Ecology review

The search for limiting factors

A biome is defined as, "a major regional or global biotic community, such as a grassland or desert, characterized chiefly by the dominant forms of plant life and the prevailing climate." There are a wide variety of biomes, including tundra, tropical and temperate rainforest, taiga or boreal forest, temperate forest, grassland, shrubland, savanna, and desert to name a few. Biomes are generally created by the interplay of temperature and precipitation in a given region on the Earth.

Grassland,Chaparral,Savanna, and Taiga

Tundra,Tropical forest, Wetlands, and Temperate forest

Responding to a threat

Chemical threat from injured fish

Zebrafish learned to associate smell of Pike with alarm

substance

Evidence of evolution. Only garter snakes in coastal areas eat

banana slugs

Energy cost and behavior

Male polymorphism

Altruism, the female is closer to her relatives and sounds arlams

more frequently

Population dynamics

I and II density dependent and III density independent

Trade -off between reproduction and survival

K-selection on the S-curve

Lizards evolved to live in different communities based on original variations in the population

Trait shift

Batesian mimicry -harmless mimics harmful

Mullerian Mimicry - two unpalatable species mimic each

other

Which is more diverse?

Food chain

Food web

Keystone predators- keep population in check

Otters are keystone

Succesion

Succession- Ecosystem changes over time after a disaster

Energy and chemical flow through a web. Energy is lost while chemicals recycle

Nitrogen limiting factor in the salt marsh

Only 33 Joules used for growth of new biomass

Rule of 10

Highest trophic level has least energy

Mauna Loa Lake

Ozone depletion

Since this picture was published the dolphin has gone extinct