Search results
Results from the WOW.Com Content Network
Amphibians are ectothermic, anamniotic, four-limbed vertebrate animals that constitute the class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all tetrapods excluding the amniotes (tetrapods with an amniotic membrane , such as modern reptiles , birds and mammals ).
It assumes an economy with one consumer, one producer and two goods. The title " Robinson Crusoe " is a reference to the 1719 novel of the same name authored by Daniel Defoe . As a thought experiment in economics, many international trade economists have found this simplified and idealized version of the story important due to its ability to ...
However, many amphibian declines or extinctions have occurred in pristine habitats where the above effects are not likely to occur. The causes of these declines are complex, but many can be attributed to emerging diseases, climate change, increased ultraviolet-B radiation, or long-distance transmission of chemical contaminants by wind.
In captivity, the predatory behavior amphiuma display depends on the presence or lack of food. Amphiuma will remain inactive when food is absent, and will become more active once food has been introduced into their habitat. [12] This shows that the amphiuma, although ancestral to many amphibia, has developed a deductive approach to its predation.
Consumer–resource interactions are the core motif of ecological food chains or food webs, [1] and are an umbrella term for a variety of more specialized types of biological species interactions including prey-predator (see predation), host-parasite (see parasitism), plant-herbivore and victim-exploiter systems.
Underconsumption is a theory in economics that recessions and stagnation arise from an inadequate consumer demand, relative to the amount produced. In other words, there is a problem of overproduction and overinvestment during a demand crisis.
See the consumer behaviour article for an overview. Consumer behaviour is a multidisciplinary field which is integral to industrial psychology and aspects of household economy studied in microeconomics. Consumer behaviour also means the actions shown by consumers while making decision to select household and consumer items.
Greater siren out of water. Greater sirens are carnivorous and prey upon invertebrates (such as insects, crustaceans, gastropods, bivalves, spiders, molluscs, and crayfish) [11] and aquatic vertebrates (such as small fish) [11] with a possible preference for molluscs (such as snails and freshwater clams), [8] [12] although they have been observed to eat vegetation such as algae.