Search results
Results from the WOW.Com Content Network
Sleep can follow a physiological or behavioral definition. In the physiological sense, sleep is a state characterized by reversible unconsciousness, special brainwave patterns, sporadic eye movement, loss of muscle tone (possibly with some exceptions; see below regarding the sleep of birds and of aquatic mammals), and a compensatory increase following deprivation of the state, this last known ...
The primary physiological and biochemical concerns for an aestivating animal are to conserve energy, retain water in the body, ration the use of stored energy, handle the nitrogenous end products, and stabilize bodily organs, cells, and macromolecules. This can be quite a task as hot temperatures and arid conditions may last for months, in some ...
[61]: 99 [57]: 69 They have the largest blood corpuscles (red and white blood cells) of any mammal, measuring 10 micrometers (4.1 × 10 −4 in) in diameter. [57]: 70 Unlike most animals, whales are conscious breathers. All mammals sleep, but whales cannot afford to become unconscious for long because they may drown.
This is an accepted version of this page This is the latest accepted revision, reviewed on 1 March 2025. Taxonomic group of semi-aquatic mammals Pinnipeds Temporal range: Latest Oligocene – Holocene, 24–0 Ma Pre๊ ๊ O S D C P T J K Pg N Clockwise from top left: Grey seal (Halichoerus grypus), Steller sea lion (Eumetopias jubatus), New Zealand fur seal (Arctocephalus forsteri), walrus ...
Diving reflex in a human baby. The diving reflex, also known as the diving response and mammalian diving reflex, is a set of physiological responses to immersion that overrides the basic homeostatic reflexes, and is found in all air-breathing vertebrates studied to date.
Apart from the relevance to predation, crepuscular activity in hot regions also may be the most effective way of avoiding heat stress while capitalizing on available light. Crepuscular flight activity is preferred by some animals, such as the walnut twig beetle, due to warmer temperatures, moderate wind speeds, and low barometric pressure. [7]
Hibernation functions to conserve energy when sufficient food is not available. To achieve this energy saving, an endothermic animal decreases its metabolic rate and thereby its body temperature. [3] Hibernation may last days, weeks, or months—depending on the species, ambient temperature, time of year, and the individual's body-condition.
The cold water can also cause heart attack due to vasoconstriction; [4] the heart has to work harder to pump the same volume of blood throughout the body, and for people with heart disease, this additional workload can cause the heart to go into arrest. A person who survives the initial minute of trauma after falling into icy water can survive ...