physical area in which an organism lives
functional role and distribution of an organism in a community; the organisms place in a biotic environment in relation to food and predators.
any set of conditions under which an organism can survive
describes conditions under which the organism really does occur (actual measurements)
The range, along an environmental gradient, within which the niche occurs. The niche is represented as a bell curve, and the optimum ecological performance is right in the middle, at the top of the curve
describes how much two niches overlap
What is Levin's Index?
measure of niche bredth which runs from a low of 1 to a high of infinity.
process by which organisms maintain a relatively stable internal environment
Heat/Temp Balance Equation=
H_Organism=H_m (+/-) H_env (-) H_e
heat of organism=metabolic heat plus or minus heat gain/loss from environment minus evaporative water loss
What factors affect the heat balance? (4)
Surface area:volume ratio, ambient temp vs. body temp, behavioral adaptations, and morphology.
organism obtains heat form external source
organism generates body heat internally
organism maintains constant internal temp no matter the external environment
organism's internal temp corresponds with external temp of environment
diffusion of molecules through a semipermeable membrane from a place of higher concentration to a place of lower concentration until the concentration on both sides is equal
greater solute concentration, movement of water out of cell
less solute concentration, water moves into cell
equal amount of water on both sides
Organism which have internal water and ion balances that track along with external environment.
organism which maintain constant internal water and ion balance over a wide range of external ion concentrations
What affects osmoregulation? (7)
body size, ambient ion vs. internal ion concentration, permeability of integument (skin), type of food eaten, temperature, activity level, and illness or poor health.
What are the 4 components of a territory?
Site attachment, exclusive use of the area, aggressive defense of area, and boundary switching.
at edges, animal more likely to retreat than attack
Arbitrary Rule hypothesis
territories are won according to some "arbitrary" rule, e.g. first to attack wins; territory holder wins; largest one
Resource-Holding Power Asymmetry hypothesis
territories are only obtained and kept by those
individuals that are larger and stronger
Value Asymmetry hypothesis
value of territory to resident is greater than the value of that territory to an intruder
long term movement from one location to another, it involves navigation and orientation
animals spend part of life span in one area, then the rest in a second habitat
similar to seasonal migration, but occurs irregularly
What is migration triggered by?
Changes is photoperiod, in seasonal migration this usually occurs twice
ability to move in correct direction
ability to determine where you are in relation to your final goal
What are the 3 minor types of migratory cues?
topographic, meterorological, and chemical
What are the 3 major types of migratory cues?
Solar, stellar, and magnetic (involves direction of earth's geomagnetic field lines, animals with this ability have magnetic crystals in brain or ear).
one male and multiple females
one female and multiple males
multiple males and females
Female defense polygyny
males exhibit strong intrasexual competition to obtain sole access to females
Resource Defense polygyny
males guard areas containing resources needed or wanted by females
Scramble Competition polygyny
males attempt to mate with as many females as possible by outracing other males
males defend small area that contains no resources or females (remember bowerbird)
one sex makes decision about which members of opposite sex to mate with (female)
individuals of same sex compete to gain access to other sex (male)
What are the 5 models of female choice?
direct benefits, good genes, runaway selection, sensory bias, and cryptic choice
females want ever larger values of a certain trait on males
males evolve trait that stimulates female's preference
females can choose which male gamete they want to fertilize their eggs