Ecology (DAT)

The study of the interactions between organisms and the environment

ecology

The term environment refers to the ___ and ___

physical surroundings and other organisms

Group of individuals of the same species in the same area

population

Group of populations living in the same area

community

All living organisms and the physical environment they interact with

ecosystem

Physical surrounds where an organism usually lives

habitat

Global ecosystem including all of the planet’s ecosystems and landscapes; atmosphere, hydrosphere, lithosphere

biosphere

All ecosystems are composed of ___ and ___ factors

biotic and abiotic

Living organisms are ___ factors

biotic

Animals, plants, and microorganisms are all examples of ___ factors

biotic

Non-living organisms are ___ factors

abiotic

Climate, water, and the physical environment are all examples of ___ factors

abiotic

The environment an organism occupies + the abiotic and biotic resources it uses to survive + the organisms behaviors/roles in that environment =

niche

Two species ___ (can/cannot) occupy the same niche indefinitely

cannot

Range an organism can live in

fundamental niche

Where an organism actually lives, including factors like predators or food abundance

realized niche

The realized niche is typically ___ (larger/smaller) than the fundamental niche

smaller

The distribution and abundance of organisms

population ecology

Population ecology measures what three factors

size, density, and dispersion

Total number of individuals in a population

size

Total number of individuals per area or volume occupied

density

Pattern or spacing among individuals in a population

dispersion

Maximum growth rate under idea conditions

biotic potential

List the five factors that contribute to biotic potential

number of offspring per reproduction, frequency of reproduction, survivorship of offspring, reproductive lifetime, age of reproductive maturity

Maximum number of individuals that a habitat can sustain

carrying capacity

Elements preventing a population from reaching biotic potential

limiting factors

Limiting factors can be divided into two categories

density dependent factors and density independent factors

Density ___ (independent/dependent) factors increase with the density of the population

dependent

Disease, competition, waste accumulation, and predation are all examples of density ___ (independent/dependent) factors

dependent

Density dependent factors are subject to ___ (positive/negative/feedforward/no) feedback

negative

Density ___ (independent/dependent) factors are not impacted by the density of the population

dependent

Natural disasters and climate are examples of density ___ (independent/dependent) factors

independent

Density independent factors are subject to ___ (positive/negative/feedforward/no) feedback

no

Hypothetical unlimited growth of a population is ___ (exponential/logistic)

exponential

Real growth of a population, affected by limiting factors, is ___ (exponential/logistic)

logistic

In logistic growth, growth rate ___ (increases/decreases) as the population reaches the carrying capacity

decreases

Populations ___ (often/rarely) remain constant in size due to various ecological and biological factors

rarely

Populations cycle in size based on ___ dynamics

predator prey

List the four phases of closed system bacterial growth

lag, exponetial, stationary, death

The phase when bacteria adapt to growth conditions and experience no division

lag phase

The phase when the bacteria population is increasing exponentially and the growth rate is higher than the death rate

exponential

The exponential phase of bacterial growth is often also called the ___ phase

log

The phase when bacterial growth is limited due to certain factors and the growth rate is equal to the death rate

stationary

The phase when the bacteria die off and the death rate is greater than the growth rate

death

The ___ curve shows many individuals typically survive at the different stages of life

suvivorship

Type ___ survivorship curves show most organisms surviving until later ages, then sharply dying off

I

Humans and elephants are examples of type ___ survivorship curves

I

Type ___ survivorship curves show a random length of survivorship all throughout their lifetime

II

Type ___ survivorship curves are negatively linear

II

Birds and rodents are examples of type ___ survivorship curves

II

Type II survivorship curves occur because death occurs due to events that are ___ likely at any point in their life

equally

Type ___ survivorship curves show that most organisms die young and only a few survive to reproductive age

III

Oysters, insects, and fish are all examples of type ___ survivorship curves

III

Type III survivors often live for a ___ (short/long) time

long

List the two major reproductive strategies

K and R

K-selected species have a ___ (high/low) number of offspring

low

K-selected species have ___ (higher/lower) parental care

higher

K-selected species have a ___ (high/low) population growth rate

low

R-selected species have a ___ (high/low) number of offspring

high

R-selected species have ___ (higher/lower) parental care

lower

R-selected species have a ___ (high/low) population growth rate

high

Humans are an example of a ___(K/R)-selected species

K

R-selected species have ___ (longer/shorter) lifespans

shorter

K-selected species have ___ (longer/shorter) lifespans

longer

R-selected species have ___ (stable/unstable) environments

unstable

K-selected species have ___ (stable/unstable) environments

stable

R-selected species reach reproductive maturity ___ (slower/quicker)

slower

R-selected species reach reproductive maturity ___ (slower/quicker)

quicker

R-selected species have ___ (stable/unstable) population sizes

unstable

K-selected species have ___ (stable/unstable) population sizes

stable

R-selected species have ___ (smaller/larger) sized offspring

smaller

K-selected species have ___ (smaller/larger) sized offspring

larger

R-selected species have ___ (higher/lower) mortality rates

higher

R-selected species have ___ (higher/lower) mortality rates

lower

R-selected species typically follow a type ___ survivorship curve

III

K-selected species typically follow a type ___ survivorship curve

I

Measures the number of births per individual in a population over a given time

per capita birth rate

Per capita growth rate reflects how frequently ___ is occurring

reproduction

per capita birth rate (b) =

total births / total population

Overall variety of different organisms in a community

species diversity

List the two components of species diversity

richness and relative abundance

The total number of different species present in a biological community

species richness

The proportional abundance of different species in a community

relative abundance

Species richness is ___ related to a community’s geographic size

directly

The larger the geographic area, the ___ (smaller/larger) the number of species

larger

The more balanced the relative abundance is, the more ___ (stable/unstable) the species diversity is

stable

To maxmize species diversity, you want a ___ (high/low) species richness and a ___ (high/low) relative abundance

high, high

Examines how interactions between species affect community organization

community ecology

Competition for resources between different species

interspecific competition

Competition for resources between individuals of the same species

intraspecific competition

Two species competing for the same limited resources cannot coexist indefinitely in the same niche

competitive exclusion principle

Two species in the same niche but use slightly different resources or secure resources in a different way

resource partitioning

The tendency for traits to become more divergent due to competition in the same environment

character displacement

Reduction in competition due to divergence of features

character displacement

Aggression directly between individuals

interference competition

Occurs indirectly through depletion of a common resource

exploitation competition

Occurs between two species when they are preyed upon by the same predator

apparent competition

___ competition occurs when one population is reduced

exploitation

___ competition occurs when two species indirectly compete for survival

apparent

Broad term for any (+/-) interaction

exploitation