173 terms

DAT Bootcamp - Ecology

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a _____ is a group of organisms, which can interbreed and make viable, fertile offspring
species
a species is a group of organisms, which can interbreed and make _____, _____ offspring
viable; fertile
to be considered a species, offspring must have the capacity to _____
reproduce
a _____ is a type of place an organism lives
habitat
habitats include all other organisms, as well as the _____ and _____ aspects of the environment
physical; chemical
a _____ is a group of organisms of a specific species, which live in 1 location
population
what does an ecological community encompass?
all populations living in a certain area, where different species interact with each other
an _____ is an ecological community (biotic), plus the abiotic factors the populations interact with
ecosystem
_____ factors are the nonliving elements in an ecosystem; such as, temperature, sunlight, or water levels
abiotic
_____ factors are the living elements in an ecosystem; such as, plants, animals, or microoragnisms
biotic
density dependent factors become more significant as the population density (increases/decreases)
increases
diseases and resource competition are examples of density _____ factors
dependent
density _____ factors exert their effects, regardless of the population density
independent
weather and climate are examples of density _____ factors
independent
the biosphere is a combination of all the _____ on Earth
ecosystems
the _____ encompasses interactions between ecosystems, as well as between the lithosphere, geosphere, hydrosphere, and atmosphere
biosphere
what is an organism's niche?
all the biotic and abiotic resources it uses
what is an organism's realized niche?
the environment where it truly lives
the _____ refers to the full range of environmental conditions an organism could theoretically survive
fundamental niche
in reality, which type of niche are organisms restricted to - why?
the realized niche - competition between species
Gause's law is also known as the _____ principle
competitive exclusion
the _____ states that 2 species are not able to occupy the same niche while also maintaining their population levels
competitive exclusion principle (Gause's law)
_____ allows 2 species to coexist, despite the fact that they seem to compete for resources
resource partitioning
resource partitioning occurs when species use different means to obtain the _____ resource, or they seek out _____ resources
same; slightly different
resource partitioning occurs when species occupy subtly different _____
niches
how might niche overlap/potential competition be minimized?
chance genetic mutations that allow for the pursuit of different resources (compared to a similar species)
describe the mechanism of character displacement:
niche overlap --> chance genetic mutations --> pursuit of different resources --> populations with different characteristics and niches
what is a common example of character displacement?
the beak variations of Galapagos finches, which allows them to eat different types of seeds
in _____, a population evolves into more than 1 distinct species
speciation
_____ speciation refers to a speciation event that occurs as a result of naturally-occurring evolution
natural
artificial speciation is a result of artificial, intentional methods such as _____
selective breeding
what are the 2 types of biological interactions, as they relate to time?
short-term; long term
competition is a type of _____ biological interaction, where 2 species compete for the same resources
short-term
what are the 3 types of competition?
exploitation; intraspecific; apparent

(competition is a short-term biological interaction)
exploitation competition is _____, and it occurs when a common resource is _____
indirect; depleted
_____ competition occurs between members of the same species
intraspecific
apparent competition occurs when _____ predator preys on _____ species
1; 2
_____ is a close, long-term biological interaction between 2 organisms living in the same environment
symbiosis

(symbiosis = "living together")
what are 3 types of ecological symbiosis?
mutualism; commensalism; parasitism
_____ occurs when organisms benefit from the each-other's presence
mutualism
describe the process of commensalism:
1 organism benefits and the other is neither helped nor harmed
_____ occurs when 1 organism benefits at the other's expense
parasitism
what is a food chain?
linear depiction of what eats what
a _____ depicts the interconnections between food chains within a community
food web

(expanded version of a food chain)
_____ refers to an organism's position within a food chain/web
trophic level
autotrophs produce energy (_____ substances) from environmental, _____ substances
organic; inorganic
heterotrophs must ingest _____ compounds to generate energy and survive
organic
_____ is the relationship between a predator and prey
predation
primary producers are located at the _____ trophic level
lowest
primary producers are usually _____
autotrophs
primary producer/autotrophs tend to undergo _____ to produce the _____ of an ecosystem
photosynthesis; biomass
what is biomass?
the total mass of living organisms in an area or ecosystem
what is a primary consumer?
an organism that solely consumes primary producers
primary consumers are located 1 trophic level higher than _____
primary producers
primary consumers tend to be _____
herbivores
what is a herbivore?
an organisms that derives its energy from plant matter
_____ consumers prey on primary consumers
secondary
secondary consumers are located _____ higher than primary consumers
1 trophic level
secondary consumers are also known as primary _____
carnivores
what is a carnivore?
a meat/animal tissue eater
what is an omnivore?
an organism that consumes both plant and animal material
_____ eat secondary consumers; hence, they are located 1 trophic level higher than them
tertiary consumers
what is an apex predator?
the predator at the top of the food chain
do any other organisms prey on the apex predator?
no
does a food chain/web need to extend beyond a tertiary consumer?
no - the apex predator could theoretically be a secondary consumer just as easily as it could be a quaternary consumer
what percentage of energy is lost when moving from a lower to higher trophic level?
about 90%

(higher trophic levels have about 10% the energy of lower trophic levels)
the most biomass is stored at the _____ trophic levels, while the least biomass is stored at the _____ trophic levels
lowest; highest
scavenging is done by both _____ and _____
carnivores; herbivores
_____ are animals that decompose other dead animals
scavengers (ex: vultures, beetles)
_____ are plants, fungi, and microorganisms that consume dead organic material for survival
saprophytes
in general, _____ survive by breaking down dead/decaying organic matter
decomposers
what is the most important decomposer in many ecosystems?
fungi (bacteria are also important)
what results when decomposers break-down dead/decaying organic matter?
detritus
what is detritus?
a combination of feces and decomposing organic matter
_____ consume detritus (organic wastes)
detritivores (subclass of decomposers)
worms and slugs are examples of _____
detritivores
_____ is a species' ability to undergo its highest possible birth rate and lowest possible death rate, resulting in a maximal population growth
biotic potential
biotic potential occurs when environmental conditions are _____ for that species
ideal
what is carrying capacity?
the maximum population size that an ecosystem can sustain
_____ species undergo long gestation periods to produce few, large offspring that take a relatively long time to mature
K-selected
_____ species provide significant parental investment and support
K-selected
in K-selected species, a high percentage of offspring survive to _____
reproductive age
K-selected species show a _____ survivorship curve
type I
describe type I survivorship curves:
high rate of survival during early and middle age, with mortality increasing during old age
_____ species produce abundant, small offspring that mature quickly
R-selected
_____ species provide little to no parental investment/support
R-selected
a high percentage of offspring _____ to reproductive age in R-selected species
do not survive
R-selected species show a _____ survivorship curve
type III
describe type III survivorship curves:
survival undergoes exponential decay with respect to age
describe type II survivorship curves:
the probability of survival remains relatively constant regardless of the organism's age
a _____ species is the first species to inhabit a barren area and begin ecological succession
pioneer
what is ecological secession?
ecological community development (or change) over time
what are the 2 types of ecological succession?
primary; secondary
_____ succession happens after a large disturbance, or on substrates that have never supported life before
primary
primary succession begins with the establishment of a _____ species because it occurs in areas that have never supported life
pioneer
climax communities have reached _____, meaning there is a balance in the prevalence of each species
a steady state of ecological succession
secondary succession follows _____ disturbances than primary succession, and it occurs on a terrain that has _____ supported life
smaller; already
secondary succession begins with the establishment of grasses and shrubs - why?
the terrain previously supported life and soil is already present
what does a keystone species do?
maintain ecological balance despite a relatively low abundance
_____ maintain ecological balance by hunting other species to prevent their overabundance
keystone predators
a _____ is a large area of land/water, defined by biotic factors that are adapted to the climate and geography of that region
biome
what abiotic factors have the most important effect on biome distribution?
rainfall and temperature
areas with similar latitudes can have radically different biomes, even though they receive about the same amount of sunlight - what is the significance of this?
its gives proof that rainfall/temperature are the most important abiotic factors for biome distribution
tropical rainforest climate:
consistent hot temperature and heavy rainfall
tropical rainforest characteristic plants:
tall trees with most branches near the top, vines, ferns, orchids
tropical rainforest characteristic animals:
reptiles, amphibians, insects, small and large mammals, colorful birds
which biome has the greatest amount of diversity?
tropical rainforest
tropical rainforest example:
Amazon rainforest
savannas climate:
high temperatures, small amount of rainfall (seasonal)
savannas characteristic plants:
grasses, scattered trees
savannas characteristic animals:
ungulates (large, hooved, plant-eating mammals)
_____ have grasslands with diffuse trees
savannas
_____ experience seasonal drought and fires
savannas
savannas example:
African safari
temperate grasslands climate:
cool winters; hot summers; seasonal rain (less rain than savannas)
temperate grasslands characteristic plants:
grasses; small shrubs
temperate grasslands characteristic animals:
large, grazing mammals; birds; reptiles
like savannas, _____ also experience seasonal droughts and fires - but they also have fertile soils
temperate grasslands
temperate grasslands example:
North American prairie
temperate deciduous forest climate:
warm summer, cold winter; moderate precipitation; snows during winter
temperate deciduous forest characteristic plants:
hardwood deciduous trees, ferns, mosses, wildflowers
temperate deciduous forest characteristic animals:
rodents, birds, squirrels, deer, bears, porcupines
in a _____, trees shed their leaves in the winter due to poor growing conditions
temperate deciduous forest
temperate deciduous forest example:
eastern North America
chaparral climate:
mild winters, hot dry summers
chaparral characteristic plants:
trees, shrubs, poison oak, cacti
chaparral characteristic animals:
foxes, jackrabbits, deer
a _____ has scattered vegetation, often with small tough leaves to conserve water
chaparral
chaparrals are unlike savannas and temperate grasslands because they experience _____ droughts and fires
common
chaparral examples:
California's west coast; Mediterranean coast
desert climate:
hot days, cold nights; extreme temperature fluctuation; vary little rain
desert characteristic plants:
cacti
plant growth occurs after rainfall in a _____
desert
desert plants have leathery leaves or spines to conserve _____
water
desert characteristic animals:
rodents, reptiles, arachnids, coyotes, bobcats
_____ have animals that are often nocturnal and conserve water by not producing urine (or producing concentrated urine)
deserts
desert example:
Arizona
taiga climate:
cold winters with snowfall; warm, rainy summers
taiga characteristic plants:
coniferous trees
taiga characteristic animals:
bears, otters, wolves, rabbits owls
what is the largest terrestrial biome?
taiga
most of Canada and Alaska is a _____
taiga
tundra climate:
cold; very little precipitation
tundra characteristic plants:
mosses, grasses, lichens, shrubs
tundra characteristic animals:
bears, caribou, wolves, foxes, rodents
the ground freezes during _____ winters
tundra
in a _____, the topsoil thaws during the summer - but the deeper soil stays frozen
tundra
tundra example:
Iceland; Northern Canada
polar climate:
cold; precipitation is snow
polar characteristic plants:
no plants
polar characteristic animals:
polar bears and penguins
_____ biomes are ice-covered for most of the year
polar
Antartica is an example of a _____ biome
polar
_____ biomes cover around 75% of the Earth, and are therefore the largest of Earth biomes
aquatic
what contributes to most of the Earth's atmospheric oxygen?
photosynthetic algae that live in aquatic biomes
what are the 2 key classes of aquatic biomes?
saltwater and freshwater
freshwater biomes have a salt content is less than _____
0.1%
_____ biomes account for only 3-4% of all aquatic biomes
freshwater
what is an estuary?
where freshwater from a coast (river/stream) meets a saltwater ocean
the _____ is where ocean meets land
intertidal zone
the intertidal zone is _____ water at low tide and _____ water at high tide
above; below
the intertidal zone is above water at _____ tide and below water at _____ tide
low; high
layers of the ocean are categorized based on the amount of _____ they receive
sunlight
what are the layers of the ocean, from superficial to most deep?
euphotic; disphotic; aphotic
the _____ zone is closest to the ocean surface
euphotic
plants are able to survive and undergo _____ in the euphotic zone
photosynthesis
what part of the euphotic zone allows sunlight to penetrate all the way down to the floor of the ocean?
littoral zone
the _____ zone lies below the euphotic zone
disphotic
the _____ zone is semi-irradiated with sunlight (not sufficient for the survival of most plants)
disphotic
the aphotic zone is found between the _____ zone and the _____
disphotic; ocean floor
almost no light penetrates the _____ of the ocean
aphotic zone
bioluminescent species are found in which two ocean zones?
disphotic and aphotic
how do fish survive in the aphotic zone?
they feed on dead matter that sinks to the floor