How species How species interact:interact:

6-3 Species interaction6-3 Species interaction

. Five basic species . Five basic species interactions interactions

competition,competition, predation, predation, parasitism, parasitism, mutualism mutualism commensalism. commensalism.

Competition Competition

Competition between species Competition between species for food, sunlight, water, soil, for food, sunlight, water, soil, space, nest sites, etc. is space, nest sites, etc. is interspecific competition. interspecific competition.

With intense competition for With intense competition for limited resources, limited resources, one species one species must migrate; shift its feeding must migrate; shift its feeding habits/behavior or fact habits/behavior or fact extinction. extinction.

CompetitionCompetition As humans take more and more space, other As humans take more and more space, other

species are compromised. species are compromised. Over a long time, species evolve more Over a long time, species evolve more

specialized traits that allow them to use specialized traits that allow them to use shared resources at different times or shared resources at different times or in different ways or in different places; in different ways or in different places; this is termed resource partitioning. this is termed resource partitioning.

An example is that of insect-eating An example is that of insect-eating warblers in Maine forests that eat warblers in Maine forests that eat insects in specific parts of a spruce tree. insects in specific parts of a spruce tree. Owls hunt at night; hawks hunt during Owls hunt at night; hawks hunt during the day. the day.

Predator-prey Predator-prey relationships relationships

Individually prey is harmed, but Individually prey is harmed, but predation can help the population by predation can help the population by eliminating the sick, weak and old. eliminating the sick, weak and old.

Carnivores use pursuit of prey or Carnivores use pursuit of prey or ambush to capture prey. ambush to capture prey.

Some predators use camouflage and Some predators use camouflage and others use chemicals (venom) to capture others use chemicals (venom) to capture prey prey

Prey species escape predators in a Prey species escape predators in a number of different ways such as swift number of different ways such as swift movement, protective shells, movement, protective shells, camouflage or use of chemicals to camouflage or use of chemicals to repel or poison. repel or poison.

ParasitismParasitism Parasites live on or Parasites live on or

in another species. in another species. The host of this The host of this arrangement is arrangement is obviously harmed obviously harmed by by

the parasite can the parasite can contribute to contribute to biodiversity by biodiversity by controlling the size controlling the size of specific species of specific species populations. populations.

Ex. Ticks, leeches, Ex. Ticks, leeches, flukes, fungi, flukes, fungi, mites, horseflies…mites, horseflies…

MutualismMutualism Mutualism is a Mutualism is a

relationship which relationship which benefits both speciesbenefits both species; ; these benefits can be in these benefits can be in dispersing pollen and dispersing pollen and seeds for reproduction, in seeds for reproduction, in receiving food or in receiving food or in receiving protection. receiving protection.

Mutualism is not Mutualism is not cooperationcooperation; each ; each species exploits the species exploits the other. other.

Birds & African buffalo, Birds & African buffalo, elephants and elephants and rhinoceroses rhinoceroses

Clownfish and anemones Clownfish and anemones Fungi and plant root Fungi and plant root

associations called associations called mycorrhizae mycorrhizae

CommensalismCommensalism Some species Some species

interaction helps interaction helps one species but one species but does nothing for does nothing for the other; this is the other; this is commensalism. commensalism.

Examples of this Examples of this are the bromeliads are the bromeliads and orchids and orchids (epiphytes).(epiphytes).

Ramora & sharks.Ramora & sharks.