animal interactions responses to the biotic environment

Animal Interactions

Responses to the biotic environment

INTERSPECIFIC

AGGRESSIVECompetitionPredator-preyParasite-host

CO-OPERATIVEMutualismCommensalismAntibiosis

Competition

Individuals of different species vie for the same resource in an ecosystem (e.g. food or living space).

Gause’s principle – no two species with exactly identical niches can co-exist for long in the same place

competitive exclusion (one species outcompetes the other) OR

adaptive radiation (one species adapts to a different niche)

Predator-prey relationships

• Evolution physiological & behavioural adaptations • Predator becomes a more successful predator• Prey becomes better at escaping predation

Birds of prey have developed extremely good eyesight to spot prey from a distance

PREDATORS 1 – PREY 0

Foxes are fast and quick-witted

PREDATORS 2 – PREY 0

PREDATORS 3 – PREY 0

Lynx vs rabbit

Lions hunt co-operatively

PREDATORS 4 – PREY 0

PREDATORS 3 – PREY 100

Speed is very advantageous for prey animals........

Methods of getting food

Let the prey come to you• Traps• Webs• Bait• Ambush• Sieves

Methods of getting food

Move after the prey• speed• teamwork• swarms• tools• appendages

Parasite-host relationships MosquitoEctoparasite

• Endoparasite

Parasitoid wasp lays eggs on caterpillar

INTERSPECIFIC

AGGRESSIVECompetitionPredator-preyParasite-host

CO-OPERATIVEMutualismCommensalismAntibiosis

Mutualism

• Bees pollinate flowers

Mutualism

• Tickbirds eat ticks

Commensalism

• Remoras attach themselves to sharks and hitch a ride, also eat leftovers

Antibiosis

• Large trees shading out smaller undergrowth• Animals trampling down the homes of smaller

animals• Human sewage disposal

“Go outside to do your business”