exam 3 pt 2 (biotic/abiotic -> microclimate)

what 2 factors are responsible for the distribution of species?

→ for instance, why are grizzly bears found in different regions than black bears?

biotic + abiotic factors

biotic

living factors, meaning interactions between organisms/species

→ like predation, herbivory, mutualism, etc.

abiotic

non-living factors

→ like rainfall, temperature, pH of soil, etc.

dispersal

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

__________ contributes to the global distribution of organisms. what organism is globally distributed?

dispersal

→ humans !! we don’t struggle to disperse like animals do

what can limit dispersal?

barriers like species on an island, species on different continents, etc.

animals that can get over dispersal barriers do what instead?

natural range expansion

→ they get to new areas on their own

what do natural range expansions show?

the influence of dispersal on distribution

→ how animals disperse to strengthen their distribution over an area

→ like the cattle egeret !! it’s a bird that originated in africa and naturally expanded its range to north america and all along the south american coast

invasive species/species transplants. what is the effect of invasive species?

species brought into a new area by humans; they did NOT get there on their own

→ they can disrupt communities or ecosystems because they are not native and do not have natural predators, they are better competitors and will literally bulldoze other species in their way

what are some examples of invasive species?

bullfrog, gypsy moth, python

not all organisms will occupy all of their potential range. species distribution may be limited by what kind of behavior?

habitat selection behavior

what is an example of habitat selection behavior

pine snakes live in the pine barrens in nj → they select that habitat because of sandy, loose soil that lets them burrow into the ground which is why you don’t find them in west windsor; the soil is too hard around here

what biotic factors (living interactions) affect the distribution of organisms?

predation + competition + disease + herbivory

what abiotic factors (non-living) affect the distribution of organisms?

temperature + water + sunlight + wind + rocks/soil

→ most abiotic factors vary in space and time, meaning they are not uniform and will change based on the time of day or position of an organism

climate

long-term average of weather conditions

→ typically temperature, water, sunlight, and wind

weather

weather conditions happening at a particular time, in a particular place

macroclimate

consists of patterns on the global, regional, and local level

microclimate

consists of very fine patterns

→ such as those felt by a community of organisms underneath a fallen log