bio final

niche

range of abiotic or biotic conditions an organism can tolerate

spatial structure

pattern of density and spacing of individuals in a population

abundance

total number of individuals in a population that exist in a defined area (help us know if a population is thriving or near extinction)

density

the number of individuals in an area; high density in places where the population is most suitable; negatively correlated to the body size of a species 

dispersal

the movement of individuals from one area to another

dispersal limitation

the absence of a population from a suitable habitat due to barriers 

habitat corridor

strip of favorable habitat located between two large patches of habitat that facilitate dispersal

density independent

factors that limit population size regardless of the population’s density (natural disasters)

density dependence

factors that affect a population size in relation to the population’s density (disease, predation)

negative density dependence

when the rate of population growth decreases as population density increases (caused by limiting resources)

positive density dependence

when the rate of a population growth increases as population density decreases

phenotypic trade-off

a situation in which a given phenotype experiences high fitness in one environment, whereas other phenotypes experience higher fitness in other environments

phenotypic plasticity

solution to phenotypic trade off; the ability of a single genotype to produce multiple phenotypes; allows organisms to achieve homeostasis; natural selection favors this

torpor

brief period of dormancy

central place foraging

foraging behavior in which acquired food is brought to a central place (nest with young birds)

polygenic

when a single trait is affected by several genes; enables phenotypes to span a range of values in a population (human body weight)

pleiotropy

when a single gene affects multiple traits

founder effect

when a small number of individuals leave a large population to colonize a new area

bottleneck effect

when a large number of individuals in a population are drastically reduced due to an event, leading to a loss of genetic diversity.

allopatric speciation

the evolution of a new species through the process of geographic isolation; occurs when a single population is separated by a geographic event 

sympatric speciation

the evolution of new species without geographic isolation

polyploid

3 or more sets of chromosomes; gives rise to sympatric speciation

promiscuity

when males mate with multiple females and females mate with multiple males (no lasting bonds)

polygamy

a single individual of one sex forms long-term social bonds with more than one individual 

polygyny

a polygamous (more than one mate at the same time) mating system in which a male mates with more than one female 

polyandry

a polygamous (more than one mate at the same time) mating system in which a female mates with more than one male

factors that influence the probability of host infection

• Mechanism of transmission 

• Mode of entering the host 

• Ability of parasite to jump between species 

• Existence of reservoir species 

• Counterattacks to hosts immune system 

predator / prey

short, casual duration and high probability of death 

plant / herbivore

short, casual duration and low probability of death

parasitoid / host

long, close duration and high probability of death

parasite / host

long, close duration and low probability of death

limiting resource

a resource whose available quantity cannot meet a population’s requirement for it ; controls how high the population can grow

aposematism

warning coloration

batesian mimicry

when tasty species evolve warning coloration that resembles non-tasty species

mullerian mimicry

when many non-tasty species evolve a similar warning coloration

endomycorrhizal fungi

fungi characterized by hyphal threads that extend far out into the soil and penetrate root cells between the cell wall and cell membrane

ectomycorrhizal fungi

fungi characterized by hyphae that surround plant roots and enter between root cells but do not enter the cells

community stability

ability of a community to maintain a particular structure 

community resistance

amount a community changes when acted upon by a disturbanc

community resilience

the time it takes after a disturbance for a community to return to its original state

bottom - up control

if there are lots of plants in a forest (lots of food), the deer population (herbivores) will grow. more deer means more wolves (predators) can survive, as they have more prey; population of higher-level consumers (like herbivores and predators) is controlled by the availability of resources; More plants = More herbivores = More predators

top-down control

 if wolves (predators) are removed from an ecosystem, the deer population may grow rapidly. more deer means the plants may be overgrazed and start to decrease; population of lower-level organisms (like herbivores or plants) is controlled by the presence and number of predators; More predators = Fewer herbivores = More plants

exploitative competition

competition where individuals consume and drive down the abundance of a resource so no other individuals can persist (indirect)

interference competition

competitors do not immediately consume resources but defend them (direct)

allelopathy

when organisms use chemical to harm their competition

apparent competition

two species have a negative effect on each other through an enemy

thermodynamic principles

energy follows this; conservation of energy, entropy (randomness or disorder of a system) increases due to inefficiency, treats ecosystems (like earth) as giant thermodynamic machines

standing crop

 describes the total biomass (the amount of living material) of all the organisms in a specific area at a particular point in time; how much living stuff is present in an ecosystem at any given time; Determine by net primary productivity

primary production

the rate at which solar or chemical energy is captured and converted into chemical bonds by photosynthesis or chemosynthesis

net primary productivity

he rate of energy that is assimilated by producers and converted into producer biomass in an area (includes all energy that is not respired)

gross primary productivity

the rate at which energy is captured and assimilated by producers in an area

landscape ecology

field of study that considers the spatial arrangement of habitats at different scales and examines how they influence individuals, populations, communities, and ecosystems

intrinsic value

inherent value of a species; feel religious or moral obligations to preserve worlds species 

instrumental value

focus on economic value a species can provide (value of crops) 

provisioning species

benefits of biodiversity that humans use like lumber or water

regulating species

benefits of biodiversity that induce climate regulation, flood control, and water pollution

cultural services

benefits of biodiversity that provide aesthetic or spiritual value (like hiking to see a view)

supporting services

benefits of biodiversity that allow ecosystems to exist (soil formation)

declines in genetic diversity

Declines in genetic diversity can be caused by declining population sizes, inbreeding depression (when populations shrink, individuals are more likely to breed with closely related individuals), and the bottleneck effect (when a population is drastically reduced)

declines in species diversity

Species diversity is in decline due to habitat loss, climate change, overexploitation, invasive species, and pollution, which threaten ecosystems

biomagnification

the process by which certain harmful substances, like chemicals, become more concentrated as you move up the food chain (DDT)

biotic homogenization

the process where different diverse ecosystems become more similar to each other because of human activities (the variety of plants and animals in different areas start to look the same over time)

minimum viable population

the smallest population size that will allow a species to continue existing for the long term, without dying out due to inbreeding, lack of genetic diversity, or other risks