Climate, Niches, & Community Interactions

Weather vs. Climate

Weather is the day to day conditions of the earth’s atmosphere. Climate is the year to year patters of temperature and precipitation.

A microclimate can form when environmental conditions vary over small distances.

Factors that effect climate:• Trapped solar energy• Latitude• Heat transport by winds and currents

Solar Radiation and The Greenhouse Effect

The balance between heat that stays in the biosphere and that lost to space determines earth’s average temperature.

The Greenhouse Effect allows solar radiation to enter our biosphere but slows the loss of reradiated heat to space.

If the greenhouse gasses rise, more heat is trapped and earth is warmed. If greenhouse gasses drop, so does the temperatures.

Greenhouse Effect Global Warming

GW is the enhanced greenhouse effect brought on by human activities such as the burning fossil fuels.

Latitude and Solar Energy

Near the equator, solar energy is the most intense because is almost

directly overhead at noon all year.

The poles have less direct sunlight, and therefore heat, from the sun

This unequal distribution of heat creates three distinct climate zones:

TropicalTemperate

Polar

The 3 ways communities interact are:

CompetitionPredationSymbiosis

Niche

Every species has its own range of tolerance, or the ability to survive and reproduce under a certain set of environmental conditions.

A Niche is the range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive

Competitive Exclusion PrincipalStates: No two species can occupy exactly the same niche in

exactly the same habitat at the same time.

If two species attempt to occupy the same niche, one species will be better and competing for these limited resources and eventually

exclude the other species.

By causing species to divide resources, competition helps

determine the number and kind of species in a

community and the niche each species

occupies.

Competition

Intraspecific – between the same speciesInterspecific – between different species

PredationPredator-Prey relationship: When one animal (predator) captures and feeds on another animal (prey). Predators can affect the size of prey populations in a community and determine the places prey can live and feed

Herbivore-Plant relationships : Herbivory is when an organism feeds on producers. Herbivores affect both the size and distribution of plant populations in a community and determine the places that certain plants can grow.

Keystone species: A species in the environment that is not usually abundant in the community but exerts a strong control over the structure of the community. Example: Sea Otters.

A century ago otters nearly disappeared and so did the kelp forests. Why?

Yellowstone Wolves Video Clip

Symbiosis

Any relationship which two species live closely together (and at least 1 benefits)

The three types are:Mutualism

CommensalismParasitism

Mutualisman interaction

between species in which BOTH

benefit (+,+)

Commensalisman interaction

between species in which one benefits, and the other is not helped or harmed

(+,0)

Parasitisman interaction

between species in which one benefits and one is harmed

(+,-)