unit 3: ecology Flashcards
how an organisms structure, physiology, and behavior meet environmental challenges
organismal ecology
group of individuals of the same species
population
group of populations of different species in an area
community
organisms in an area and the physical factors with which they interact
ecosystem
mosaic of connected ecosystems
landscape
global ecosystem (sum of all ecosystems)
biosphere
individuals make up populations which make up species which make up communities
true dat
where is solar energy the strongest
equator because direct sunlight
why is solar energy weaker at the poles
rays are diffused over a greater distance
where does surface air move to
areas of low pressure
when rising air departs, surface air fills in gaps, creating
wind
air cools as it rises and cold air can hold less moisture, causing
cloud formation and rain
what creates cells
heating and rising of air, air pulled to fill voids
when air descends
surface pressure is high
when air rises
surface pressure is low
which direction does wind move at the surface
from areas of high pressure to low pressure
where is there lots of rain
areas of low pressure (equator)
where is there very little precipitation and deserts
30 degrees north and south
which direction does wind move approaching the equator from the north
to the west, as the earth is rotating
what winds move towards the equator
trade winds (left from south, right from north)
where does wind go at 30 north
from west to the east (westerlies)
what causes bending of wind towards the equator due to earths rotation
coriolis effect
wet on west side of a mountain, dry on east due to wind from east side
rain shadow
at the equator, where is wind always blowing
east to west
equatorial winds push water
towards the west
equatorial winds move water cause
upwelling zones (deep water rises on west coasts, nutrient rich, increases primary production)
amount of biomass of photosynthetic organisms created per unit area
primary production
where are continents drier
west sides due to high pressure cells
moist air over the ocean moves
toward the east side of continents
long term average weather, determined by solar radiation, wind, ocean circulation, and topograpy
climate
grew from cultural histories of observation and experimentation in the natural world, took root during age of exploration
ecology
study of the interaction of organisms with one another and the environment
ecology
the number of species in an area
richness
relative abundance of species in an area
eveness
what limits species distribution
abiotic and biotic factors, dispersal, and behavior
temperature, moisture, light, water, nutrients
abiotic factors
where is the sun in the winter
more directly on southern hemisphere
when is the angle of the sun highest in the north hemisphere
summer
in summer, the earths north pole is pointed
towards the sun
major ecological associations that occupy broad geo regions of land and water, defined by major species, annual cycles
biomes
characterized by growth of forms of dominant plant species, temperature, precipitation
terrestrial biomes
characterized by coral reefs, depth, flow, salinity
aquatic biomes
are there any biomes with high precipitation and low temperatures
no
global patterns of abiotic conditions on land match biodiversity and
production patterns
rate of enzyme activity increases as
low temperatures
lowest critical temp in vulnerable life stage limits
range of species
what determines moisture
slope and aspect
there is an increased rate of heat loss and water loss at higher
elevations
what leads to adaptations
water density, movement, light availability
what determines organism distribution chemically
water availability, oxygen availability, salinity, pH, (higher pH means more diversity), acid rain
in the northern hemisphere, the
south side of a mountain gets more direct sun
range of conditions necessary for a species to persist and the ecological role of the species in an ecosystem
biotic niche
fundamental niche
the broad conditions a species could live in
where is there the most species richness
large and close islands
larger islands have
more immigration and less extinction
what causes different water temps
lake turnover in seasons (cold water at top in winter, warm at top in summer)
where is there greater seasonality
between hadley and ferrel cells (middles of continents), as land heats faster than water and the middle of the continent is far from moderating effects of ocean
what affects distribution of biomes
changing land use (agriculture) and climate change
how do species adapt to climate change
adapt individualistically, move north and west
increasing temperature has led to
northward expansion of species range
individuals of one species occupying same general area and using same resources
population
demography of pop
births, deaths, age dist.
number of individuals per area
population density
pattern of spacing
population dispersion
BIDE
controls populations (births, deaths, immigration, emigration)
population dispersion can be
clumped, random, or uniform
mark recapture
number of total caught in recap divided by number recap with marks, times number marked originally (tells population estimate)
mark recapture EQ
C/R X M or (MxC)/R
what does mark recapture assume
population size hasn’t changed between sampling, no BIDE, short time frame
exponential population growth
unlimited, assumes continuous reproduction, individuals are identical, constant environment, unlimited resources
exponential growth EQ
dN/dt = rN
when is there exponential population growth
beginning of bounded pop growth (low population and high growth rates), density independent
what assumption of exponential group is not true
unlimited resources
logistic population growth
limited by carrying capacity K, assumes as N increases r decreases, density dependent
as pop approaches K, rate of growth slows
in logistic model
logistic growth EQ
dN/dt = rN (K-N/K)
focuses on births and deaths, mortality risks and life stage
demography and life histories
R adapted
many offspring, not a lot of care, unstable env
K adapted
fewer offspring, more care, stable env., populations close to K
focus on emigration and immigration, regular gene flow between geo separate units
metapopulations
migration can
restore subpops
source population
BR > DR, lots of emigration
sink pop
DR > BR, immigration
if sinks are too abundant
population can’t persist
corridors help increase
immigration
why are there death outbreaks
overshooting K
density dependent r
has delay
optimal life histories
maximize fitness
reproduce only once
semelparous
species can reproduce many times, can be seasonal
iteroparous
reproductive trade offs
early reproduction means more offspring in lifetime, but later reproduction increases reprod success
parental investment in offspring is traded off with
parental survival
adult survival drops as
more energy goes into reprod
future population growth depends on
the proportion of the pop in reprod age
how to stabilize a population
increase birth AND death rate, or decrease both
demographic transition
first high BR and DR, then DR declines, then BR declines, the both are low, then BR is lower than DR and population ages, BR may rebound
origin, implementation, short and long term, limits distribution
behavior
populations select habitats that
maximize fitness
finding food
foraging
animals maximize energy gain per unit time and risk
optimal foraging
profitability EQ
energy in food / search and handling time (P = E/t)
net profitability decreases with
larger prey
no time to catch and digest
type 1
search and handling time fixed cost, learn
type 2
low density, high efficiency
type 3
commonly encountered animals are
consumed more
increased foraging risk means
decreased profitability
predators maximize
energy value of prey
predators minimize
search and handling time
prey maximize
predator search time and handling time (camouflage, physical protection, intimidation)
prey minimize
probability of being eaten
costs of foraging
spending energy, no reprod, risk, conflict
fixed area where indv/group excludes others
territory
benefits of territory
exclusive access to resources
costs of territory
time and energy to maintain
larger territory means
larger body size
sexual selection
promotes traits that increase mating success
increased male population means
increased mate guarding
intersexual
choose mate based on characteristics
intrasexual
choose mate based on competition
female mate choice depends on
polygamy, monogamy, cost and benefit, selective pressure, environment
monogamy leads to
mate guarding, mate assistance, female enforced monogamy
polygyny
1 male, many females, 1 parent cares for young, causes sexual dimorphism, resource based
polyandry
1 female, many males, female is larger
behavior that appears to benefit others at cost to donor
altruism
reciprocal altruism
cost to altruism offset by likelihood of return benefit
kin selection
serve indv close relatives, alarm calling, favored by nat, sel when likelihood of alleles times beneit is greater than cost to donor
hamiltons altruism rule
rB > C (coeff of relatedness times benefit greater than cost)
eusociality
workers help queen raise offspring, increases vigilance and safety, many eyes hypothesis, selfish herd
decreasing prey means
less foo, predators decrease
decreasing predation means
less danger, prey increase
increasing predation meeans
prey decrease
increasing prey means
predators increase
competition, predation, parasitism, negative for one specie
antagonism
direct mutualism, indirect facilitation, positive for both sides
mutualism
no direct benefit for one species
commensalism
competition for a shared resource can lead to
competitive exclusion and character displacement
competition over shared resource leads species to
resource partition, specialize in different parts of a resource
two species with similar needs cannot coexist
competitive exclusion
increased differences in the niche spaces occupied by a species
resource partitioning
competition can lead to
differences in fundamental and realized niche
behavioral defense to predation
hiding, fleeing, herds, self defense, alarm calls
weapons of defense
armor, shells, quills, chemicals
camoflauge
cryptic coloring
warning colors show posion
aposematic coloring
harmless species mimic dangerous ones
batesian mimicry
two harmful species resemble each other
mullerian mimicry
evolution of plant physical, chemical, and behavioral defenses
herbivory
lots of seeds some years, barely any other years and the plant hides
masting
tough leaves, thorns, induced defenses
structural plant defenses
secondary compounds like toxic chemicals
chemical plant defenses
describe trophic interactions between species
food webs
includes trophic and other interactions
interaction web
measure of effect of one species on the population size of another
interaction strength
most abundant in biomass or number, affects the number of other species
dominant species
control the distribution of other species but are not the most abundant
keystone species
causes physical or chemical changes in the environment that affect other species
ecosystem engineers
alter food webs and community composition
pathogens
conditions change before competitively superior species reach carrying capacity
hutchinson paradox (allows species to coexist)
number of species present
species richness
how individuals are distributed
evenness or relative abundance
removes species and biomass, affects resource availability
disturbance
disturbance can act as a
keystone abiotic constraint
disturbance allows for
increased climate variability and healthier species
biome that depends on disturbance
chaparral
disturbing part of a landscape every 100 years increases patch diversity
intermediate disturbance hypothesis
the effect of a disturbance depends on
disturbance size, frequency, and rate of recovery
wisconsin oak savannas have
declined due to fire suppression
increased climate variability is altering
disturbance regimes in ecosystems
sequence of community and ecosystem changes after a disturbance
ecological succession
no soil exists when succession begins
primary succession
area where soil remains after a disturbance
secondary succession
the fraction of energy stored in assimilated food not used for respiration
production efficiency
percent of production transferred from one trophic level to the next
trophic efficiency
chemicals not processed that accumulate in tissue over an organisms lifetime
bioaccumulation
example of bioaccumulation
mercury in fish
amount of light energy converted to chemical energy by autotrophs
primary production
total primary production
gross PP (GPP)
GPP minus the energy used
net prim prod (NPP)
must be added for production to increase
limiting nutrient, limits the rate of production of biomass
amount of chemical energy from food that goes to new biomass
secondary productivity
increased phosphorous and algae
eutrophication
series of trophic interaction causing
changes in biomass and species composition
two species interacting with one or more intermediate speces
indirect effect
energy flow determined by predators
top down
resources that limit NPP determine energy flow
bottom up
energy flow and chemical cycling
ecosystem ecology
food webs and interactions
community ecology
energy cannot be created or destroyed
1st law of thermodynamics
how is energy lost
heat
every energy exchange increases the entropy of the universe
2nd law
matter cannot be created or destroyed
law of conservation of mass
includes pools and reservoirs, goes between organic and inorganic forms
nutrient cycling
weathering, erosion, fossilization
geological methods of cycling
dissolved in precipitation, atmospheric gas
chemical cycling
turnover rates
rates of nutrient cycling
total amount of nutrient in an ecosystem
pool size
tropical soil has
less nutrient pools, and increased rates of P and N cycling due to temp, moisture
controls rates of nutrient cycling
decomposition rates
where is decomposition faster
warmer and wetter climates
methods of nutrient input
wet or dry deposition, photosythesis, nitrogen fixation
losses of nutrients
leaching, dissolve, blow away, leave with an organism
carbon cycle
needed for PS, life, stored in sedimentary rocks, deep oceans, and soil, can be in atmosphere
nitrogen cycle
needed for many bio functions, pool in atmosphere, leaky cycle, fixed in soil, used in amino acids
phosphorous cycle
pools in rocks, decomposers release it, comes through weathering or decompositon, needed for calvin cycle
at first in plants
nitrogen is limiting
later in plants
phosphorus is limiting
nutrient excess can cause
eutrophication
nutrient deposition
produces N in plant available forms
accumulation in excess of plant demands causing forest decline, causes dead zone
N saturation
logging causes
nutrient losses
