COMMUNITY ECOLOGY

DESCRIBING BIOLOGICAL COMMUNITY

• Physical appearance
• Species diversity
• Niche structure

FACTORS THAT AFFECT SPECIES DIVERSITY

• Latitude
• Pollution in aquatic systems
• Habitat diversity
• Time
• Habitat disturbance

SPECIES EQUILIBRIUM MODEL

• Balance between 2 factors determines # of different species
• Rate which new species imigrate to island
• Rate which existing species become extinct

TYPES OF SPECIES

• Native- species that normally live and thrive in community
• Nonative, invasive, alien
• Species that evolved somewhere else and migrate accidentally or deliberatley
• Nonative example: african bee
• Indicator species- species that serve as warnings of danger for community

SPECIES CONT.

• Indicator species example: trout since they need clean water to survive
• Keystone species- species that have a large affect on the community
• Critical roles of keystone species: pollination, top predator
• Loss of the keystone species can lead to extinction and population crash
• Foundation species- species that play a major role in shaping community

SPECIES INTERACTIONS: COMPETITION AND PREDATION

• Interference competition-one species limtis another resources
• Resource partitioning- split up resource so species w/ similar needs can
• Access what they need
• Predation-one organism feeds off of another (predator and prey)

SPECIES INTERACTION: PARASITISM, MUTUALISM, AND COMMENSALISM

• Mutualism- a species interaction when both benefit.
• Commensalism- species interaction when one benefits but other doesn't.
• Parasitism- non mutual symbiotic relationship between species.

ECOLOGICAL SUCCESSION

• Ecological succession
• Primary succession-ecological succession thats never been used
• Secondary succession-ecological succession where plants have
• Been destroyed but soil is still good
• Pioneer species- first hardy species, that colonize a site

ECOLOGY STABILITY

• Inertia-living system to resist being disturbed or alerted
• Constancy- living population to maintain its size
• Resilience- living system to restore itself after disturbance