ther interaction of environmental factors and intrinsic characteristics (life history traits) and their effects on populations
network of distinct populations that interact with one another by exchanging individuals.
source populations continually send out dispersers into poorer habitats
study of population size and age structure through time
number of individuals in each cohort
the percentage of an original population that survives to a given age
type 1; low mortality early in life, high mortality later in life. type 2; hydra; individuals are equally likely to die at any age. type 3; high mortality rate early in life, low mortality later in life.
cost of reproduction
reduction in future reproductive potential resulting from current reproductive effort.
single, large reproducive event, i.e. annual plants, most insects
offspring produced several times over many seasons
models of population growth
Population growth is defined as:
r = (b-d) + (i-e)
Where r = rate of population increase
b = birth rate
d = death rate
i = movement into an area (immigration)
e = movement out of an area (emigration)
maximum number of individuals that an environment can support
as a population increases, reproductive rates decline and/or mortality rates increase
rate of population growth limited by something unrelated to population size. i.e. cold winters, droughts, storms, volcanic eruptions
organisms living together in a location are members of a community
a community is simply an aggregation of species that happen to occur together.
communities are an integrated unit that can function as a "superorganism"
each organism in a community survives in a different way
all the ways an organism uses the resoucres in its environment
competition between two or more species attempt to use the same resource
the entire niche that a species is capable of using
the actual set of environmental conditions in which the species establishes a stable population
if two species are competing for a limited resource, the species that uses the resource more efficiently will eliminate the other
the consuming of one organism by another
bright conspicuous markings of certain distasteful or poisonous animals, which predators recognize and learn to avoid.
a harmless species has evolved to mimic a toxic or noxious species
two harmful species mimic one another
species that have a large effect on the composition of communities
even if there is environmental stability year after year, communities still tend to undergo changes
a disturbance occurs (fire, clearing) and eventually marks of the disturbance disappear
the area begins as bare and lifeless and organisms gradually move into the area
intermediate disturbance hypothesis
communities experiencing moderate amounts of disturbance have higher species richness than those experiencing very little or a lot of disturbance
autotrophs that use light as their energy
use inorganic oxidation reactions
consume other organisms for their energy
one step in a food chain
second trophic level
third trophic level, eat herbivores
fourth trophic level, eat primary carnivores
feed on already dead organisms
what are global patterns influenced by?
the amount of solar radiation the reaches different parts of the earth and seasonal variations.
patterns of global atmospheric circulation and the resulting oceanic circulation
The Earth receives energy at a high rae as visible or near-visible electromagnetic radiation.
hot air rises because molecules move faster with increasing temperature
the coriolis effect
The curvature of the wind paths due to the rotation of the Earth
wet air flowing up a mountain loses moisture, as it descends on the other side it is dry. the ocean side of the mountain range is wet and the landward side is dry.
conditions may also vary greatly on smaller spatial scales. localized sets of climatic conditions are microclimates.
major types of terrestrial ecosystems. characteristic appearance, widespread and defined by regional climatic conditions, vegetation and animals present. temperature and moisture are the two main factors that determine locations.
what are some examples of biomes?
Tropical rain forest, Savanna, Desert, Temperate, grassland **great prairies of the US, Temperate, deciduous forest*Pacific Northwest, Temperate evergreen forest, Taiga, tundra, polar ice, mountain zone, chaparral, warm moist evergreen forest
what is one factor of continental shelves?
they're higher in productivity in nutrients. 99% of food from the ocean comes from continental shelves.
beyond continental shelves but near the surface (receive sunlight). tuna, squid and whales are commonly fished in open ocean.
hydrothermal vent communities
support large communities which depend on chemoautotrophs.
the branch of biology that deals the effects of humans on the environment and the conservation of biological diversity.
when a species is found in one geographi area and nowhere else.
contain some of the fastest growing human populations
depicts age distribution
what factors are responsible for extinction?
humans affect habitat loss in four ways; destruction, pollution, disruption and fragmentation.
changes in microclimate or access by nonnative species.
a natural process by which a species expands its geographic range
change in the properties of groups of organisms over the course of generations.
sea lilies and feather stars
ray finned fishes
lobe finned fishes
sea urchins and sand dollars
mitochondria and chloroplasts were free-living bacteria that were engulfed by the ancestor of eukaryotes and plants.