Week 9-10 Bio

Community Ecology

Ecology

Study of interactions among organisms and between organisms and their non-living environment

Ecosystem

All the living organisms in an area and the nonliving parts of the environment with which they interact

Ecological Community

Interacting populations of different species in a defined habitat

Exponential Growth

Unrestricted growth of a population that is increasing at a constant growth rate

Carrying capacity

Maximum number of individuals an environment can support, given its space and resources

Density-dependent factor

A factor that influences population size and growth depending on the number and crowding of individuals in the population Ex. predation

Density-independent factor

A factor that influences population size and growth regardless of the number and crowding within a population Ex. weather

Isle Royale, Michigan

Perfect natural laboratory, no human settlement, ideal distance from mainland

Random Distribution Pattern

Allow individuals to maximize their access to resources, avoid predation

Clumped Distribution Pattern

Happens when resources are unevenly distributed across landscape, strength in numbers

Uniform Distribution Pattern

Individuals keep distance from each other, territorial behavior

Exponential Growth

Unrestricted growth of a population that is increasing at a constant growth rate

Logistic Growth

Starts off fast, levels off due to environmental factors that limit ability to reproduce

Abiotic Factors

Nonliving components of environment

Biotic Factors

Living components of an environment

Food Chain

Linked sequences of feeding relationships in a community

Food Web

Complex interconnection of feeding relationships in community

Commensalism

Symbiotic relationship in which one member benefits and the other is unharmed

Symbiosis

Relationship in which two different organisms live together, often interdependently

Parasitism

Symbiotic relationship in which one member benefits at the expense of the other

Competitive exclusion

One of the competing species is unable to gain sufficient resources

Pollen

Small, thick walled plant structures that contain cells that develop into sperm

Pollination

Transfer of pollen from male to female plant structures so that fertilization can occur

Key Stone Species

An organism that has a large, critical impact on its ecosystems structure, stability, etc.

Niche

Space, environmental conditions and resources that a species needs in order to survive and reproduce

Competitive Exclusion

One of the competiting species unable to gain sufficient resources

Resource partitioning

Competing species make use of different resources

Specialist

Species may specialize in a particular food source

Generalist

Species may feed on a wide variety of food sources

Neonicotinoids

Systemic insecticides that are neurotoxins killing or paralyzing insects