Environmental science chapter 3-4 test

Adaptation

Acquisition of traits that allow a species to survive in its environment.

-Involves changes in a population with characteristics that are passed from one generation to the next.

natural selection

The process of the fittest individuals surviving and passing their traits to the next generation, while others reproduce less successfully.

-Acts on DNA

Mutations

Changes in the genetic material of an individuals, these changes are inherited by offspring.

-If mutations occur in the reproductive (germ) cells they are passed on to offspring

-If mutations occur in the body (somatic) cells they are not passed on to the offspring

-Most have little effect on fitness, and some can have a negative effect, but some happen to be useful in helping individuals exploit new resources or survive more successfully in new environmental conditions.

Critical limiting Factor

A factor that keeps an organism from expanding everywhere (Inappropriate levels of moisture, light, pH, nutrients, competition, predation)

-A organism's physiology and behavior allow it to survive only in certain environments

tolerance limits

Minimum and maximum limits for physical conditions (such as temperature) and concentrations of chemical substances beyond which no members of a particular species can survive.

-A range of tolerance curve identifies where a species will have abundance in relation to an environmental factor

Habitat

describes the place or set of environmental conditions in which a particular organism lives

ecological niche

Both the role played by a species in a biological community and the set of environmental factors that determine its distribution

indicator species

Species that serve as early warnings that a community or ecosystem is being degraded.

Sensitive to the environment and indicate environmental conditions.

Ex: Trout requires cool well-oxygenated water and indicates water quality. Will die in warm, low-oxygen water.

competitive exclusion principle

principle that states that no two species can occupy the same niche in the same habitat for long

-The one that is more efficient is using available resources will exclude the other

resource partitioning

When species divide a niche to avoid competition for resources

Speciation

Formation of new species

Ex: Galapagos Island finches, thought to have originated from South America, were far enough apart that the isolated island populations couldn't interbreed and gradually changed in response to their environments.

allopatric speciation

The formation of new species in populations that are geographically isolated from one another.

sympatric speciation

The formation of new species in populations that live in the same geographic area

Taxonomy

The scientific study of how living things are classified

-Taxonomists classify life into 3 general domains according to cell structure.

intraspecific competition

competition between members of the same species

interspecific competition

competition between members of different species

Batesian mimicry

a harmless species mimics a harmful one

Müllerian mimicry

two or more unpalatable (taste bad) species resemble each other

Exponential (r) growth

population growth with no limits and has a distinctive shaped "J" growth curve when graphed over time

logistic growth

Population growth that is controlled by limited resources. Graphed as an "s" curve

disturbance-adapted species

Species that depend on repeated disturbance for their survival and propagation

Examples of disturbances that helped or harmed communities:

Kingston Plains, Michigan- clear cutting and fires-damaged

Yellowstone National Park-Fires allowed for greater biodiversity

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

climax community

a stable community that no longer goes through major ecological changes

generalists

Have a wide range of conditions or exploit a wide range of resources

Ex: black bears eat meat, berries, grasses, garbage, and found in a large geographical area

Specialists

Have a narrow ecological niche

Ex: giant pandas can only naturally survive in bamboo forests.

Archaea

DNA is not in a nuclear membrane and lives in extreme environments, cell structure is different from bacteria

Eukarya

DNA is contained in nuclear membrane

4 kingdoms of Eukarya

Protists, Plants, Fungi, Animals

Competition

An antagonistic relationship within a biological community

Scavengers, detritivores, decomposers…

Feed on dead things

Are NOT predators

Camouflouge

When a species displays forms, colors and patterns that help them hide

Ex: walking sticks, tigers

symbiosis

a process where two or more species live intimately together with their fates linked

Mutualism

When both species benefit from the relationship

Commensalism

When one species benefit and the other is neither harmed or benefited

Ex: Epiphytes (air plants) will rest on trees, use nutrients from the air around it and rely on rainwater

Parasitism

When one species is benefited and the other is harmed

Ex: ticks and humans

Coevolution

led to close evolutionary relationships between many species

keystone species

Play a critical role in biological community, environment will collapse if they are not there.

Ex: Kelp forests provide habitat for numerous marine species kelp is consumed by sea urchins, but is kept in check by consumption by the sea otter (key stone). If otters are eliminated, the kelp is consumed and the ecosystem collapses.

carrying capacity

The biomass of organisms that an environment can sustain over the long term

-When a population overshoots the carrying capacity of its environment, resources become limited and death rates rises and the population may crash (many die off)

Sometimes predator and prey populations…

oscillate in synchrony with each other (populations will trail high and low together)

Density-dependent factors

Affected by population size

-Larger populations can limit food availability, spread disease, attract predators

Density-independent factors

limits a population that are non-biological and are the result of acts of nature

Ex: drought, early frost, flooding, habitat destruction by people

"r" selected species

-rely on high rates of reproduction and growth to survive

-reach sexual maturity quickly

-have a shorter life span

-have a lot of offspring and provide little care to the offspring

-prey

Ex: insects, parasites, rodents, annual plants

"k" selected species

-less offspring and mature slowly

-reach sexual maturity later

-have a longer life span

-have fewer offspring and provide a greater amount of care for the offspring

-predator

Ex: elephants, humans, horses, primates

Type 1 survivorship curves

Long lived individuals

-Tend to be k-selected species

Ex: humans

Type 2 survivorship curve

Individuals die at a uniform rate

-Have characteristics of both Type 1 and Type 3

Ex: birds

Type 3 survivorship curve

Most die young

-Tend to be r-selected species

Ex: butterflies

Diversity

The number of different species in an area or the number per unit

Abundance

The number of individuals of a particular species (or of a group) in an area

-Communities near the equator tend to have high diversity and often related to low abundance

-Communities near the poles tend to have low diversity but can have high abundance of a few species

Randomly distributed populations

Individuals live wherever resources are available, and chance events allow them to settle

Ex: dandelion seeds, younger spiders on silk threads in the wind