Plant and animal terms

Abscisic Acid

A plant growth hormone that promotes seed dormancy by inhibiting cell growth. It is also involved in opening and closing of stomata as leaves wilt.

Actogram

A graph used in circadian research to plot activity (present or absent) against time.

Agonistic

Intraspecific behaviour that alternates between attack and escape.

Antagonist

Something opposing or in conflict with another.

Auxin

A plant hormone regulating growth by affecting cell elongation.

Biological Clock

The set of mechanisms within living organisms that link physiological processes with daily, monthly, or seasonal cycles, or with stages of development and ageing. It produces an endogenous rhythm that controls internal timing and can be entrained by a zeitgeber such as daylight, temp or similar.

Biological Orientation

The change in position of the whole or part of an organism in response to a stimulus, such as light.

Chemo-

Being affected by a chemical.

Circadian

A cyclical variation (rhythm) lasting approximately 24 hours under constant environmental conditions.

Circalunar

A cyclical variation (rhythm) lasting approximately 28 days under constant environmental conditions.

Circannual

A cyclical variation (rhythm) lasting approximately a year under constant environmental conditions.

Circatidal

A cyclical variation (rhythm) lasting approximately 12 hours under constant environmental conditions.

Crepuscular

Most active at dusk and dawn.

Critical Day Length

The photoperiod above which long-day plants flower and below which short-day plants flower.

Cytokinins

A group of plant hormones that retard ageing, promote cell division and bud formation, and sometimes promote flowering and break dormancy. They are produced in growing areas, such as meristems at tip of the shoot. Zeatin is a hormone in this class, and occurs in corn (Zea).

Diapause

A delay at some stage in the development of an arthropod, caused by stimuli indicating a change in environmental conditions and ended by specific stimuli.

Diurnal

Most active during the day.

Dormancy

A state of temporarily reduced metabolism.

Effectors

Cells or organs that respond to stimuli.

Endogenous

Caused by internal factors that are independent of external stimuli.

Entrainment

The process of resetting an internal clock so that it is synchronised with environmental rhythms.

Exogenous

Caused by external stimuli.

Free-running

A rhythm that proceeds independently of external changes.

Geo-

Caused by gravity.

Geomagnetic Cues

Using the Earth's magnetic field for orientation.

Hibernation

A period of animal dormancy during seasonal cold conditions, generally to survive a lack of food.

Homing

The ability of an animal to find its way home over unfamiliar territory.

Hormones

Chemicals secreted into a plant or animal and transported to another part where they affect growth or activity.

Innate

Coded for by genes.

-kinesis, Kineses

An orientation movement of an animal in which the stimulus governs the rate, but not the direction, of movement.

Klinokinesis

Rate of turning is determined by the intensity of a stimulus. Increased chance of an animal finding favorable conditions.

Learned

Behaviour that is modified by experience.

Long Day Plant

A plant that flowers when day length exceeds a certain minimum length.

Migration

The regular mass movement of members of a species for breeding and back again.

Mimicry

The similarity in appearance of one species of animal to another that affords protection from predators.

Nastic Responses

The response of a plant organ to a non-directional environmental stimulus.

Nocturnal

Most active at night.

Optic Lobes

Parts of the brain that contain primary visual centres.

Orthokinesis

Speed of an animals movement is determined by the intensity of a stimulus. Increased chance of an animal finding favorable conditions

Phase Shift

A change in the phase of a rhythm so that entrainment occurs.

Photo-

Response to light.

Phytochrome

A pigment found in most plants that acts as a light receptor. (P_665/P_{725) -} P₆₆₅ represents red, and P₇₂₅ represents far red.

Pigment

A natural substance in plant or animal tissue that gives it colour.

Pineal

A small gland at the top of the brain stem that secretes a hormone. In diurnal animals it produces the hormone melatonin to promote sleep.

Polyandry

The practice of a female mating with more than one male in a breeding season.

Polygamy

The practice of mating with more than one member of the opposite sex during a breeding season.

Polygynandry

An organised social system in which a female mates with several males and a male mates with several females within the social group during a breeding season.

Polygyny

Occurs when a male mates with more than one female.

Receptors

Cells or organs able to detect changes in the environment.

Short Day Plant

A plant that flowers when day length is less than a certain minimum length.

Star Compass

Using the stars to navigate.

Stimulus

An aspect or change in an individual's external or internal environment that causes a response.

Sun Compass

Using the Sun to navigate.

-taxis/Taxes

Directional movement in an animal towards or away from a stimulus.

Thigmo-

Response to touch.

Tropisms

A plant growth response to an external directional stimulus, causing the plant to curve towards or away from the stimulus.

Zeitgeber

An external environmental cue used to synchronise rhythmic behaviours with external events.

Hydro-

Response to water

Rheo-

Response to speed (e.g. in water currents)

Niche

The limits, for all important environmental features, within which individuals of a species can survive, grow and reproduce

Ecological niche

The 'occupation' or 'profession' of an organism or species

Gause’s Principle

Two species competing for the same resources cannot coexist if their ecological niches are the same

Arrhythmic

No regular pattern

Suprachiasmatic nucleus

In animals the SCN in the brain controls the biorhythm, detecting changes in daylength. When it gets to a critical length diurnal animals will court and breed.

Mutualism

Both species are positively affected from interaction

Commensalism

One species benefits, one unaffected

Competition

Both species are negatively affected from interaction

Predation, Parasitism, Herbivory

A relationship where one species benefits and one is disadvantaged

Amensalism

One species is disadvantaged, one is unaffected

Intraspecific

Within A species

Interspecific

Between othER species

Territory

An area defended against other members of the same species.

Apical meristem

A region of plant tissue found at the tips of shoots and roots that’s responsible for cell division and growth

Radicle

The first part of a seedling to emerge from the seed during germination.

Plumule

The primary bud that grows upward to form the plant’s shoot system after germination.

Turgor pressure

Pressure exerted by a cell’s interior fluid (water) that presses the cell membrane against the cell wall.

Day neutral plants

A plant that flowers regardless of day length.

Period

The amount of time between a behaviour repeating.

Pollination

The transfer of pollen grains from the male anther of a flower to the female stigma.

Mullerian mimicry

When 2+ poisonous species that may or may not be closely related share 1+ common predators and have come to mimic each other’s warning signals. Predators that avoid one species will avoid all other similar looking ones.

Batesian mimicry

Where a harmless (palatable) species mimics a dangerous (non palatable) species. Predators that avoid one species will avoid all other similar looking ones.

Parasitism

An exploitative symbiotic relationship where one species (the parasite) benefits while the other species (the host) is harmed.

Antibiosis

Where one organism produces chemical substances that harm, inhibit, or kill another organism.

Allelopathy

Where an organism releases biochemicals (allelochemicals) into the environment to influence the growth, survival, or reproduction of other nearby organisms.

Home range

The area in which an animal lives and travels.

Dominance hierarchy

The organisation of individuals in a group according to their status/rank within that group. Each individual dominates the individuals below them, but is subordinate to those above.

Alpha individual

The most dominant individual in a dominance hierarchy.

Pair bond

A strong, selective, and enduring social or mating relationship between two adult individuals that often leads to shared territory, cooperative resource defence, and bi-parental care of offspring.

R strategy

An organism produces many offspring at once that are left on their own. They develop quickly, remain small and reproduce young, and thrive in unpredictable, temporary or disturbed habitats.

K strategy

An organism produces few offspring per reproductive cycle that are raised by their parent/s. They develop slowly and reproduce later in life, and thrive in predictable, stable habitats.

Parental care

Any behaviour by a parent that increases the survival, growth, or reproductive success of their offspring.

Monogamy

The practice of mating with one member of the opposite sex during a breeding season.

Cooperative breeding

A social system where offspring receive care from individuals other than their biological parents known as helpers

Courtship

The period of time and the series of activities or rituals where individuals select a mate in the same species for reproduction.

Lek

A communal area where multiple male animals gather to perform competitive courtship displays to attract visiting females.

Cooperative

Intraspecific behaviour where an action by an organism benefits another individual (the recipient).

Altruism

Where an animal endangers themselves for the benefit of unrelated individuals.

Kin selection

Where an animal endangers themselves for the benefit of related individuals.

Aestivation

A period of animal dormancy during seasonal hot conditions, generally to survive a lack of food and water.

Adaptive significance

The specific role a physical, physiological, or behavioural trait plays in helping an organism survive and reproduce in its environment.