EcologyEcology

• Biosphere – entire part of the Earth where living exists. Soil, water, light, air.

• Ecosystem – interactions between living and non-living matter

• Community – group of interacting populations

• Population – individuals that belong to the same species

BiomesBiomes

• Pg. 220 of Princeton Review – know them

EcosystemsEcosystems

• Interactions between living and non-living matter

• Cycles – carbon, water, nitrogen

Carbon CycleCarbon Cycle

Water CycleWater Cycle

Nitrogen CycleNitrogen Cycle

CommunityCommunity

• Producers, Consumers, Decomposers – food chains

• Niche – an organism’s position and function in the community.

• 10% Rule – only 10% of energy is transferred from one level to the next

• Energy pyramid on pg. 223 in princeton review. Read paragraph on DDT.

Food ChainFood Chain

Pyramid of EnergyPyramid of Energy

Community EcologyCommunity Ecology

• Interspecific competition – competition between different species

• Resolved by:1. Competitive exclusion – Gause’s

principle – one individual outcompetes the other and replaces them in the niche

2. Resource partitioning – when different species can occupy a slightly different niche and live together

Resource partitioningResource partitioning

More ways to resolve competitionMore ways to resolve competition

3. Character displacement – a slight difference can change an organism’s niche and reduce competition. Ex. Bird beaks on the Galapagos

4. Realized Niche vs. fundamental niche – fundamental niche is the one without competition, realized is one that the organism settles for. Ex. Barnacles

Fundamental and Realized NichesFundamental and Realized Niches

PredationPredation

• True predator – kills and eats its prey

• Parasite – living off of the host without killing the host

• Parasitoid – lays eggs in a host

• Herbivore – eats plants, granivores, grazers, browsers

SymbiosisSymbiosis

• Mutualism – both benefit

• Commensalism – one benefits, while the other is neither helped nor harmed

• Parasitism – host is harmed, parasite benefits