4-6 Species Role in Ecosystems

Concept to Understand•Each species plays a specific ecological role called its niche.

Ecological Niche•Every species occupy unique niches and play

specific roles in an ecosystem

Ecological Niche•Generalist species – can live many different

places, eat many things, tolerate wide variety of environmental conditions▫Examples: people, mice, cockroaches

Cockroach Information•Existed for 350 million years – 3,500 known

species•Highly adapted, rapidly producing generalists

▫Consume almost anything▫Endure food shortage▫Survive everywhere except polar regions▫Avoid predation

•Carry human diseases

Ecological Niche•Specialist species – can only survive in very

specific habitat▫Examples: most salamanders, giant pandas

Ecological Niche•Native species – naturally found in that

ecosystem

•Nonnative species – invasive, alien, exotic•Spread to new ecosystems (because of humans)

•Problems:•1. No predators•2. Kill native species which lack adaptation

Indicator Species•Indicator Species - Early warning system, damage to the environment causes this species population decline.

Keystone Species•Keystone Species - Significant role in ecosystem food web: large affect on other species in an ecosystem.

•Ex. Algae

Keystone Species•Elimination may alter structure and/or function of ecosystem

•Pollinators – bees, butterflies, hummingbirds, bats

Keystone Species

•Top predators – alligator, wolf, lion, sharks

Keystone Species•Keystone species create habitat/ ecosystem & help to keep it functioning.

Foundation Species•Create habitats and ecosystems•Ex. Beavers, Elephants, Seed dispersers