Answer 1:
I am not a biologist, I do not know the answer
for sure. But this is such an interesting question
that I'd like to give a guess of the answer. First
we can think about why do we get itchy, or, how
does itchy feeling help animals in evolution. I
think the main reason some animals (mammals for
sure) get itchy is that it is an alert of skin
infection, or parasites. When we get itchy we know
something is wrong with our skin. But, crabs do
not have skin, they have exoskeleton (their
shell). My guess is that they do not have problems
such as skin infection like the mammals, so itchy
feeling does not seem useful for them.
|
Answer 2:
Great question! Have you ever noticed when
you feel itchy? For me, it's usually when I
roll around in grass, or if I accidentally touch a
plant that makes me itchy, or if I have chicken
pox. The reason you and I usually get itchy is
because our skin is unhappy because of
something we touched outside or sometimes because
something is going on under the surface of our
skin (like the virus chicken pox).
Most mammals feel itchy for similar reasons!
Mammals are animals like cows, horses, pigs, dogs,
and cats, which I'm sure you have probably seen
itching themselves before. When you think about
it, human skin and animal skin is actually kind of
similar--it's soft, it can move around a bit, and
it turns out it is sensitive to a lot of
things outside.
Crab skin, on the other hand isn't really a skin
at all. While you and I have skin on the outside
and a skeleton on the inside, a crab wears it's
hard skeleton on the outside to protect
itself...like a knight in shining armor! Because
of this, their skin isn't as sensitive as ours,
and though they can feel pain... no one has
actually tested to see if they get itchy. Maybe
next time you see one, give it a scratch.. but
stay away from the claws! Thanks for your
question. |
Answer 3:
Not in the sense that you do. Itches are
responses to irritations that may be related
to parasites, and scratching them might remove the
parasites. Crabs get different kinds of parasites,
and scratching wouldn't ever benefit them, so they
don't have the instinct to do it.
Click Here to return to the search form.
|
