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How do
lightning bugs light up?
Lightning bugs, deep water fish, bacteria, and
other organisms that produce their own light are bioluminescent
(bio-loom-in-ess-ent). This means light produced by a living organism. A
lightning bugs’ light is produced by a chemical reaction in their
abdomen.
Lightning bugs contain special cells that hold a
material called luciferin. When luciferin mixes with the energy produced
by a cell and oxygen from the outside, light is produced that is the
pale yellow to reddish green that you see when a lightning bug lights
up.
Most bioluminescent organisms simply glow.
Lightning bugs are a step above, in that they can flash the light in
precision. The lightning bugs flash the light for two reasons: to
attract a mate and to attract prey. They must be precise in their
flashing. Any old flash will not do. Some female lightning bugs prefer
the male with the longest flashes, and some females prefer the male with
the quickest flashes. The difference in individual flashes is so small
that our eyes cannot detect it, but special scientific instruments, and
other lightning bugs, can see the difference.
Why do deer
shed their antlers?
Deer shed their antlers every year and then grow a
new set. The whole shedding process takes two to three weeks to
complete, while forming a new set will take all summer. Deer shed their
antlers between January and April each year following mating season. By
this time, the males no longer need their antlers to attract females, or
challenge other males.
Deer antlers are different from the horns found on
cattle, which are hollow. Antlers are filled with a honeycomb-like
structure. The mounting points on the heads of deer where the antlers
grow are called pedicles. These pedicles are the “buttons” on a button
buck. The next year, he will develop “spikes,” and by year three the
first “branch” will appear. As the deer matures, more and more branches
will grow each year.
While the antlers are growing, they are covered in
a layer of skin, called velvet. The velvet supplies the antlers with the
nutrients needed to build bone mass. The antlers grow rapidly for two
months, and when the velvet is no longer needed, it dies and falls off.
Usually, this process is speeded by the deer rubbing the antlers against
trees.
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