resulting in different niches; this allows multiple species to coexist sympatrically

Ex. In Gabon, West Africa, researcher found that 5 sympatric nocturnal strepsirrhines avoided competition by eating different foods and/or eating in different rainforest levels

Leibig’s Law of Minimum

Factor(s) which are limited in supply (food, water, space, etc.) will limit the size of the population and may affect behavior and other adaptations

Ex. Folivorous howler monkeys cannot eat many leaves that contain secondary compounds

What fruit has been essential to early mammalian diet and subsequently to most primate diets?

Figs, b/c they contain a lot of fiber, carbohydrates, and sugar

How does the environment select its biome?

Through climate and location. Temperature and precipitation along with the environment’s proximity to the equator determines the biome and day length.

tropical rainforest

high rainfall, high temperatures:

• must have >= 100 in. (8 ft.) rain per year

• constant rainfall every month

• temperatures are consistently warm

• evergreen trees are the most common due to strong leaf cellular structure

rainforest composition

• emergent layer: highest of the treetops, much sun exposure

• canopy layer: a level plane where branches don’t overlap

• understory layer: branches and vines for suspensory locomotion

• forest floor: the ground, very little sun exposure

What limitations in the rainforest drive primates to select for fit adaptations?

• secondary compounds

• mechanical properties of foods

• food distribution

• predators

secondary compounds

toxic compounds which can be poisonous if eaten in large numbers (alkaloids) or can disrupt digestion (tannins)

What does it mean for the mechanical properties of foods to have the ability to limit primate population growth?

The physical characteristics of foods can limit how primates utilize the foods. For example, sakis and uakaris adapted their dentition and mandibles to be very robust and strong in order to eat hard, unripe fruits and nuts.