Biology 1B: Ecology

climate

long-term, predictable atmospheric conditions of a specific area

* for biome, characterized by consistent temperature and annual rainfall ranges

biome

major terrestrial ecosystems at a global scale

temperature

degree of hotness or coldness of a body or environment

precipitation

rain/ frozen water that falls to Earth

elevation

space characterized upwards

latitude

measurement of distance north or south of the Equator

maritime climate

lower amplitude of seasonal temperature fluctuations

continental climate

higher amplitude of seasonal temperature fluctuations

Mediterranean climate

stable temperatures throughout the year and varied rainfall throughout the year

species distribution

geographical distribution of occurrence of animal and plant species aggregated by grid, region, administrative unit or other analytical unit

dispersal

the movement of individuals or gametes away from (potentially back to) their original location

dispersal limitation

limited by behavior

environment

everything in an organism’s surroundings

biotic limit

living components of the environment

abiotic limit

non-living components

behavior

the internally coordinated responses (actions or inactions) of whole living organisms (individuals or groups) to internal and/or external stimuli

performance curve

how a fitness metric varies with the abiotic environment

environmental gradient

a change in abiotic (non-living) factors through space (or time)

indicator species

an organism whose presence, absence or abundance reflects a specific environmental condition

richness

total number of species

eveness

relative similarity in abundance of species

composition

identities of which species are present

abundance

number of individuals

spatial scale

the characteristic scale at which measurements are reported

island biogeography theory

\-Islands’ closer to a mainland get more immigration of species than farther islands

\- Larger ‘islands’ have lower extinction rates (more ways for species to survive)

equilibrium richness

determined by the balance between immigration and extinction, and thus by island size and distance from mainland

luxury effect

richer people have more access to biodiversity

latitudinal diversity gradient

describes the pattern of changes in species richness with latitude

demography

the study of the vital statistics of a population and how they change over time

immigration

an animal establishes a home in a habitat because it has resources it can utilize or because the habitat is ideal for them

emigration

leaves its home because the habitat is no longer ideal for them and they need to find a more suitable environment

B-D model

model that assumes no immigration/ emigration

geometric growth

happen at discrete times

exponetial growth

happens continuously

rate of increase

* slope of log graph

R

rate of population growth per unit time

N0

initial number of individuals at t=0

life history

suite of traits related to a species’ life cycle and the timing of major events

per capita population growth rate

A metric of the average rate of population change for an average individual in the population

density dependence

changes in per-capita population growth rate with population size

equilibrium population size

point when birth rates equals death rates

logistic growth

exponetial model w/ carrying capacity

carrying capacity (K)

The population size at which N comes to equilibrium - a constant number

intrinsic growth rate (r)

describes how quickly population size will increase starting at very low density - a constant number

principle of allocation

Individual organisms have a limited amount of resources to invest in different activities and functions. Resources invested in one function are not available for another (a trade-off)

competition

A and B both try to acquire the same limited resource

predation

A kills B

herbivory

A eats B, may or may not kill B

parasitism

A lives on/in B, may or may not kill B

mutualism

A and B help each other

commensalism

B helps A, no impact on B

facilitation

general term for either mutualism or commensalism

dishonest mimicry

when an organism appears like an unpalatable species, even though it is palatable

honest mimicry

when an organism appears like an unpalatable species, and is unpalatable

exploitation competition

two predators (A,B) eat the same prey species. If A consumes the prey species better, then A indirectly harms B, because B gets less food

indirect mutualism

if three species (A,B,C) are predated/herbivorized by the same predator, and both A and B can make C a more attractive target for the predator/herbivore, then A and B indirectly help each other

cultural landscape

maintained by humans through regular interactions that promote/discourage certain species (e.g. burning, harvesting)

interaction network

diagram with arrows linking species that have a direct pairwise interaction

community

multiple species co-occurring in a place at a time, and possibly interacting with each other

coexistence

when several species co-occur together over time

intraspecific competition

competition between individuals of the same species

interspecific competition

competition between individuals of different species

competitive exclusion principle

If two species are competing for the same limited resource, the species that uses the resource more efficiently will eventually eliminate the other locally

fundamental niche

the full range of conditions or resources used in which a species could maintain a stable population in the absence of other species

realized niche

The actual set of conditions or resources used in which the species could maintain a stable population in the presence of other co-occurring species

niche partioning

allows coexistence by reducing competition

ex. each species has evolved to forage in certain parts of a tree

disturbance

a change in abiotic or biotic conditions in a community

community dynamics

changes the composition (richness, abundance, identity of species) over time

succesion

community dynamics after a disturbance

primary succession

following a disturbance, the community becomes empty, or approximately empty

secondary succession

following disturbance to an existing community, populations decline or only individuals of some life stages survive (seeds, spores)

gap phase regeneration

dominant canopy trees fall down due to old age or lightning/wind/landslide, opening ‘light gaps’, areas with more sunlight and available resources

early successional species

adapted to high disturbance

late successional species

adapted to low disturbance

facilitation

when species modify the biotic/abiotic environment in ways that help other species establish

tolerance

when species are not affected much by other species

inhibition

when species modify the biotic/abiotic environment that help other species establish (competing with them/synonymously

dispersal rate

reason for species composition change that results from when species do not get back to the area right away

serotiny

plant strategy in fire - Reproductive parts (cones or seeds) survive fire and open/germinate immediately after a fire – compete by having the highest colonization or dispersal rate

flammability

plant strategy in fire - Dead tssue accumulates and promotes fire spread – compete by killing one’s neighbors, then survive beaer, or resprout first

disease

a harmful condition affecting an individual, sometimes reducing its growth, survival, or reproduction

biological pest control

the use of living organisms to suppress pest populations

biological warfare

deploy organisms to spread disease, killing the people or organisms a group of people depend on

parasite

An organism that feeds on cell contents/tissues/fluids of a host while in or on the host organism; harm but usually do not kill their host.

host

living organism that acts as a harbour for invading pathogenic organisms

hyperparasite

parasite that has a parasite

pathogen

An organism or virus that causes disease (not necessarily living on/in a host)

metapopulation

many patches, each with populations, linked by immigration/emigration of individuals

biotic reservoir

locations where pathogenic species live when parasitizing a host

environmental reservoir

locations where pathogenic species live when not parasitizing a host

zoonotic disease

one that typically has non-human biotic reservoirs but which can ‘jump’ to a human host

contact transmission

direct movement from one host to another (for humans, via sex, birth, etc.)

vehicle transmission

indirect movement from one host to another via aerosols, water, dust, etc., possibly also via life stage in an environmental reservoir

vector transmission

indirect movement from one host to another via another biological host species (ex. bubonic plague via rat __)

SIR model

model for spread of disease: assumes a single population, single host species only

* susceptible
* infectious
* recovered

R0

average # of people infected by each sick person

traditional ecological knowledge

Western term used to summarize understandings of different Indigenous peoples

photosynthesis

solar energy is captured by formation of C bonds in compounds that are stored in organism

respiration

metabolic reactions release chemical energy, and in doing so return carbon to the environment

net primary productivity (NPP)

remaining glucose available to be laid down as new material - biomass