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Camouflage

Camouflage is a visual disguise. Without it, an animal would be recognised easily. If the natural colour of an animal makes it look like its surroundings, that is camouflage. A tigers stripes in the long grass, and the battledress of a modern sol ...

                                               

Chaparral

Chaparral is a shrubland or heathland plant community. It is found mainly in the U.S. state of California. Also in the northern portion of the Baja California peninsula, Mexico. It is caused by a Mediterranean climate and wildfire. A chaparral ha ...

                                               

Chromatophore

Chromatophores are pigment-containing and light-reflecting cells found in amphibians, fish, reptiles, crustaceans, and cephalopods. They are largely responsible for generating skin and eye colour in cold-blooded animals. Some species can rapidly ...

                                               

Community (ecology)

In biology, a community is all the living things in a place. It may mean a group of living things that are not dependent on other communities. It may mean a small group, such as the living things in a piece of dead wood. Populations of many speci ...

                                               

Competition (biology)

Competition is an interaction between organisms or species in which the fitness of one is lowered by the presence of another. According to evolutionary theory, this competition within and between species for resources plays a role in natural sele ...

                                               

Controlled burn

A controlled burn is a fire that is started on purpose, and kept under control. It is done by people who are trained in controlling a fire, with the right equipment and the right weather conditions. It is done to help the environment or to make a ...

                                               

Coral bleaching

Coral bleaching occurs when stony corals turn white. Stony corals are simple animals that form large reefs. The animals live in a endosymbiotic relationship with single-celled algae. To get sunlight the corals live just below sea level. The algae ...

                                               

Crypsis

Crypsis is a word in ecology which means "hiding". It refers to the ways animals avoid being seen, or otherwise detected. It also includes the situation when an animal is noticed, but is not recognised for what it is. It may be either a defence a ...

                                               

Decomposer

A decomposer is an organism that breaks down long chain polymers from dead organisms into smaller molecules. Decomposers are bacteria and fungi. What they do is use the parts and energy to build up their own materials, which are also organic. Dec ...

                                               

Defence against predators

For most animals, defence against predators is vital. Being eaten is not the only threat to life: parasites and diseases may also be fatal. But animals, especially small animals, are often eaten. Since life is about reproduction, anything that ke ...

                                               

Demersal

Demersal animals live on or near the bottom of the sea or lakes. The term is usually applied to fish. They occupy the sea floors and lake beds, which usually consist of mud, sand, gravel or rocks. In coastal waters they are found on or near the c ...

                                               

Desiccation

Desiccation is the state of extreme dryness, or the process of extreme drying. A desiccant is a hygroscopic water-attracting substance that causes desiccation in a moderately sealed container.

                                               

Ecological genetics

Ecological genetics is the study of genetics and evolution in natural populations. This contrasts with classical genetics, which works mostly on crosses between laboratory strains, and DNA sequence analysis, which studies genes at the molecular l ...

                                               

Ecological niche

An ecological niche is the part of the environment into which a species fits, and to which it is adapted. A shorthand definition of niche in biology is how an organism makes a living in a place. However, the term has been used in different ways. ...

                                               

Ecological yield

Ecological yield is the harvestable growth of an ecosystem. It is most commonly measured in forestry - in fact sustainable forestry is defined as that which does not harvest more wood in a year than has grown in that year, within a given patch of ...

                                               

Ecosystem services

Ecosystem services are processes by which the natural environment produces resources useful to people, as to economic services. They include: Pest and disease control Provision of clean water and air Carbon sequestration Pollination of crops Floo ...

                                               

Edge effects (ecology)

In ecology, edge effects are changes in population or community structures that occur at the border of two or more places of living. As the edge effects get bigger, there is greater biodiversity in the habitat at the border.

                                               

E. B. Ford

Edmund Brisco Ford FRS was a British ecological geneticist. He was a leader among those British biologists who investigated the role of natural selection in nature. As a schoolboy Ford became interested in lepidoptera, the group of insects which ...

                                               

Keystone species

A keystone species is a species which has a big effect on its environment relative to its numbers. The ecosystem depends on them, and would be much changed if they were not there. This is because they affect many other organisms in the ecosystem. ...

                                               

Krill

Krill are small shrimp-like crustaceans about an inch or so long, found in all the oceans of the world. In areas with nutrients, they occur in huge swarms, with more than 10.000 krill per cubic meter. They feed on phytoplankton and to a lesser ex ...

                                               

Law of the Minimum

The Law of the minimum, also called Liebigs law of the minimum, is a law about the growth of plants. Its states that the growth of a plant is limited by the resource, which is most scarce, and nor by the total amount of resources available. The l ...

                                               

Lessepsian migration

Lessepsian migration is the name given for the migration of marine species through the Suez Canal, between the Red Sea and the Mediterranean. It is named after Ferdinand de Lesseps, who built the Suez Canal. The Suez Canal joined two biospheres t ...

                                               

Microatoll

A microatoll is a circular colony of corals, near the surface of the ocean. Because the top is not in the water all the time, the corals at the top are dead. The corals which are not exposed to fresh air are still alive. The atoll will only grow ...

                                               

Microbial mat

A microbial mat is a multi-layered sheet of microorganisms, mainly bacteria and archaea. They were first described by Paracelsus, p1 but their full significance was not realised until the last quarter of the 20th century. Microbial mats grow most ...

                                               

Migration

For people see Human migration; for data see Data migration. Migration is when animals move on a regular cycle. For example, caribou in the Arctic go south in winter and return in summer when it is warmer. Many birds migrate, such as geese and st ...

                                               

Mimicry

In biology, mimicry is when a species evolves features similar to another. Either one or both are protected when a third species cannot tell them apart. Often, these features are visual; one species looks like another; but similarities of sound, ...

                                               

Nitrogen cycle

The nitrogen cycle is the way that nitrogen in nature is changed into many different forms that are used by living organism. Air is about 78% nitrogen. Nitrogen chemicals are needed for life. Nitrogen is a necessary part of proteins, DNA, and RNA ...

                                               

Over-harvesting

Over-harvesting means taking more from the land than it can replace. It includes extreme farming, grazing, fishing, and using fresh water. Over-harvesting is harmful in the long term. Forests or wetlands are hard to replace. Damage to nature hurt ...

                                               

Polymorphism

Polymorphism in biology is when two or more clearly different phenotypes exist in the same population of a species. The words forms or morphs are sometimes used. Polymorphism is common in nature. The most common example is sexual dimorphism, whic ...

                                               

Trophallaxis

Trophallaxis in biology refers the sharing of food by members of a community. It is most highly developed in social insects such as ants, termites, wasps and bees. The word was introduced by the entomologist William Morton Wheeler in 1918. The be ...

                                               

Wildfire

Wildfire is a general term which includes forest fires, grassland fires, bushfires, brush fires and any other vegetation fire in countryside areas. Wildfires occur in every continent except Antarctica. They can occur naturally and spontaneously, ...

                                               

Ethology

Ethology is the scientific study of animal behaviour, and a sub-topic of zoology. Ethology overlaps, to some extent, with psychology. Psychology is a social science which studies human behaviour, but many psychologists have done experiments on le ...

                                               

Collective animal behaviour

Collective animal behaviour describes and analyzes the behaviour of groups of animals. In these groups, the animals are often all of the same species. As an example, a school of fish will be made of mostly the same type of fish and a flock of bir ...

                                               

Courtship in animals

Courtship in animals is the behaviour by which different species select their partners for reproduction. Usually, the male starts the courtship, and the female chooses to either mate or reject the male based on his "performance". Many animals hav ...

                                               

Deimatic defence

Deimatic defence is when prey startle predators and so get time to escape. The predator gets a shock, and often jumps back when startled. Many prey use this tactic when a predator gets close. It is an anti-predator defence. This method is a fake, ...

                                               

Electroreception

Electroreception is the ability animals have to sense electrical sources. It is mostly found in aquatic or amphibious animals. This is because water helps the signals travel better than air. Some exceptions are the echidnas, cockroaches and bees. ...

                                               

Eye-spot (mimicry)

An eye-spot is an eye-like marking on the body of an animal. They are found on butterflies, reptiles, felids, birds and fish. Eye-spots may be a form of mimicry: the spot looks like the eye of a larger animal. Its function may be to draw a predat ...

                                               

Fight or flight response

The fight-or-flight response is a set of physiological changes that occur when an animal is threatened. The changes include increased heart rate, breathing rate and blood pressure. This response was first described by W.B Cannon. He found that an ...

                                               

Herd

A herd is a large group of animals. The term is used for mammals, particularly hoofed animals. Herding is a good example of collective animal behavior. Other terms are used for similar types of behavior in other types of animal. For example, a la ...

                                               

Mating

Mating is the pairing of opposite-sex or hermaphrodite organisms. It is usually for sexual reproduction. Some definitions limit the term to pairing between animals. Other definitions extend the term to crossing in plants and fungi. It is usual fo ...

                                               

Morgans canon

Morgans canon is a rule relating to animal behaviour, which states that it should be explained as simply as possible. It is named after British psychologist C. Lloyd Morgan. His idea was that people should only consider behaviour as, for example, ...

                                               

Neuroethology

Neuroethology is the study of animal behavior and its control by the nervous system. Neuroethology explores how the brain links stimuli to behavior. For example, many bats and Odontoceti have a special ability called echolocation. They use echolo ...

                                               

Play (activity)

Play is a word used in psychology and ethology to describe voluntary activities associated with recreational pleasure and enjoyment, and with early learning in mammals. Although everyone understands what the word means, it is extremely difficult ...

                                               

Releaser

A releaser is a stimulus from one animal to another, which causes a particular response. The releaser, or sign stimulus triggers an innate releasing mechanism in the receiver. The receiver then does its response, the fixed action pattern. This ki ...

                                               

Shoaling and schooling

Schooling and shoaling is a kind of collective animal behaviour by fish. Any group of fish that stays together for social reasons is said to be shoaling, and if the shoal is swimming in the same direction together, it is schooling. p365 About one ...

                                               

Territory (animal)

In ethology, territory is the area that a species of animal consistently defends against related animals. Sometimes it means areas defended against animals of other species. Animals that defend territories in this way are referred to as territori ...

                                               

Tonic immobility

Tonic immobility is a natural state of paralysis that animals enter, often called animal hypnosis. Its function is not certain. It may be related to mating in certain animals like sharks. It may also be a way of avoiding or deterring predators. T ...

                                               

Warning colouration

Warning colouration is how animals let other animals know that they are poisonous or dangerous. It is the exact opposite of camouflage. Warning colours are usually some combination of red, yellow, black and white. Alfred Russel Wallace, a British ...

                                               

Yawn

A yawn is a reflex. It involves a large, long taking in of air, the stretching of eardrums as the jaw opens wide, and last a breathing out. Pandiculation is the act of yawning and stretching simultaneously. It is easy to see when someone is yawni ...

                                               

Evolutionary biology

Evolutionary biology is a subfield of biology that studies how species start and change over time; or in other words, how species evolve. Someone who studies evolutionary biology is known as an evolutionary biologist. Evolutionary biology became ...