ecology Flashcards
biotic
living
abiotic
non-living
community
a group of multiple different species interacting with one another
ecosystem
a group of species interacting both with each other and their environment
organismal ecology
the study of how an organism’s structure, physiology, and behavior meet environmental challenges
-how well is an organism suited to
its environment?
-what traits help it thrive?
population ecology
the study of a population of the same species in the same geographic location; focuses on factors affecting how many individuals of a species live in an area
-how many?
-territory?
-why?
community ecology
examines how interactions among species affect community structure and organization
-roles?
-interrelationships?
-mutualism?
-predator/prey?
ecosystem ecology
emphasizes energy flow and chemical cycling among the various biotic and abiotic components of an ecosystem
-energy flow
-origin of energy
-transfer of energy
landscape ecology
the study of interconnected ecosystems across a land area; focuses on the factors that generate patterns of ecosystems in a geographical region
-how are ecosystems
similar/different?
-how are they related?
global (macro) ecology
the broadest field of ecology that looks at how ecosystems are connected across long distances
climate
long term prevailing weather conditions in a particular place over many years
-temperature
-precipitation
-sunlight
-wind/gyres
Hadley cell
-an atmospheric cell ranging from from the equator to 30° north or 30° south that drives a specific pattern of climate in that area
-low-lying air is principally moving
towards the equator
-Coriolis deflection to the west
Ferrel cell
-north of the Hadley cell
-low-lying air is principally moving
away from the equator
-Coriolis deflection to the east
Polar cell
-north of the Ferrel cell
-low-lying air is principally moving
towards the equator
-Coriolis deflection to the west
Coriolis effect (deflection)
the phenomenon generated by the rotation of the earth that the speed of rotation differs at different latitudes
seasonality
differential heating caused by the earth’s tilt that is reflected in seasons
gyre (current)
pattern of water movement in large bodies of water
microclimate
local atmospheric zone in which the climate differs from the surrounding area
subnivium
a microclimate located beneath the snow in northern climates
what modulates climate?
1) seasonality
2) mass specific heating
3) topology
4) microclimate
5) climate change
ecology
the study of the interactions between organisms and the environment
how does latitudinal variation in sunlight intensity lead to predictable latitudinal variation in sunlight and temperature?
the curvature of the earth causes the angle of sunlight to vary depending on latitude
how does latitudinal variation in sunlight intensity lead to predictable latitudinal variation in precipitation?
Hadley cells, Ferrel cells, and Polar cells cause increased precipitation at the equator and at 60° north and south and decreased precipitation at 30° and 90° north and south
how does latitudinal variation in sunlight intensity lead to latitudinal variation in wind?
-increased wind speeds closer to the equator due to increased rotation speed
-Coriolis effect (deflection)
-polar easterlies~ polar cells
-westerlies~ ferrel cells
-NE trade winds~ hadley cells
bodies of water
-gyres
-regulate temperature of surrounding
land
~mass specific heat of water is 4x
greater than soils
windward side of a mountain
meets an air current causing a rain-out event; tends to be wetter than the leeward side
leeward side of a mountain
cool, dry air flows over after moisture is rained out over windward side; tends to be drier than the windward side
climate change
-warming of the earth exacerbated by
human industrialization
-temporally variable: effects vary
across seasons
phenotypic mismatch
evolved traits that were once advantageous but became maladaptive due to changes in the environment
phenological mismatch
when the timing of regularly repeated phases in a species life cycle are no longer advantageous, but maladaptive
phenology
the study of cyclic and seasonal natural phenomena, especially in relation to climate and plant and animal life
no-analog community
a collection of species that have not evolved in an environment in which they are forced to interact due to changes in their range distribution
phenological synchronization
the coordinated timing of biological events
biome
a region of distinctive plant and animal groups well-adapted to the physical environment
of its distributional area
climograph
graphical representation of basic climatic parameters such as average temperature and precipitation at a certain location
ecotone
the overlapping conditions of two or more biomes
tension zone
an ecotone in Wisconsin identified in the late 1950s
net primary production (NPP)
gross primary productivity, or
organic carbon generated by
autotrophs, minus plant respiration;
measured in units of mass per area
per time
primary production
the production of organic
compounds from atmospheric or
aquatic carbon dioxide by autotrophs
biodiversity
-variation of the living world, ranging
from genetic variability within a
species to the diversity of different
ecosystems or biomes on earth
-species richness: number of species
tropical rainforest
a biome characterized by high rainfall, warm temperatures, high
biodiversity, and high NPP
desert
a biome characterized by dry conditions, warm temperatures, high biodiversity, and low NPP
savanna
a biome characterized by seasonal rainfall, recurrent fires, medium biodiversity, and medium NPP
grassland
a biome characterized by strong seasonality in temperature and precipitation, moderate biodiversity, and moderate NPP
chapparal
a small biome characterized by seasonality dictated by oceanic gyres, summer fire regimes, low biodiversity, and high NPP
northern coniferous (boreal) forest
a biome characterized by evergreen trees, long cold winters, short cool summers, high NPP, and low biodiversity
temperate deciduous forest
a biome characterized by overall warm and wet conditions, high
biodiversity, and high NPP
tundra
a biome characterized by cool temperatures, minimal precipitation, low biodiversity, and low NPP
anthrome
-biome created by humans
-similar no matter where you are
-human heat island: increased
temperatures due to an increase of
absorption of solar radiation by
human infrastructure
marine biome
a subclass of aquatic biomes characterized by salt water
freshwater biome
a subclass of aquatic biomes characterized by salt content less than 1% NaCl
pelagic biome
a marine biome characterized by high gross primary productivity, but low net primary productivity scaled for space and time
abyssal zone (hydrothermal vents)
a diverse biome found at the bottom of oceans whose primary producers are chemosynthetic bacteria
coral reef
a shallow marine biome characterized by structures made of calcium carbonate; high biodiversity and high NPP
kelp forest
a shallow marine biome characterized by tree-like plants that house many species and generate high NPP
estuary
a biome located where freshwater and marine systems meet; characterized by high levels of NPP and low levels of biodiversity
salt marsh
a biome located at the intersection of terrestrial and marine biomes found at mid to high latitudes; high NPP, low biodiversity
mangrove forest
a biome located at the intersection of terrestrial and marine biomes
characterized by mangroves, shrub-like trees that provide physical protection for the shoreline; high NPP, low biodiversity
lentic
still, terrestrial freshwater including lakes and wetlands
lotic
moving, terrestrial freshwater such as rivers and streams
olgiotrophic
a cold, deep lake characterized by low NPP and low biodiversity
eutrophic
a warm, shallow lake characterized by high NPP and high biodiversity
eutrophication
the process of making an oligotrophic lake warmer and more nutrient-rich so that its NPP rises
wetland
a lentic, freshwater aquatic biome in which the land is covered by water for part of the year so that the soil is wet, and the vegetation is made up of hydrophytes (water-lovers); includes marshes, swamps, bogs, and vernal pools
river continuum
the observed phenomenon in which the diversity and productivity of a river looks different at different points along its length
coarse particulate organic matter (CPOM)
organic matter that enters a river and is used as the primary energy source for shredders and other organisms within the river
fine particulate organic matter (FPOM)
fine organic particles that are a byproduct of shredders utilizing CPOM
latitudinal diversity gradient (LDG)
the well-documented ecological phenomenon in many taxa that biodiversity is higher near the equator and lower near the poles
mid-domain effect
a statistical model of the LDG in which simply by chance there is more diversity near the equator, at the center of the globe, because all species have finite distributional ranges
causation
what are the stimuli that elicit the response, and what physiological mechanism mediates the response?
ontogeny
how does the behavior change with age, and what early experiences are necessary for the animal to display the behavior? learned or innate?
function
how does the behavior affect the animal’s chance of survival and reproduction? why does the animal respond that way instead of some other way?
phylogeny (behavioral ecology)
how does the behavior compare with similar behavior in related species, and how might it have begun through the process of evolution
proximate (immediate) causes of behavior
causation and ontogeny
fixed action pattern (FAP)
innate behavioral sequence that is invisible and runs to completion; invariant and in response to an external stimulus, a sign stimulus
brood parasitism/”code-breaking”
when birds lay their eggs in the nests of other birds species, exploiting the FAP of that species to feed and raise their offspring
movement taxis
innate movement in response to a directional stimulus or gradient of stimulus intensity
movement kinesis
innate movement in response to a non-directional stimulus
orthokinesis
the speed of movement is dependent upon the intensity of the stimulus
-non-directional
-in presence of risk
klinokinesis
sinousity (linearity) of movement is proportional to stimulus intensity
signal
a stimulus transmitted from one animal to another
communication
transmission and reception of signals
imprinting
any phase-sensitive learning that is rapid and independent of the consequences of the behavior
spatial learning
the intake and memory of the spatial distribution of important landmarks
path integration/ded reckoning
a type of spatial learning in which the organism can compute its location in space based on its past trajectory
cognitive map
internal representation of the landscape; allows an animal to “visualize” a direct and efficient pathway between 2 points in a mapped area, even if it hasn’t previously used that pathway
associative learning
the association of one stimulus to another
cognition
the process of knowing that involves awareness, reasoning, recollection, and judgement
social learning
in social species, the learning of behaviors
foraging ecology
the study of the suite of behaviors an animal employs to search for, find, capture, subdue, and consume food
optimal foraging theory
the theory that organisms balance the cost and benefits of their resources to make decisions about how and when to get food
profitability (optimal foraging level)
profitability = energy in food / (searching time + handling time)
infanticide
the killing of young offspring by a mature animal of its own species
non-consumptive effects
effects not directly resulting from the death of animals by predation
ex) changes in animal behavior in
response to a risk of predation
consumptive effects
effects of predation
ex) population size shrinkage
risk landscape (landscape of fear)
the phenomenon in which prey animals change their foraging behaviors based on an assessment of where in their landscape holds the highest risk of predation
ghost of predators past
the hypothesis that species subject to past selection for antipredator behavior will retain that antipredator behavior, if it is not too costly to do so, even after the predator has disappeared
behaviors/adaptations prey have to avoid being found (search time)
-camouflage
-timing, location of activity
-clumped distribution to flood the
predator
behaviors/adaptations prey have to avoid capture (handling time)
-run or swim away
-taste bad
-protective surfaces such as shells or
hard exoskeletons
type 1 predator functional response
kill rate directly proportional to prey density
type 2 predator functional response
kill rate limited at high prey densities by handling time
type 3 predator functional response
kill rate limited at low prey densities by search time, accelerated at moderate prey densities, and slowed at high prey densities by handling time
reproductive ecology
the study of mating behaviors in animals
monogamy
-animal mating system in which each
male and female mate with one
partner of the opposite sex
-monogamous systems differ in the
length of the monogamous
partnerships
-equal parental investment
polygyny
-mating system in which one male
mates with many females
-female investment > male
investment
polyandry
-mating system in which each female
mates with many males
-male investment > female
investment
promiscuity
-mating system in which males and
females both freely mate with
multiple partners
-female investment > male
investment
anisogamy
the idea that female gametes require a higher energy investment than male gametes
bateman’s principle
the theory that there is greater variance in male reproductive success than in female reproductive success due to females being the more selective sex
resource defense polygyny
one male can mate with many females by overseeing a resource-rich habitat in which the females choose to reside
mate-guarded polygyny
-one male can mate with many
females by actively guarding a group
of females
-the males in these species often
exhibit some exaggerated
secondary sexual characteristics
-found in systems in which the
resources are not defensible
lek polygyny
-males compete for the opportunity
to mate with females by performing
some show of attractiveness
-found in systems in which the resources are not defensible
cooperative polyandry
several males defend a female’s territory
resource defense polyandry
females defend territories that contain smaller areas of groups of males
endler’s guppies
-guppies with no predators~ colorful
spots
-guppies with predators~ no colorful
spots
-colorful spots selected for sexually
and selected against with predators
present
defining populations
1) spatially (almost always a
prerequisite for the other two)
2) genetically (population geneticist’s
emphasis)
3) demographically (birth rate, death
rate, sex and age ratios)
dispersion
spatial organization of a population; can be clumped, uniform, or random
poisson distribution
the statistical phenomenon in which the mean equals the variance
uniform dispersion
-individual organisms are evenly
distributed throughout the
landscape
-population mean is greater than population variance
clumped dispersion
-individual organisms are aggregated
in small groups across the landscape
-population variance is greater than
population mean
random dispersion
-individual organisms are scattered in
no identifiable pattern
-population variance equals
population mean
population characteristics
-demography
-genetic
-abundance/density
-dispersion
density
-individuals per area
-D = n/2wL
~n= total number observed
~L= length of transect
~w= effective half-width of transect
calculating organismal density from nest density
D= D(N)/prt
-p= proportion of nest builders
-r= rate of nest building
-t= nest decay rate
mark-recapture equation
N= mc/r
-N= population size
-m= the # marked in t1
-c= the total number captured in t2
-r= the # marked in t1 and
recaptured in t2
to calculate variance
1) take the count from one quadrant
2) subtract the mean
3) square the total
4) repeat for every quadrant
to calculate mean
1) sum the counts from each
quadrant
2) divide by the number of quadrants
assumptions of the lincoln-peterson (mark-recapture technique) estimator
1) marked and unmarked have equal probability of capture
2) complete mixture after release
3) closed population
exponential growth equation (continuous)
dN/dt= rN
-N= population at time t
-r= difference of per captia birth
and death rates
~r > 0: population increasing
~r < 0: population decreasing
~r = 0: population stationary
exponential growth equation (discrete)
N(t+1)= N(t)(lambda)
-lambda= BxIxDxE (N(t+1)/N(t))
~lambda < 1: population
increasing
~0 < lambda < 1: population
decreasing
~ lambda = 1: population
stationary
r
-intrinsic rate of increase
-inflow - outflow
-used in the continuous differential
equation formulation
- = ln(lambda)
lambda
-finite rate of increase
-factor by which the population is
multiplied per discrete time unit
-used in discrete population
projections
- = e^r
assumptions of exponential growth
1) no immigration or emigration
2) constant b and d
-across time (every year the same)
-across individuals (no age/sex
structure, no individuality)
3) no time lags- population responds
instantly to changing N
negative density dependence
decline in population growth with increasing population size because of reduced survival and reproduction due to:
-competition for resources
-predation
-physiological (intrinsic) factors
-territoriality
-disease
logistic growth (density dependence)
dN/dt= rN((K-N)/K)
allee effect (positive density dependence)
-population growth rates low when
population size is small (low
reproductive success or survival)
-usually associated with disruption of
social or mating system, avoiding
predation, or food acquisition, due to
impacts of low number of individuals
-(causes little dip at beginning of
graph)
stochasticity
random and unpredictable events or changes that can lead to uncertainty and alter populations
environmental stochasticity
random changes to the environment that vary from year to year
catastrophic events
sudden, acute, and intense changes that have a dramatic impact on many individuals in a population
demographic stochasiticity
natural and unpredictable fluctuations in demographics such as the birth rate, death rate, or sex ratio of a population
factors influencing demographic stochasticity
1) patterns of mortality
2) sex ratios
3) patterns of natality
4) age-sex structure
genetic stochasticity
unpredictable changes in the genetic composition of a population
deterministic model
the outcome is determined only by the inputs, and nothing is left to chance or incorporates uncertainty or changing conditions
stochastic model
includes less predictable (weather, food, supplies, etc.) changes and uncertainty around growth rates that alter population factors
type 3 survivorship curve
-mortality rates high early in life
-those who do make it to adulthood
have a long lifespan
type 2 survivorship curve
constant proportion of individuals dying over time, regardless of age
type 1 survivorship curve
-very few individuals die at a young
age
-nonlinear monotonic decline in
survivorship~ once individuals reach
some maximum lifespan, there is a
sharp drop in survivorship at that
point
primary sex ratio
the sex ratio at conception
secondary sex ratio
the sex ratio at birth
tertiary sex ratio
the sex ratio of adults in a population
natality
rate that females are reproducing in a population
dispersal
the permanent movement away from an existing population or from the parent organism
migration
the seasonal movement from breeding to wintering grounds and back again
metapopulation
an assemblage of local populations connected by dispersal
local population
a set group of individuals with a high probability of interacting
matrix
the space between subpopulations in a metapopulation in which the organisms in the population do not live
classic metapopulation
-subpopulations are demographically
independent~ independent b, d, i, e
-dispersal increases viability/resilience~ can “save” each other
source-sink dynamics
-metapopulation with one source subpopulation that provides an excess of individuals, due to a high birth rate, to sink subpopulations with low birth rates
-source: b >d and i < e
-sinks: b < d and i > e
patchy populations
metapopulation in which the dispersal is so high that demographical outcomes are no longer independent
island populations
set of subpopulations within a metapopulation with very low dispersal and therefore very independent demographics
island biogeography equilibrium theory
the number of species on an island reflects a balance between the rate at which new species colonize and the rate at which populations of established species become extinct
island size
-species area curve~ more area, more
species
-small islands have higher extinction
rates
-large islands have lower extinction
rates
island proximity
-islands closer to the mainland have
higher rates of colonization
-islands farther from the mainland
have lower rates of colonization
interspecific interactions
interactions between different species
commensalism
interspecific interaction that is good for one species and has no effect on the other
amensalism
interspecific interaction that is bad for one species but has no reciprocal cost to the other species
competition
interspecific interaction that is bad for both species
exploitation competition
two species use the same resource so they indirectly compete with each other by both using that resource
interference competition
competition between two species that involves direct behavior interaction as one species attempts to keep the other from gaining access to some shared and depletable resource
interspecific killing
-if two species are in competition for
a resource, they will kill members of
the other species to reduce
competition
-occurs most often when there is
both a moderate resource overlap
and moderate risk (moderate
difference in body size)
gause’s competitive exclusion principle
if two species have almost completely overlapping niches, they cannot continue to coexist- one of the two will be driven to extinction
niche
all the combinations of biotic and abiotic resources that an organism can use to survive
fundamental niche
niche occupancy in the absence of competitors
realized niche
niche occupancy in the presence of competitors
niche separation
given some competition, species should be under selection by evolving niches with lower overlap
character displacement
displacement away from an organism’s fundamental niche as a result of competitive pressure; heritable process passed down through generations
character release
the release of an organism from competitive pressure that has pushed it into a realized niche
phenotypic plasticity
-phenotypic change due to
environmental factors
-not heritable through generations
predation
interspecific interaction that is good for one species and bad for the other
herbivory
the consumption of plants
monophagy
eating one thing
polyphagy
eating many different types of food
insect parasitoid
insects that lay eggs on or near a host that is consumed by the larvae
heterospecific predation
predation of another species
crypticity
camouflage
aposematism
organisms with dangerous defense mechanisms are colorful as a warning to predators
batesian mimicry
the phenomenon in which a harmless species has a physical appearance that imitates the warning signals of a harmful species to deter a shared predator
mullerian mimicry
the phenomenon in which multiple species with a shared predator have similar coloration so that the anti-predation effect is multiplied
keystone predator
a predator that is essential to holding together the structure of an ecological community
ecological release
the increase in the population of one species due to the relaxation of predation or competition of another
food chain
simple linear hierarchy of monophagous consumers
monophagous
primary producers consumed by primary consumers, consumed by secondary consumers, and so on; assumes there is a direct link from the autotroph to the primary consumer
food web
complex network of interacting species functioning as producers and consumers
energy transfer between trophic levels
-only about 10%
-autotrophs are abundant and top predators are rare (in number and in biomass) due to energetic limitations
biomass transfer between trophic levels
-biomass pyramid can be inverted (often in aquatic ecosystems) but energy pyramids cannot
why can biomass pyramids be inverted?
-primarily in aquatic biomes
-r (intrinsic rate of population increase) is high for autotrophs
-consumption of autotrophs by primary consumers is very high
why are predator : prey body-mass ratios higher in aquatic than in terrestrial habitats?
-gape limitation~ how big a
predator’s mouth is
-most aquatic predators engulf their
prey to avoid it sinking or being
swept away
why are the vast majority (80%) of predators larger than their prey?
-efficiency
-less risk
-easier handling
why is the energy transfer in aquatic ecosystems more efficient than in terrestrial ecosystems?
in terrestrial ecosystems, gravity is a factor~ requires cellulose, bones, and other indigestible things, making energy transfer less efficient
bottom-up regulation
primary producers limit the number of primary consumers that can be supported in a system by setting the energy available at the base trophic level
top-down regulation
-top consumers limit primary
consumers, which allows primary
producers (autotrophs) to thrive
-without top consumers, primary
consumers would eat all the green
material produced by autotrophs
-predators serve an important regulatory role in their ecosystems
green world hypothesis
ecosystems can be regulated by top-down limitations, bottom-up limitations, or both
trophic cascade
-reciprocal predator-prey effects that
alter the abundance, biomass, or
productivity of a population,
community, or trophic level across
more than one link in a food web
-the enemy of my enemy is my friend
-extension of top-down regulation~
autotrophs need top predators to
thrive
trophic levels
-autotrophs and heterotrophs (primary, secondary, tertiary, etc. consumers)
-only about 10% of energy is transferred between trophic levels
trophic ecology
the study of the structure of feeding relationships between among organisms in an ecosystem
global cycles
nitrogen, carbon, oxygen, and sulfur
local cycles
phosphorous, potassium, and calcium
reservoir
the total inorganic or organic material that is available to organisms
flux
the rate of movement between reservoirs
dynamic equilibrium
the balance of flux between reservoirs in a biogeochemical cycle
how have humans affected the carbon cycle?
transferred carbon from other sources to the atmosphere
-change in flux
-change in reservoir size
what is the primary way carbon is sequestered in oceanic biomes?
creates calcium carbonate to form the shells of marine organisms
how does increased atmospheric CO2 increase ocean acidity?
1) reacts with water to form carbonic
acid
2) carbonic acid readily breaks down
into hydrogen ions and
bicarbonate
-hydrogen ions lower the pH
3) existing carbonate that usually
forms shells with calcium instead
combines more readily with excess
hydrogen ions forming more
bicarbonate, creating a positive
feedback loop
ocean acidification
the ongoing decrease in the pH of the earth’s oceans, caused by the uptake of CO2 from the atmosphere
organic forms of nitrogen
found in amino acids, proteins, and more resistant nitrogen compounds
inorganic forms of nitrogen
ammonium ions, ammonia, nitrate, and nitrite
processes in the nitrogen cycle
fixation, ammonification (mineralization), nitrification, assimilation, and denitrification
biotic nitrogen fixation
the conversion of atmospheric nitrogen to ammonia by an enzyme called nitrogenase
abiotic nitrogen ammonification
the conversion of ammonia to ammonium ions
-occurs more rapidly when the pH is
low (more H+ ions)
biotic ammonification
when a plant or animal dies or an animal expels waste, and bacteria or fungi convert the organic nitrogen to ammonium ions
nitrification
the process in which bacteria change the oxidative state of ammonium ions to create nitrite or nitrate
assimilation
many plant species form mutualisms with mycorrhizal fungi to degrade nitrogen compounds and aid in amino acid absorption
-plants and fungi trade nitrogen for
carbon
denitrification
the reduction of nitrates back into atmospheric N2
-performed by bacteria
mass extinction
dramatic increase in the rate of species loss
anthropocene
the geological era in which humans have been dominant
holocene (anthropocene) extinction event
the most recent mass extinction event in history, caused by human actions
habitat destruction
the rapid conversion of a historic biome into an anthrome
introduction of species
the addition of species into a novel environment, outside of its historical distribution area
secondary extinction
the elimination of a species due to the elimination of another species; the indirect effect of human actions
overkill (overharvest)
the killing of more animals in a population than that population can recover by birth rate
evil quartet
1) habitat destruction
2) introduced species
3) secondary extinctions
4) overkill
evil sextet
the 6 principle drivers behind the holocene extinction event
1) habitat destruction
2) introduced species
3) secondary extinctions
4) overkill
5) climate change
6) extinction synergies
extinction synergy
the idea that drivers of extinction do not only add together, but reinforce one another to make an overall effect larger than the sum of its parts
planetary boundaries
guiding human development on a changing planet
