Fur adjective Of or pertaining to furs; bearing or made of fur; as, a fur cap; the fur trade. Fur verb To line, face, or cover with fur; as, furred robes. Fur verb To cover with morbid matter, as the tongue. Fur verb To nail small strips of board or larger scantling upon, in order to make a level surface for lathing or boarding, or to provide for a space or interval back of the plastered or boarded surface, as inside an outer wall, by way of protection against damp.
Fur noun the dressed hairy coat of a mammal. Fur noun dense coat of fine silky hairs on mammals e. Fur noun a garment made of fur. Fur noun a member of a Muslim people of the mountainous and desert regions of south-western Sudan. Fur noun the language of the Fur, an isolated member of the Nilo-Saharan family, with about , speakers.
Fur adjective relating to the Fur or their language. Fur Fur is a thick growth of hair that covers the skin of many different animals, particularly mammals. Fur Illustrations. Wool Illustrations. Popular Comparisons. Adress vs. Comming vs. Label vs. Genius vs. Speech vs. Chief vs. Teat vs. Neice vs. Buisness vs. Beeing vs. Amature vs. Lieing vs. Preferred vs. Omage vs. Finally vs. Attendance vs. Latest Comparisons Tubercule vs. Glyptal vs.
Faucet vs. Com vs. Destroyable vs. Aboriginal vs. Coelomate vs. Ocean vs. The normal length of the hair is an individual and species specific trait. So across the breadth of mammals, there are many norms for hair length, or fur length. Whats really different is the pattern of where it grows. Your dog or cat is basically covered with hair, whereas humans tend to grow hair in a few selected places. And thats one of the things that have changed through evolution in a number of mammal groups.
Whales, for instance, are mammals, but they are nearly hairless. We lack hair over a lot of our bodies. SA: Is hair a defining characteristic of mammals? NS: Its one of them. Other features that define mammals include producing milk to nourish the offspring.
SA: When does hair appear to have arisen? NS: We dont know, because the evolutionary lineage leading to mammals includes many fossil forms going way back in time, and hair, as a rule, doesnt fossilize.
So we cant know whether many of these relatives of mammals from the age of dinosaurs and earlier had hair or not. SA: Are there any impressions of hair in the fossil record? NS: There are very few fossils where there are impressions of anything in terms of soft tissue.
SA: How did hair evolve? NS: I think most evolutionary biologists believe that the evolution of hair is correlated with the evolution of endothermy, or warmbloodednessthe ability to produce internal body heatand hair is a very good insulator. If youre going to spend a lot of metabolic energy heating your body, its more efficient to hold on to that heat and not to lose it to the environment around you. So having hair as a means of insulation is one of the ideas about why we have hair.
Of course, there is no way for us to tell whether hair evolved first and then endothermy evolved, or whether endothermy evolved and then somehow hair evolved. We really dont know anything about these things. SA: Humans evolved in Africa, along with a lot of primates that are covered with fur. Human hair is less differentiated than the hairs on other mammals, having characteristics of both guard hairs and undercoat hairs, according to a manual on hair microscopy published in by the Federal Bureau of Investigation FBI.
But to begin to understand how fur diverged into the variety grown by animals alive today, we first need to take a step back in time , to about million to million years ago, to an era when something akin to fur is thought to have first appeared.
The first type of "hair" to emerge in mammalian ancestors was perhaps a modification of scales, "or some sort of hard, nonhair epidermal structures," Khidas told Live Science in an email. A need for insulation likely drove fur's evolution in early mammals, as it developed alongside another trait that differentiated them from reptiles: a consistently high body temperature that had to be maintained, using a process known as thermoregulation.
Rob Voss, a curator in the mammalogy department at the American Museum of Natural History in New York City, told Live Science that fur's most important role for mammals is to help with thermoregulation, preserving their internal temperature regardless of external conditions. In especially cold environments, terrestrial mammals such as the musk oxes, arctic foxes and polar bears rely on their thick coats to stay alive in frigid temperatures; dense fur traps a layer of air close to their skin, which helps to keep them warm.
Semiaquatic mammals, such as fur seals and otters, also have a thick covering of fur, with sea otters sporting up to 1 million hairs per square inch of skin — more than any other mammal. Slick-skinned marine mammals such as whales, dolphins and elephant seals lost their furry coverings long ago but replaced the fur's insulation with a thick layer of blubber that shields them from the cold, Voss explained.
But in warmer climates, larger mammal species tend to have sparser coverings of hair, as big animals are generally able to maintain their core body temperatures without much insulation, Voss said. Smaller animals with higher metabolic rates tend to have body temperatures that fluctuate more dramatically, and are therefore more reliant on furry insulation to protect them from dips in external temperatures, he added.
However, a mammal's fur can serve many purposes in addition to insulation. In some species, Voss told Live Science, guard hairs evolved into highly specialized protective structures — like the porcupine's and hedgehog's quills, or the pangolin's armor, where hairs fuse together to form tough plates.
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