Coloration evidence for natural selection Animal coloration has been a topic of interest and research in biology for centuries. In the classical eraAristotle recorded that the octopus was able to change its coloration to match its background, and when it was alarmed.
Learn more about how ecosystems change over time. Evolutionary ecology also examines broader issues, such as the observations that plants in arid environments often have no leaves or else very small ones or that some species of birds have helpers at the nest—individuals that raise young other than their own.
A critical question for the subject is whether a set of adaptations arose once and has simply been retained Animal background ecology all species descended from a common ancestor having those adaptations or whether the adaptations evolved repeatedly because of the same environmental factors.
In the case of plants that live in arid environments, cacti from the New World and euphorbia see spurge Animal background ecology the Old World can look strikingly similar even though they are in unrelated plant families.
Physiological ecology asks how organisms survive in their environments. There is often an emphasis on extreme conditions, such as very cold or very hot environments or aquatic environments with unusually high salt concentrations.
Examples of the questions it may explore are: How do some animals flourish in the driest deserts, where temperatures are often high and freestanding water is never available? How do bacteria survive in hot springs, such as those in Yellowstone National Park in the western United States, that would cook most species?
How do nematode s live in the soils of dry valleys in Antarctica? Physiological ecology looks at the special mechanisms that the individuals of a species use to function and at the limits on species imposed by the environment. Behavioral ecology examines the ecological factors that drive behavioral adaptations.
The subject considers how individuals find their food and avoid their enemies. For example, why do some birds migrate see migration while others are resident?
Why do some animals, such as lion s, live in groups while others, such as tiger s, are largely solitary? Population ecologyor autecologyexamines single species. One immediate question that the subject addresses is why some species are rare while others are abundant.
Interactions with other species may supply some of the answers. For example, enemies of a species can restrict its numbers, and those enemies include predators, disease organisms, and competitors—i. Consequently, population ecology shares an indefinite boundary with community ecologya subject that examines the interactions between several to many species.
Population ecology asks what causes abundances to fluctuate. Why, for example, do numbers of some species, typically birds and mammals, change perhaps threefold or fourfold over a decade or so, while numbers of other species, typically insects, vary tenfold to a hundredfold from one year to the next?
Another key question is what limits abundance, for, without limits, species numbers would grow exponentially.
Biogeography is the study of the geographical distribution of organisms, and it asks questions that parallel those of population ecology. Some species have tiny geographical ranges, being restricted to perhaps only a few square kilometres, while other species have ranges that cover a continent.
Some species have more-or-less fixed geographical ranges, while others fluctuate, and still others are on the increase.
If a species that is spreading is an agricultural pest, a disease organism, or a species that carries a disease, understanding the reasons for the increasing range may be a matter of considerable economic importance. Biogeography also considers the ranges of many species, asking why, for example, species with small geographic ranges are often found in special places that house many such species rather than scattered randomly about the planet.
Community ecologyor synecology, considers the ecology of communitiesthe set of species found in a particular place. Because the complete set of species for a particular place is usually not known, community ecology often focuses on subsets of organisms, asking questions, for example, about plant communities or insect communities.
There are many large-scale patterns; for example, more species are present in larger areas than smaller ones, more on continents than on islands especially remote onesand more in the tropics than in the Arctic.
There are many hypotheses for each pattern.Figure 1 Key Camouflage Strategies in Animals and Plants. (A, B) A juvenile horned ghost crab (Ocypode ceratophthalma, A) and an alpine Corydalis plant (Corydalis benecincta, B) use background matching to blend with the background.
Scavengers are a type of carnivore that eat dead animals, or carrion. Vultures, hyenas, crabs, deep sea fish-talk about distance from the sun and must eat the dead things that sink to the bottom, bottom feeders.
Humans and bears are omnivores but a large and important subset of . The word ecology was coined by the German zoologist Ernst Haeckel, who applied the term oekologie to the “relation of the animal both to its organic as well as its inorganic environment.” The word comes from the Greek oikos, meaning “household,” “home,” or “place to live.” Thus, ecology deals with the organism and its environment.
The Background of Ecology is a critical and up-to-date review of the origins and development of ecology, with emphasis on the major concepts and theories shared in the ecological traditions of plant and animal ecology, limnology, and oceanography.
The animal ecology curriculum provides its majors with an understanding of ecological principles and processes and their applications to natural resource management. Animal coloration has been a topic of interest and research in biology for centuries. In the classical era, Aristotle recorded that the octopus was able to change its coloration to match its background, and when it was alarmed..
In his book Micrographia, Robert Hooke describes the "fantastical" (structural, not pigment) colours of the Peacock's feathers.