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any action that be observed and described

fixed action patterns



durable change in behavior brought about by experience



associative learning

a change in behavior that involves an association between two events

classical conditioning

the paired presentation of two different types of stimuli causes an animal to form an association between them

operant conditioning

a stimulus response connection is strengthened

sexual selection

refers to the adaptive changes in males and females that lead to an increased ability to secure a mate

cost-benefit analyses

the benefit of access to mating is worth the cost of competition among males

dominance hierarchies

a higher ranking animal has a greater access to resources than a lower ranking animal


an area that is defended against attackers


the type of defensive behavior needed to defend a territory


the principles of evolutionary biology to the study of social behavior in animals


a behavior that has the potential to decrease the lifetime reproductive success of the altruist, while benefiting the reproductive success of another member of the society

king selection

adaptation to the environment due to the reproductive success of the individual's relatives

inclusive fitness

includes the personal reproductive success of the individual and the reproductive success of relatives

reciprocal altruism

making a minimal, short-term reproductive sacrifice in order to maximize future reproductive potential


members of a species are organized in a cooperative manner


an action by the sender that may influence the behavior of the receiver


chemical signals


the study of interactions between organisms with each other and with the physical environment


all the members of the same species that inhabit a particular area


all the populations found in a particular area


a community and its physical environment including both nonliving and living components


all the communities on whose members exist in air and water and on land


the statistical study of a population

population density

the number of individuals per unit area

population distribution

the pattern of dispersal of individuals across an area of interest


the nonliving and living components of an environment that supporting living organisms

population distribution

the pattern of dispersal of individuals across an area of interest

limiting factors

the environmental aspects that particularly determine where an organism lives

rate of natural increase

growth rate

biotic potential

the highest possible rate of natural increase for a population when resources are unlimited


all the members of a population born at the same time


the probability of newborn individuals of a cohort surviving to particular ages

age structure diagrams

diagrams for hypothetical populations that are increasing, stable or decreasing

discrete breeding

the members of a population only experience one reproductive event in their lives

continuous breeding

members experience many reproductive events throughout their lives

exponential growth

the number of individuals added each generation increases as the total number of females increases

logistic growth

a type of growth curve that is sigmoidal or S-shaped

density-independent factors

abiotic factors that have a drastic effect on the population

density-dependent factors

biotic factors that have a drastic effect on the population


Selection for life history traits that are sensitive to population density; also called density-dependent selection.

more-developed countries

countries with a good standard of living

less-developed injuries

countries with rapid expansion and a low standard of living

demographic transition

the sequence of events that effect the quality of life in a country

zero population growth

if couples have only two children, the population growth will be at zero

replacement reproduction

most countries grow at a rapid pace due to women have children very early


the assemblage of populations interacting with one another within the same environment


a place where an organism lives and reproduces

ecological niche

the role an organism plays in its community

generalist species

species with a broad range of niches

specialist species

species with a narrow range of niches

interspecific competition

the members of different species try to use a resource that is in limited supply

competitive exclusion principle

no species can indefinitely occupy the same niche at the same time

resource partitioning

decreased competition between the two species leading to increased niche specialization

character displacement

characteristics to be more divergent when populations belong to the same community rather than when they are isolated


a predator feeds on prey


the animal feeding on the prey


the animal being consumed by the predator


the ability to blend into the background

cryptic coloration

allows animals to blend into their surroundings


one species mimics another that possess an over antipredator defense


an intimate relationship between two or more species


a parasite derives nourishment from a host


takes nourishment from host


has nourishment stolen by parasite


a symbiotic relationship between two species in which one species is benefited and the other neither benefited nor harmed


a symbiotic relationship in which both members of the association benefit

ecological succession


pioneer species

plants that are invaders of disturbed areas

climax community


community stability

persistance through time, resistance to change, recovery once a disturbance has occurred

keystone species

organisms that play a greater role in maintaining the function and diversity of an ecosystem


the prevailing weather conditions in a particular region

rain shadow

an area of limited rain


a climate in which wet ocean winds blow onshore for almost half the year

montane coniferous forest

coniferous forest of a mountain

alpine tundra

the tundra near the peak of a mountain


a major type of terrestrial ecosystem

arctic tundra

highest-latitude Northern Hemisphere biome, where low, cold-tolerant plants survive with only a brief growing season


ground that is permanently frozen


biome just south of the tundra; characterized by a northern coniferous forest composed of pine, fir, hemlock, and spruce tree and acidic, mineral-poor topsoils

temperate rain forest

A coniferous biome with cool weather, dense fog, and high precipitation

temperate deciduous forests

biome, occupy regions that have warm summers, cold winters, and moderate precipitation, shed leaves in winter,

tropical rain forests

Characterized by the greatest diversity of species, believed to include many undiscovered species. Occur near the equator. Soils tend to be low in nutrients. Distinct seasonality: winter is absent, and only two seasons are present (rainy and dry).


plants such as mosses, lichens, and orchids, that grow on other plants but do not take nutrients from them


areas of land that tend to occur along coasts and have dry winters and receive most of rain during the winter


dense vegetation consisting of stunted trees or bushes


a region of grassland with scattered trees lying between the equatorial forest and the hot deserts in either hemisphere




wet swampy areas that are often flooded with water


areas that are wet for at least part of the year




wetlands dominated by either woody plants or shrubs


bodies of water classified by their nutrient status


the input of large amounts of nutrients into lakes

fall overturn

when the surface water cools and the deeper water is closer to surface temperature, so deep-water organisms move up

spring overturn

water temp increases, density barrier disappears, water, oxygen and nutrients free to circulate


aquatic, free floating, photosynthetic plants.


microscopic animals that swim or drift near the surface of aquatic environments


the area where a freshwater stream or river merges with the ocean

littoral zone

area that lies between the high and low water marks


the rising of cold water from deeper layers to replace warmer surface water that has been moved away

Southern Oscillation

a reversal of airflow between normally low atmospheric pressure over the western Pacific; the cause of El Nino

pelagic division

area that includes the neritic province and the oceanic province

coral reefs

areas of biological abundance found in shallow, warm tropical waters

benthic division

a region including the bottom of the sea and the littoral zones

hydrothermal vents

spots on the ocean floor where hot gases and minerals escape from earth's interior into the water

conservation biology

biology that studies all aspects of biodiversity with the goal of conserving natural resources


the variety of species living within an ecosystem

endangered species


threatened species

a species that could become endangered in the near future


different ecosystems

biodiversity hotspots

areas with lots of biodiversity


any environmental change that adversely affects lives

global warming

refers to an expected increase in temperature

keystone species



a population subdivided into several small , isolated populations

source population

a population that lives in a favorable area

sink populations

the environment is not as favorable

edge effect

reduces the amount of habitat typical of an ecosystem because the edges around a patch have a slightly smaller habitat

gap analysis

used to find gaps in preservation

population viability analysis

A method of predicting whether or not a population will persist

restoration ecology

The study and implementation of restoring damaged ecosystems

sustainable development


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