Do
whales have hair ?
Some do. Whales are mammals just like us and they grow
hair just like us too - except the hair is very specialized.
Most people
think of hair on the exterior skin surface, but whales grow hair
inside their mouths. The hair is called "baleen" and
it is what the
blue whale, fin whale, right whale, humpback whale,
and gray whale use to filter water and extract food. As
whales move through the water they feed by opening their mouths
and taking in gallons of water. They filter this water to extract
the small animals as food using the baleen. By passing the water
through the baleen, the whales can expel
the water and hold back the the animals in the water for food.
The baleen acts like a sieve.
How
is hair loss and finger length related ?
The ratio between the lengths of the second and
fourth finger digits (your index finger is the first finger and
your pinky finger is the fifth finger) shows sexual dimorphism.
The ratio is lower in men than in women, and is thought
to
be determined
by
in utero
through exposure to androgens. Differences in the second and fourth
finger digit ratios between members of the same sex have
been linked to a variety of characteristics
including reproductive success, aggressive behavior, athletic
prowess and sexual orientation. Recent research has shown that
in non-bald men aged over 50 the second digit to fourth digit
ratios were significantly higher than in bald men. It is
generally thought that male androgenetic alopecia is due to the
post-pubertal effect of androgens in genetically
predisposed men. However, it is possible that in utero exposure
to androgens may also contribute to the subsequent development
of
scalp hair
loss.
What is the relationship between hair, teeth, nails, and horns?
Keratin! Hair, teeth, nails and horns are all basically the same
thing at the biochemical level. They are all made of the same
main ingredient
- keratin. Keratins are proteins,
long chains (polymers) of amino acids. Keratin proteins form the
cytoskeleton (miniature skeleton within a cell) of all epidermal
cells. Keratin filaments run within a cell from the inside of
the
outer membrane to weave a "basket" around the nucleus
of the cell. Keratins are a principle part of the cells in the
epidermis, hair, nails, feathers, hooves, horny tissues and the
enamel of teeth.
What is the origin of wigs and hair extensions ?
Wigs and hair extensions can be traced back to ancient Egypt
about 5000 years ago. Of course, the main use of wigs and hair
extensions in ancient Egypt was for cosmetic adornment. Surprisingly,
women’s
wigs were less elaborate than those of men’s and appeared
more natural looking. Extensions too, were not exclusively for
women and were also worn by men. There is archaeological evidence
that hair extensions were used in Egypt at least as early as 3400
B.C. For the most part,
hair extensions were used to fill out thinning hair or to make
regular tresses more luxuriant.
Wigs and extensions were almost always made of human hair and
were secured into or onto the real hair (or scalp) with beeswax
and plant resin. Sometimes, extensions were attached using thread
to fasten the extensions to their own hair. Many wigs had an internal
padding of date-palm fiber.
Wigs were not only a method of cosmetic
adornment, but were also sometimes used as a way to improve
cleanliness. Some ancient Egyptians shaved most or all of their
hair as a way
to avoid infection
by
head lice. To replace the shaved hair, they would wear wigs.
The wigs also protected them from the sun and helped to keep the
head
cooler. Hair is an insulator - it can help keep heat in the
skull, but in hot climates it can also help block heat.
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