Ecology IB

Behavior

An action carried out by muscles under control of the nervous system.

Ultimate causation

Why a behavior occurs in the context of natural selection

Ethology

The study of animal behavior observed in a natural environment.

Behavioral ecology

The study of the ecological and evolutionary basis for animal behavior.

Tinbergen’s experiment

The fish experiment with competition between the different male fish

Fixed action pattern

A sequence of unlearned acts directly linked to a simple stimulus

Sign stimulus

The trigger for a behavior is an external cue called

Migration

A regular long-distance change in location.

Circadian clock

An internal mechanism that has a 24-hour periodicity

Circannual rhythms

Behavioral rhythms linked to the yearly cycle of seasons.

Signal

A stimulus transmitted from one organism to another.

Communication

Transmission and reception of signals between animals

Pheromones

Animals that communicate through odors or tastes emit chemical substances called

Innate behavior

Behaviors that are performed by all individuals the same way each time

Cross-fostering study

The young of one species are placed in the care of adults from another species in the same or a similar environment

Learning

The modification of behavior as a result of specific experiences.

Imprinting

The establishment of a long lasting behavioral response to a particular individual or object.

Sensitive period

A specific time period in development where imprinting occurs.

Spatial learning

The establishment of a memory that reflects the environment’s spatial structure

Cognitive map

A representation in an animal’s nervous system of the spatial relationships between objects in its surroundings.

Associative learning

The ability to associate one environmental feature with another is called (EX- Pavlov’s dog experiment)

Classical conditioning

An arbitrary stimulus becomes associated with a particular outcome

Cognition

The process of knowing that involves awareness, reasoning, recollection, and judgement

Problem Solving

The cognitive activity of devising a method to proceed from one condition to another in the face of real or apparent obstacles

Social learning

Learning through observing and interpreting the behavior of other individuals

Culture

A system of information transfer through social learning or teaching that influences the behavior of individuals in a population.

Foraging

Food obtaining behavior

Optimal foraging model

To study the ultimate causation of foraging strategies, biologists can apply this type of a cost-benefit analysis

Monogamous

One male mating with one female

Polygamous

An individual of one sex mating with several of the others

Sexual dimorphism

The extent to which females and males differ in appearance, typically varies with the type of mating system.

Mate-choice copying

A behavior in which individuals in a population copy the mate choice of others.

Game theory

Evaluates alternative strategies in situations where the outcome depends on the strategies of all the individuals involved

Anti diuretic hormone (ADH) or vasopressin

Peptide that is released during mating and binds to a specific receptor in the central nervous system.

Altruism

Describes a behavior that reduces an animal’s individual fitness but increases the fitness of other individuals in the population.

Inclusive fitness

The total effect an individual has by providing aid that engages other close relatives to produce offspring

Coefficient of relatedness

Equals the fraction of genes that are shared

Hamilton’s Rule

Natural selection favors altruism when the benefit to the recipient multiplied by the coefficient of relatedness exceeds the cost to the altruist. When rB > C

Reciprocal altruism

Exchange of aid between different animals who aren’t related

Ecology

The scientific study of the interactions between organisms and the environment

Environment

Other organisms as well as the physical aspects of an organism’s surroundings

Organismal ecology

Includes the subdisciplines of physiological, evolutionary, and behavioral ecology, is concerned with how an organism’s structure, physiology, and behavior meet the challenges posed by its environment

Population ecology

Analyzes factors that affect population size and how and why it changes through time

Community ecology

Examines how interactions between species affect community structure and organization

Ecosystem ecology

Emphasizes energy flow and chemical cycling between organisms and the environment

Landscape ecology

Focuses on the factors controlling exchange of materials, energy and organisms across

Global ecology

Examines how the regional exchange of energy and materials influences the functioning and distribution of organisms across the biosphere

Biosphere

Global ecosystem, sum of all the planet’s ecosystems and landscapes

Climate

The long-term prevailing weather conditions in a given area

Microclimate

Very fine, localized patterns in climate conditions

Abiotic

Nonliving factors that influence the distribution and abundance

Biotic

Living factors that influence the distribution and abundance of life on earth

Climate change

A directional change to the global climate that lasts three decades or more

Biomes

Major life zones characterized by vegetation type in terrestrial biomes

Climograph

A plot of the annual mean temperature and precipitation in a particular region

Ecotone

The are of intergradation of two different biomes

Canopy

The top layer of trees in a forest

Disturbance

Is an event such as a storm, fire, or human activity that changes a community

Photic zone

The region where there is sufficient light for photosynthesis

Aphotic zone

Region where little light penetrates

Pelagic zone

Photic and aphotic zones lies this area

Abyssal zone

The part of the ocean 2,000-6,000 m below the surface

Benthic zone

Bottom of all of these aquatic zones

Benthos

Communities of organisms collectively called this living in the benthic zone

Dettritus

A major source of food for many benthic species is this dead organic matter

Thermocline

In the ocean and most lakes, a narrow layer of abrupt temperature change is called this

Turnover

The movement of something into, through and out of a place, the rate at which a thing is depleted and replaced

Dispersal

The movement of individuals or gametes away from their area of origin or from centers of high population density

Population

A group of individuals of a single species living in the same general area

Density

Pattern of spacing among individuals per unit area or volume

Dispersion

Pattern of spacing among individuals within the boundaries of the population

Mark-recapture method

Used to estimate the size of wildlife populations

Immigration

The influx of new individuals from other areas

Emigration

Movement of individuals out of a population

Territoriality

The defense of a bounded physical space against encroachment by other individuals

Demography

Study of key characteristics of populations and how they change over time

Life table

Summarizes the survival and reproductive rates of individuals in specific age groups within a population

Cohort

Group of individuals of the same age, from birth until all of the individuals are dead

Survivorship curve

A plot of the proportion or numbers in a cohort still alive at each age

Exponential population growth

A population that experiences ideal conditions increases in size by a constant proportion at each instant in time.

Intrinsic rate of increase

The per capita rate at which an exponentially growing population increases in size at each instant in time

Carrying capacity

Maximum population size that a particular environment can sustain.

Logistic population growth

The per capita rate of population growth approaches zero as the population size nears the carrying capacity

Life history

Traits that affect an organism’s schedule of reproduction and survival make up this

Semelparity

“One-shot” pattern of big-bang reproduction

Iteroparity

Repeated reproduction

K-Selection

Selection for traits that are advantageous at high densities

R-selection

Selection for traits that maximize reproductive success in uncrowded environments (low density)

Density independent

A birth rate or death rate that does not change with population density

Density dependent

A death rate that increases with population density or a birth rate that falls with rising density

Population dynamics

Population fluctuations from year to year or place to place

Metapopulation

Immigration and emigration are particularly important when a number of local populations are linked

Demographic transition

The movement from high birth and death rates toward low birth and death rates, which tends to accompany industrialization and improved living conditions, is called

Age structure

The relative number of individuals of each age in the population

Ecological footprint

Summarizes the aggregate land and water area required by each person, city, or nation