Exam 3 Flashcards
(99 cards)
what is a habitat?
an area with the combination of resources and environmental conditions where individuals of a given species settle, survive, and reproduce. habitats are distinguished by physical features, such as dominant plant type.
what is a niche?
the range of abiotic and biotic conditions an organism can tolerate. function and position of a species in the environment (includes all of its abiotic and biotic interactions)
can two species have the same niche?
no because each species has unique phenotypes that determine the conditions it can tolerate.
what is n-dimensional hypervolume?
sum of all the environmental factors acting on a species
what is a fundamental niche?
the range of abiotic conditions (temp, humidity, salinity) where a species can persist.
what is a realized niche?
the range of abiotic and biotic conditions where a species can persist (biotic interactions-competition, predation, and pathogens- may prevent a population from persisting in an area.
what is the geographic range?
total area inhabited by a population (temperature and drought define the geographic range of sugar maple)
variation in the environment can result in geographic ranges that are composed of disjunct _________ ________
habitat patches
(the geographic range of Fremont’s leather flower is 3 counties in Missouri where those plants are restricted to areas of dry, rocky soils on limestone outcroppings (glades).
what is scale?
plants further restricted by variation in soil structure and quality of glades
species distribution modeling, species habitat modeling, and climate envelope modeling all mean ___________ _____________ _________________
ecological niche modeling
ecological niche modeling can predict future _________ ____________ from limited information along with range _______________ and potential for ___________
species distribution
expansions
invasions
_________ changes can cause a shift in the geographic range of species
temperature
provide an example of how global warming can expand species’ range
average temps in the North Sea have increased 2 degrees C from 1977-2003, causing southern fish species to expand their ranges north. fish species richness in the North Sea has increased steadily over this time and is positively correlated with ocean temperature (due to increased energy production in warmer waters)
provide an example of emerging threats in thermoregulation
White nose syndrome in bats: WNS is a fungal infection that covers the muzzle of the bat and disrupts bats’ torpor (short term hibernation when they lower their metabolism) by waking them up during their torpor which causes them to starve to death. 11 species of North American bats are susceptible and more than 6 million bat deaths since 2006 when it was introduced.
what are the 5 important population distribution characteristics?
- geographic range
- abundance
- density
- dispersion
- dispersal
what is the definition of population?
all the members of a species in a given area at a given time (unit of evolution through natural selection)
research approach: variation in number, density, demographic, composition of individuals
individuals ________, populations __________
adapt, evolve
all populations must deal with what similar challenges?
- competition (limited resources, mates, and habitable space)
- predation
the absolute number of individuals is ____________
abundance (N)
the abundance per unit area is ___________
density (D)
-population dispersion-
__________ is when individuals are aggregated in discrete groups (social groups or clustering around resources)
clustered
________ ________ is when each individual maintains a uniform distance between itself and its neighbors (defended territories, croplands)
evenly spaced
_________ is when the position of each individual is independent of other individuals, not common due to non-random environmental heterogeneity.
random
what is the Baas Becking Hypothesis?
everything (every gene) is everywhere but the environment selects