Mane Attraction - Alison Pearce Stevens

This article originally ran in the March 2013 issue of ASK magazine
MANE
Why do lions have manes? One scientist packs up her
toys and goes looking for an answer.
In the middle of Serengeti National
she slinks up to tickle his nose with the
Park in Tanzania, Africa, a lioness
tip of her tail. She’s chosen him as a
approaches two unknown males. One
mate.
has a mane that is light—nearly the
Too bad he’s just a bit, stuffed toy.
same color as the rest of his body. The
From the safety of her truck,
other lion’s dark mane stands out
Peyton West watches the lion through
against his lighter fur. The lioness pads
the view-finder of her video camera.
past the light-maned male. It’s the one
She is thrilled with the lion's behavior.
with the dark mane who’s caught her
She'd suspected that female lions
interest. She pauses, watching him, then
preferred males with dark manes—and
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text © 2013 by Alison Pearce Stevens
photos co
urtesy of
Peyton W
est
this female certainly does!
by Alison Pearce Stevens
Attraction
photo by Hok/Wikimedia CC BY-SA 3.0
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photo by Hok/Wikimedia CC BY-SA 3.0
Eventually, the lioness realizes
her new mate isn't going to return her
have them at all?
affections. She wanders back to her
Over 140 years ago, the great
pride. West and her assistant jump from
naturalist Charles Darwin suggested
the truck, bundle the two life-sized
that lions have manes to protect them
plush lions into the back, and return to
from attack by other lions. It made
camp.
sense. After all, it would be more
Why Do Lions Have Manes?
difficult to bite a neck protected by a
thick mat of hair. But West wasn't sure
Lions’ manes set them apart from other
about Darwin's idea—if manes were so
cats. But not all lions have them—only
important in defense, shouldn't all lions
adult males grow manes. No two
have them, even females? So she set
manes are the same. Some are very
out to test it.
light. Others are nearly black. Manes
She figured that if a mane acted as
can be long and shaggy, covering the
a shield, it should cover the part of the
shoulders and chest, or they can be
body that was most likely to be injured
short, covering just the head and neck.
in a fight. But when she looked through
Some are little more than a mohawk.
records of lion injuries, West found that
Those
wondering:
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much? For that matter, why do lions
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differences
got
West
Why do manes vary so
the head and neck were not attacked
any more often than other parts of the
How Does Your Hair Grow?
Hair is made by special cells in
pigment that colors skin and eyes.
cycles of activity and rest, which
the skin. The root of the hair sits
More melanin in the hair makes it
can last from a few months to
in a small pit in the skin called a
darker. Whether hair is curly or
several years. When a follicle
follicle. Hair itself is not alive—it
straight depends on the shape of
rests, the hair it was working on
contains no living cells. It is like
the
follicles
falls out, and a new hair starts.
a rope that cells make out of a
make round hairs (like spaghetti),
This means hair (and fur) is
protein called keratin. The hair-
which hang straight. Oval follicles
constantly
making
constantly
make flatter strands, which curl.
shedding. How long hair will get
sticking on more to the end of
Animal fur is hair too—we call it hair
depends on the length of the
the
follicle,
if it’s long, fur if it’s short. Hair is
follicles’ growing cycle. A longer
pushing the hair out. Hair gets
always growing while an animal is
active cycle means longer hair.
its color from melanin, the same
alive. Hair-growing cells go through
hair
cells
are
inside
the
hair
follicle—round
growing
and
body. She also found that neck injuries
a lion was sick or hurt, the longer, darker
are no more deadly than other injuries,
hairs in his mane fall out—a signal that
whether or not the lion has a mane. So
the lion is unwell.
manes did not appear to be very good
shields, after all.
Being able to judge the health of a
lion from his mane is
Why, then, do lions have them?
useful to researchers,
but West suspects
The Show-Offs
that lions use
Hair growth depends on many
this
things: age, general health, what an
animal eats, and hormones, chemicals
that control growth and aggression.
West wondered whether manes were
saying
something
about
the
lion
underneath. She asked a group of
assistants to rate the length and
CC
B
Y2
.5
darkness of lions’ manes from photos,
manes. She also discovered that when
ph
oto
b
y
males tend to have shaggier, darker
Ro
be
k/W
i
lion. She found that older and stronger
kim
ed
ia
then compared these to data about the
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information too. Females like healthy
mates who can provide food for cubs
and protect them. Male lions prefer to
avoid stronger males, who might injure
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or kill them in a fight. If a dark mane
indicates a strong male, lions should
pay close attention to that signal.
The Winning Mane
To test her idea, West needed to see
how
lions
react
to
intruders
with
different types of manes. But lions are
over the hill in search of the hyenas.
active at night, which makes them
When they spotted the dummy lions,
difficult to observe. And she had no way
they slowed. Keeping a wary eye on
of knowing where an intruder might
the plush intruders, they crept closer.
appear—what if she were on one spot,
Long before they got close to the
but all the action took place in another?
dummies, the lions shifted to one side,
The solution was to use life-sized
so that they approached one of the two
“dummies” with four fake manes: long
stuffed lions, rather than both together.
and dark, short and dark, long and light,
After many tests, West found that
and short and light. The enormous
females almost always approached the
stuffed animals had velcro around their
dark-maned male. Males, on the other
heads, which allowed West to swap
hand, usually angled up to the light-
one mane for another. That way she
maned
could see what was most important to
important to females—they went to
the lions: length, color, or both.
either length if the color was the same.
At dusk, West drove out to find
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photos courtesy of Peyton West
male.
Mane
length
wasn't
But males avoided long manes.
lions and set up two of her dummies.
At long last, West had answered a
Then she climbed back into her truck,
centuries-old question: Why does the
played a recording of hyenas, and
lion have a mane? It tells other lions
waited. It wasn't long before lions loped
what to expect.
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