AP Biology - Community Ecology Chapter 54, AP Biology: Animal Behavior, AP Biology: Population Ecology

community

a group of populations of different species living close enough to interact

interspecific interaction

a relationship between individuals of two or more species in a community

interspecific competition

a -/- interaction that occurs when individuals of different species compete for a resource that limits their growth and survival

competitive exclusion

the concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population

ecological niche

the sum of a species' use of the biotic and abiotic resources in its environment

resource partitioning

the differentiation of niches that enables similar species to coexist in a community

predation

a +/- interaction between species in which one species kills and eats the other

cryptic coloration

camouflage such that a potential prey is difficult to spot against its background

aposematic coloration

the bright colors of animals with effective physical or chemical defenses that acts as a warning to predators

Batesian mimicry

a palatable or harmless species mimics an unpalatable or harmful model

Mullerian mimicry

two or more unpalatable species resemble each other

herbivory

a +/- interaction in which an organism eats parts of a plant or alga

symbiosis

a relationship where individuals of two or more species live in direct and intimate contact with one another

parasitism

a +/- symbiotic interaction in which one organism derives its nourishment from another organism which is harmed in the process

parasite

an organism that feeds on the cell contents, tissues, or body fluids of another species while in or on the host organism; often harm but usually do not kill their host

host

the larger participant in a symbiotic relationship, serving as home and food source for the smaller symbiont

mutualism

a +/+ symbiotic interaction that benefits both species

commensalism

a +/0 symbiotic interaction between species that benefits one of the species but neither harms nor helps the other

character displacement

tendency for characteristics to diverge more in sympatric populations than in allopatric populations of two species

disturbance

an event, such as a storm, fire, flood, drought, overgrazing, or human activity, that changes a community by removing organisms from it or by altering resource availability

ecological succesion

Change in an ecosystem that happens when one community replaces another community as a result of changing abiotic or biotic factors.

primary succession

an ecological succession that begins in an area where no biotic community previously existed

secondary succession

succession following a disturbance that destroys a community without destroying the soil

Ethology

study of animal behavior

Behavior

what an animal does and how it does it

Instinct (Innate) Behavior

behaviors that are inherited

Kinesis

random movement of animal in relation to stimulus; the stimulus causes an alteration in rate or direction of activity or movement.

Fixed-action Patterns

sequence of unlearned acts that are unchangeable and usually continue until they are completed

Signal

stimulus that causes change in behavior

Learned Behaviors

Behaviors that are modified based on specific experiences

example: nest building

Associative Learning

ability to connect one stimulus with another

Classical Conditioning

arbitrary stimulus associated with particular outcome

example: training a dog

Operant Conditioning (trial and error)

when faced with two choices, an organism can learn to choose the option with the best reward.

example: students who study to improve their grades

Cognition

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

Social Learning

learning by observing others

Altruism

engaging in behavior that doesn't help you, but helps rest of population (selfless)

Inclusive Fitness

total effect of producing offspring and helping relatives

Foraging

food obtaining behavior

Sexual Selection

seeking and attracting mates/choosing and competing for males

Pheromones

Chemical signals

Imprinting

Some baby bird species will follow the first moving object they see usually the mother.

example: ducks

Migration

organisms move from one place to another periodically, generally in response to temperature or food availability.

example: geese, monarch butterflies

Hibernation

An organism goes dormant for a long period of time to escape cold temperatures

example: bears, chipmunks, frogs

population

A group of individuals that belong to the same species and live in the same area

age structure

Percentage of the population (or number of people of each sex) at each age level in a population.

population density

Number of individuals per unit area

exponential growth

Growth of a population in an ideal, unlimited environment, represented by a J-shaped curve when population size is plotted over time.

carrying capacity

Largest number of individuals of a population that a environment can support

desnsity dependent factor

factor that limits population growth and has greater effect in dense populations than less dense populations

density independent factor

limiting factor that affects all populations in similar ways, regardless of population size

limiting factor

Any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms.

logistic growth

When limiting factors restrict size of population to the carrying capacity of the environment. Forms an S-shaped curve.

k-selected species

Species that produce a few, often fairly large offspring but invest a great deal of time and energy to ensure that most of those offspring reach reproductive age.

r-selected species

Life history traits maximize reproductive success in uncrowded environments. Many small offspring that mature quickly, little if any parental care.

survivorship curve

a graph showing the decline in numbers of a cohort over time

Geographic Range

The area inhabited by a population.

Population Density

For Example: Wildebeest live in densely populated herds.

How individuals in a population are spaced out across the range. Clumped (most common), uniform, random (plants).

Population Distribution

How individuals in a population are spaced out across the range. Clumped (most common), uniform, random (plants).

Growth Rate

This determines whether the size of the population increases, decreases, or stays the same.

Why is Age Structure important?

Determines how many individuals are likely to reproduce in a population.

1) Birth Rate

2) Death Rate

3) Immigration

4) Emigration

4 Factors that Affect Population Growth?

Birth Rate

The rate at which individuals in a population are born.

Death Rate

The rate at which individuals in a population die.

The birth rate must be higher than the death rate.

In order for populations to grow, what has to happen to the birth rate and the death rate?

Immigration

The movement of individuals INTO an area. This can cause a population to grow.

Emigration

The movement of individuals OUT of an area. This can cause a population to decrease in size.

1) Exponential Growth

2) Logistic Growth

The two different types of Population Growth

Exponential Growth

Individuals reproduce at a constant rate. The larger he population, the faster it grows. Not affected by density dependent limiting factors.

Logistic Growth

Population Growth slows or stops following a period of exponential growth. The population has reached carrying capacity and IS affected by density dependent limiting factors.

Limiting Factor

Resource/Something that can cause population growth to decrease; controls the growth of a population.

Carrying Capacity

Limiting Factors determine the _____________ of an environment for a species. (How many individuals the environment can support.)

1) Competition

2) Predation

3) Parasitism and Disease

4) Stress from Overcrowding

5) Unusual Weather

6) Natural Disaster

6 things that can limit population Density (Size).

Density dependent factor definition

A limiting factor that depends on population size.

Density dependent factor examples

1) Competition

2) Predation

3) Parasitism and Disease

4) Stress from overcrowding

competition

Organisms fight for water, space, sunlight, and other resources. Increases as population size increases.

density independent limiting factor definition

Limiting factor that affects ALL populations regardless of size.

Density independent limiting factor examples

1) Weather

2) Natural Disaster

3) Seasons

4) Human Activities