Ecology Terms

A group of individuals of the same species that live in the same area and interbreed, producing fertile offspring.

How individuals are distributed, or spread, throughout their habitat.

Non-living, referring to the physical and chemical properties of an environment.

Living organisms withing an ecosystem.

The movement of individuals or gametes away from their parent location. This movement sometimes expands the geographic range of a population species.

Spatial area where a species is found.

Climate patterns on a very fine scale, such as the specific climate conditions under a log.

Per capita population growth (r) depends on per capita birth (b), death (d) and net migration (m) rates.

Producing cones, and having leaves that do not fall off in the winter.

(of a tree or shrub) shedding its leaves annually.

Any of the world’s major ecosystem types, often classified according to the predominant vegetation for terrestrial biomes and the physical environment for aquatic biomes and characterized by adaptations of organisms to that particular environment.

The pattern of spacing among individuals within the boundaries of a population.

Change from population of solitary forms to population of company loving forms.

Rapid increase in population abundance. Something allowed the population to grow rapidly.

A sampling technique used to estimate the size of animal populations.

The study of changes over time in the vital statistics of populations, especially birth and death rates.

Relative frequencies of vital occurrences that affect changes in the size and composition of a population (e.g., birth and death rates).

A group of individuals of the same age in a population.

More offspring=less energy put into each one (r strategist), with many being low quality (most do not survive). Few high quality offspring=each likely to survive (k strategist).

Maximizing fitness-maximizing contribution to the gene pool of the next generation.

Reproduction in which an organism produces all of its offspring in a single event; also known as big-band reproduction.

Reproduction in which adults produce offspring over many years; also known as repeated reproduction.

(k) The number of individuals that can be supported in a given environment.

An s-shaped curve, representative of a growing population (N<k)

Referring to any characteristic that varies with population density (e.g., death rate).

When birth rate (b)=death rate (d)

Biological processes that counterbalance disruptive events.

Number of children per female over her lifetime. Replacement TFR=2.1 children, where births exactly replace deaths.

Zone of rapid temperature change.

The open-water component of aquatic biomes

The bottom surface of an aquatic environment

The narrow top layer of an ocean or lake where light penetrates sufficiently for photosynthesis to occur.

The part of an ocean or lake beneath the photic zone, where light does not penetrate sufficiently for photosynthesis to occur.

The shallow region of the ocean overlying the continental shelf.

In a lake, the well-lit, open surface waters far from shore

In a lake, the shallow, well-lit waters close to shore

Zones of temperature and nutrient levels

Having a deficiency of plant nutrients that is usually accompanied by an abundance of dissolved oxygen.

When the environment is enriched with nutrients, increasing the amount of plant and algae growth to estuaries and coastal waters. can be harmful to aquatic life.

The area where a fresh water stream or ocean merges with the ocean

Arthropods that live in shallow tidal waters. Have free-swimming larvae.

The removal of moisture from something (stopped Balanus barnacles from moving further up-shore).

Realized niche- the ‘observed’ niche that an organism occupies in the world.

Fundamental niche- the conditions in which an organism can survive and reproduce.

The concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population.

Chlorophyll containing organisms composed of a group of cells arranged in colonies or as an organism.

An ecological relationship between organisms of two different species that live together in direct and intimate contact.

An ecological interaction that benefits each of the interacting species.

A symbiotic relationship in which one organism benefits but the other is neither helped nor harmed.

A symbiotic relationship in which one organism, the parasite, benefits at the expense of another, the host, by living either within or on the host.

Photosynthetic eukaryotes that live inside coral cells and produce carbohydrates and feed corals while getting CO2 and protection from the corals.

An interaction in which an organism eats parts of a plant or alga.

Number of species. Structures a community.

The different feeding relationships in an ecosystem, which determine the route of energy flow and the pattern of chemical cycling.

Food webs are made of food chains and represent the trophic interactions. (vertical) position in the food web is called a ‘trophic level.’

Dominant species have a large impact due to high biomass. E.g., barnacles.

Keystone species have a large impact despite low biomass and abundance. They are usually predators.

Large impact because the alter the physical environment. E.g., beavers.

Impacts of the top predators extends to lower trophic levels.

Higher trophic level reduces abundance or biomass of lower trophic level.

Lower trophic level controls abundance or biomass of higher trophic level.

Abrupt shift to a very different and persistent community. E.g., kept to urchin barrens.

An organism, virus, viroid, or prion that causes disease.

Pathogens must move between hosts.

Direct-pathogens move from one host to the next.

Indirect-pathogens use another organism (vector) to help them move.

An organism that transmits pathogens from one host to another.

The larger participant in a symbiotic relationship, often providing a home and food source for the smaller symbiont.

Migratory birds move ticks to new locations.

The total number of individuals in a population who have a disease or health condition at a specific period of time.

Photosynthesizing microscopic protists and bacteria that provide food for a wide range of organisms.

Small crustaceans that eat phytoplankton.

Living and non-living components that are connected organism-to-organism and organism-to-physical environment.

An organism that obtains organic food molecules without eating other organisms or substances derived from other organisms. Autotrophs use energy from the sun or from oxidation of inorganic substances to make organic molecules from inorganic ones.

An organism that obtains organic food molecules by eating other organisms or substances derived from them.

Dead organisms. Decomposers obtain chemical energy and nutrients from detritus.

Energy from the sun.

The conversion of light energy to chemical energy stored in sugars or other organic compounds.

Ecosystems lose heat energy through respiration. CO2 is returned to the atmosphere.

The process in which living organisms integrate nutrients from various external resources to their body and utilizes them to satisfy the energy demands required to stay alive. NH4+→organic N, NO3- → Organic N

Total light energy captured by plants

Plant growth rate (energy accumulated as biomass).

Energy (biomass) accumulated in all ecosystem components (per unit time).

-Plants capture energy

-Energy stored as biomass in all components

-Heat energy lost from all components

Nitrogen. An element that must be added for production to increase in a particular area.

An informal term applies to any eukaryote that is not a plant, animal, or fungus. Most protists are unicellular, though some are colonial or multicellular.

Bacteria that obtain energy via photosynthesis.

Any chemical cycle that involves both biotic and abiotic factors.

Created in the second step of the bacteria driven Nitrogen cycle-Nitrification (NH4+→NO3-).

Created in the first step of the bacteria driven nitrogen cycle -N-fixation (N2→NH4+).

NH4+→NO3-

NO3-→N2

N2→NH4+

Agriculture increases rates of N-fixation by growing legumes.

Excess water removes water-soluble nutrients out of soil, by runoff or by drainage.

A positively charged ion

Excessive primary production (growth) due to overload of nutrients.

Decomposition of algae leads to O2 depletion, low O2=fish and others die.

Increased through fossil fuel use. The input of reactive nitrogen from the atmosphere to the biosphere.

Those with more appropriate behaviour pass on more genes and are more likely to survive and produce offspring.

Selflessness; behaviour that reduces an individual’s fitness while increasing the fitness of another individual. E.g., the Pika call.

Behaviour should have a fitness advantage. Altruism doesn’t follow this law.

Selection for an act that enhances relative’s reproductive success.

Shared genes (r) (C<r*B)