BIO120: Ecology

Ecology

The study of the interactions between living things and their environment

Population

All members of the same species who live in a specific area

Community

All the individuals (of various species) that live in the same area

Environment

The sum of all the biotic and abiotic elements that live in a specific area

Ecosystem

Interactions between the biotic and abiotic factors in a specific environment

Biotic

Living things (eg. plants, animals, fungi, bacteria)

Abiotic

All the non-living things in an environment (water, sun, rocks,)

Range

The geographical area or habitat where the species live

Dispersion

The movement of individual organisms from their birthplace to other locations for breeding

Sixth Extinction

A period of mass species extinction caused by human activity such as burning antropogenic greenhouse gases via the overconsumption of fossil fuels

Ecological Niche

The combination of physiological tolerances and resource requirements of a species; a species' place in the world

Eccentricity

The orbit of the Earth around the sun is an ellipse; this ellipse can vary from a more circular to a more elongated orbit

Tilt

The Earth's tilt varies between 22.2 and 24.5 C; the greater the tilt, the more temperature variance

Precession

Change in the orientation of the rotational axis, a gradual wobble in the orientation of the Earth's axis

Hadley Cells

Located near the equator, heated air rises and air cools when it rises, 5-10 C/km; as air cools, water vapour condenses and falls as rain near the equator, air warms again as it falls; dry, high-pressure areas at +/- 30 degrees latitude

Ferrel Cells

Mid-latitude cells, around +/- 30 to +/- 60 degree latitudes, behaviour opposite of Hadley cells, dry and wet air opposite of Hadley

Polar Cells

The cells most toward the poles, above +/- 60 degrees in latitude

Intertropical Convergence Zone (ICZ)

Shows as lines of rain clouds across pacific, shifts seasonally, producing rainy and dry seasons in some parts of the tropics; causes the climate to have little seasonality and it to be continuously rainy in South America

Westerlies

40-50 degree latitudes, blow west to east

Trade Winds

20 degree latitudes, blow east to west, also known as prevailing winds

Gyre

Any large system of circulating ocean currents, particularly those involved with large wind movements

Coriolis Effect

Circulating air is deflected toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere

Ekman Spiral

A consequence of the coriolis effect where each successively deeper layer of water moves more slowly to the right or left, creating a spiral effect

Continental Slope

A steady incline of the seafloor of the ocean

Continental Shelf

A gradually sloping area that borders each continent

El Nino

This occurs when trade winds weaken or sometimes reverse, this allows warm surface water to move eastward; it is associated with convection and produces rain clouds over the western coast of Southern America

La Nina

Opposite of El Nino, tends to follow an El Nino, occurs when there are increased trade winds

Southern Oscillation Index (SOI)

A standardized index based on the observed sea level pressure (SLP) differences between Tahiti and Darwin, Australia

Ecological Niche Modelling

Uses data from a species' present distribution to predict where a species can live; useful for modelling biological invasions, how species' ranges may shift as climate changes, spread of vector-borne diseases; usually relies on climate data; also called distribution modelling

Physiology

The study of how organisms acquire energy and nutrients and tolerate physical conditions

Physiological Eccology

The study of physiology in the context of an organism's ecology

Critical Temperature

Temperature at which animal loses the ability to do one of their critical processes

Homeotherms

An organism that maintains its body temperature at a constant level, usually above that of the environment, by its metabolic activity

Poikilotherms

An organism that cannot regulate its body temperature except by behavioral means such as basking or burrowing

Radiation

Heat transfer by electromagnetic radiation

Conduction

Transfer by direct contact with substrate

Convection

Heat transfer mediated by moving fluid

Evaporation

Efficient cooling from wet surfaces

Redistribution

Circulatory system redistributes heat among body parts, for example from the core to the appendages

Allen's Rule

Homeotherms tend to have smaller appendages at higher, colder latitudes

Insulation

More important than size/shape, layer of fur/wool/fat that keeps animals warm

Trade-Off

Being good at x may necessarily imply being bad at y

Constraints

Selection builds on what is already there, especially existing developmental programs, so tinkering, yes; fundamentally dress design, no

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods from carbon dioxide and water

Stomata

Small openings in plants that allow them to take in CO2 and take out H2O

Rubisco

An enzyme that accepts CO2 but at high temperatures often captures O2 instead of CO2

C4 Photosynthesis

The enzyme PEP carboxylase first accepts CO2, reducing photorespiration

CAM Photosynthesis

Plants close stomata during the day to reduce water loss, open stomata at night to let in CO2; photosynthesis still needs light, so they store CO2 as malate until daytime

Turbulent Airflow

This airflow is better for leaves because it promotes gas exchange, so leaves have ridges and bumps to promote it