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Why did mammals select fur as a substitute of feathers?


Assuming that feathers are superior to fur by way of water conservation and insulation, I've all the time wondered: Why did mammals go the route of fur as a substitute of developing feathers? – Shane, Perth

An essential feature that distinguishes mammals from birds and other animals is that mammals have hair or fur and birds have feathers.

Mammals evolved from synapsids (like finbacks,) between 320 and 315 million years ago, while birds evolved. Theropod dinosaurs (like) about 150 million years ago. Therefore, hair and feathers evolved individually from different groups of animals.



Although each group of animals requires different degrees of insulation and waterproofing, different animals also use hair and feathers for added purposes – reminiscent of sensing their surroundings, and showing off. Together, all of those characters affect an animal's possibilities of survival and finding a mate to breed successfully.

Both fur and feathers are a part of it. Integration systemrelated to the external structures of the body.

Hair to regulate the warmth

Often, we associate hair or fur with insulation. Sheep's hair, often called wool, is well recognized for its insulating ability, and humans have built entire industries based on its properties.

Of course, mammals vary in number, type, and color of hair, and these characteristics are based on the needs of the actual mammal.

Hair is all the time related to sebaceous glands (which produce sebum, a water-repellent substance) and sensory receptors.

The naked mole rat (), a blind subterranean mammal, has a couple of scattered hairs (despite its name) – it uses these to maneuver through the enclosure. Sensory receptors.

Despite its name, hairs on the naked mole rat provide sensory information to assist it navigate underground.
From www.shutterstock.com

Elephants also seem like essentially hairless. However, they’re covered in hair of various length and density. Like their mammoth ancestors, modern elephants have a big volume-to-surface-area ratio. So quite than an insulator, modern-day elephant hair aids in heat loss and cooling.

Individual strands of hair are of various colours. The outer a part of the hairline is liable for the overall appearance of the animal, and subsequently its overall coloration. The inner a part of the hair strand is liable for insulation.

Hair or coat color affects the hair's ability to reflect and insulate solar radiation. Dark hair absorbs more radiant heat than light hair. For example, within the arid regions of Outback Australia, the dark uro (also often called the common wallaroo) avoids heat by moving. Out of the sun. The light-colored red kangaroo () spends most of its time in open areas.

Hair color is subsequently essential for species that use basking to warm themselves and conserve energy.

Just catching some rays – because I can.
From www.shutterstock.com

Ball for defense

Zebra (species) have black and white striped fur to cut back insect attacks and confuse biting flies. Scientists have found all-white or all-dark horse species and related species. Flies bite more easily than striped zebras..

Hair might also play a job within the defense of species reminiscent of porcupines, echidnas and hedgehogs. Porcupines have modified hair called quills, while echidnas and hedgehogs have hole spines, each covered in a thick layer of keratin. Animals even have bristles, underfur and/or hair between their quills or spines and on their bellies.

Hedgehogs curl up in a decent ball and expose their gnarled backs to predators. With a smile, ecdynas can curl up right into a ball or bury themselves, leaving their webbed backs exposed for defense from predators.

Echidna quills are literally modified hairs.
148286771@N02/flickr, CC BY-NC

Types of feathers

So, what about wings? Just as mammals have sensory receptors related to hair, birds have sensory receptors related to feathers. These enable birds to sense things like flies and other parasites.

There are two foremost forms of feathers: feathered feathers and down feathers.

The scaly wings have a rachis or shaft, which is branched closed, and branched with small barbule barbs. The underwings lack barbels, and are sharper in appearance.

The down feathers are liable for insulation, and are the feathers we use in our geese, while the down feathers assist in flight.

Different forms of feathers suit different purposes – flight, warmth and mating display. 1 – contour/flight feather, 2 – steering feather (tail feather), 3 – covering feather, 4 – piliform feather, 5 – bump feather, 6 – down feather.
Wikimedia Commons, CC BY

In some birds, the barbels on the molted feathers produce a powder that aids in waterproofing.

Birds even have one uropygial glands Located towards the bottom of their tail. It provides a wax-like substance to assist in cleansing and maintenance of feathers, and possibly provides additional waterproofing.

There is one other variety of feather, which could be very special: the pileplume. These feathers are utilized by males to display females and attract mates. In general, because of this male birds are sometimes more colourful than female birds.

The only function of those tail feathers is to look good.
Wikimedia Commons, CC BY

Mammals use different methods to display sex and attract mates. Deer use horns to indicate strength and agility to females, whales use song, while other mammals, reminiscent of cats, use scent.

Finding a mate is, after all, essential to producing the following generation. And feathers and fur play a key role in ensuring this.

The magnificent birds of paradise of New Guinea