Bio 2 chapter 40

Paedophryne swiforum

The caption Dr. Hullender provided for a 2008 photograph of a frog

Organismal ecology

Considers how organism structure, physiology, and behavior meet environmental changes

Population ecology

Considers factors affecting population size and change over time

Community ecology

A group of populations of different species in an area.

Ecosystem ecology

Community of organisms in an area & the physical factors they interact w/

Landscape ecology

A mosaic of connected ecosystems. Factors controlling exchanges of energy, materials, & organisms across multiple ecosystems.

Global ecology

Biosphere/Global ecosystem - sum of ALL ecosystems and landscapes on Earth

Population (yk)

Same species in defined area

Climate

An area’s long-term weather conditions

Abiotic factors

Nonliving chemical and physical attribues of environment

Biotic factors

Living components of an ecosystem

Terrestial Biomes

Tropical forests, savannas, deserts, grasslands, greens, beans, potatoes, tomatoes, yams, cornbread

Aquatc Biomes

Lakes, streams, intertidal zones, reefs, estuaries

Climograph

Displays a location's average monthly temperature and precipitation

Disturbance

An event that changes a community by removing organisms and altering resource availability

Abiotic Factors

Temperature, Oxygenm, Salinity, Rocks, Water

Biotic Factors

Predation, Herbivory, Mutualism, Parasitism, Competition

Density

Number of individuals of as species per unit area or volume

How do we measure population density?

Count all individuals in area, use sampling techniques

(ex. counting individuals in a few sample plots, use mark-recapture method)

Dispersion pattern

The way individuals are spaced within their area. Depends on resource distribution

Clumped

Aggregated in patches. Results from unequal distribution of resources or mating habits.

Uniform

Individuals are evenly spaced.

Random

Position of each individual is independent to others

Demography

Study of the vital statistics affecting population size

Birth and immigrants

Additions occur through…

Death and emmigrants

Subtractions occur through…

Cohort

Group of individauls born concurrently and tracked over lifetime

Survivorship curve

Graphic way of representing data

Type I curve

Shows low death rate early in life and high survivorship up to certain age group

Type II curve

Shows constant flux or risk of mortality at all ages

Type III

High death rate early in life. Many offspring, but little to no parental care

Black rockfish

Sebastes melanops

Semelparity

A.k.a. big bang reproduction. #’s of offspring are produced in each reproduction, after which the individual often dies

Iteroparity

Some organisms produce only a few eggs during repeated reproductive episodes

Delta N

Number of individuals

Delta T

Time

B

Number of births

D

Number of deaths

Exponential Growth

The exponential model of population describing an idealized population in an unlimited environment

J-shaped curve

Populations growing exponentially

Logistic Growth

Population groeth regulated by population-limiting factors

Life history

Comprises the age at which reproduction begins, how often it mates, and how many offsprings it makes

K-selection

Organisms live and reproduce around K and are sensitive to population density

R-selection

Organisms exhibit high rates of reproduction and occur in variable environments, where pop densities fluctuate well below K

Semel parity and iteroparity can be affected by

All of the above

Territioriality

Defense of a space sets limit on density

Predation

Excess predators limit factors

Metapopulation

Group of local populations linked by immigration and emigration

Density-independent factors

Factors whose occurence isn’t affected by population density

Birth, immigration, death, and emigration all alter population

Density

Interspecific interactions

Relationships between the species of a community; positive and negative

Competitive Exclusion Principle

Two species CANT COEXIST and one is eliminated

Niche

Population’s role in environment

Ecological niche

Sum total of an organisms use of abiotic/biotic factors

Fundamental niche

Defined by psychological capabilities

Realized niche

Defined by interactions with other species

Reso=urce partitioning

Species exploit same resource but in a different way

Character displacement

2 species have geographically overlapping populations

Batesian mimicry

Harmless species mimics a harmful one

Aposemtic coloration

Indicated by warning colors, sometimes associated with other defenses

Endoparasites

Live and reproduce inside host

Ectoparasites

Live on surface of host

Parasitioid

Parasite eventually kills the host