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A dragonfly in its radical final moult, metamorphosing from an aquatic nymph to a winged adult.. In biology, moulting (British English), or molting (American English), also known as sloughing, shedding, or in many invertebrates, ecdysis, is a process by which an animal casts off parts of its body to serve some beneficial purpose, either at specific times of the year, or at specific points in ...
Mammals that have menstrual cycles shed the endometrium through menstruation instead. Humans, elephant shrews , and a few other species have menstrual cycles rather than estrous cycles. Humans, unlike most other species, have concealed ovulation , a lack of obvious external signs to signal estral receptivity at ovulation (i.e., the ability to ...
Male deer do these most often during breeding season. [citation needed] During the rut (known as the rutting period and in domestic sheep management as tupping), males often rub their antlers or horns on trees or shrubs, fight with each other, wallow in mud or dust, self-anoint, and herd estrus females together. These displays make the male ...
They do not feed; they pass much of their time hanging from the surface of the water by their respiratory trumpets. If alarmed, they swim downwards by flipping their abdomens in much the same way as the larvae. If undisturbed, they soon float up again. The adult emerges from the pupa at the surface of the water and flies off. [13]
Fish are among the main predators, picking nymphs off the bottom or ingesting them in the water column, and feeding on emerging nymphs and adults on the water surface. Carnivorous stonefly , caddisfly , alderfly and dragonfly larvae feed on bottom-dwelling mayfly nymphs, as do aquatic beetles, leeches, crayfish and amphibians . [ 27 ]
The highly vocal animals of the zoo that communicate with one another often, such as the elephants, flamingos and parrots, will be of particular interest, Griffioen said, to determine whether the ...
A dragonfly in its final moult, undergoing metamorphosis, it begins transforming from its nymph form to an adult. Metamorphosis is a biological process by which an animal physically develops including birth transformation or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation. [1]
Aquatic animals generally conduct gas exchange in water by extracting dissolved oxygen via specialised respiratory organs called gills, through the skin or across enteral mucosae, although some are evolved from terrestrial ancestors that re-adapted to aquatic environments (e.g. marine reptiles and marine mammals), in which case they actually ...