Re: Evolutionary Hair-raising Questions (Hear, hear!)

On Jul 11, 7:01 am, Tim Tyler <seemy...@xxxxxxxxxxxxxx> wrote:
MicroTech wrote:
Does anyone have an explanation to why humans came to evolve ear hair?
As I get older (now 64), I have found that, while thinning out
elsewhere, hairs are (somewhat annoying) sprouting in my ears. This is
quite common, especially in males.

Now, since this takes place long after the "prime" reproductive years,
what could possibly be the natural selection pressure which brings
this forth? One could also ask, what good are hairs in the ears,
anyway?

Ear hairs help prevent insects crawling into your ears while
you sleep and sucking on your juices.

Maybe not much of a hazard for you - but not all you ancestors
may have had it so good.

Hairs sprout in other unorthodox places as you age. Part of
the explanation for some of these "misplaced hair follicles"
involves senescence-mediated noise in the body's developmental
positioning cues - causing some cells to get confused about
exactly where they are - and thinking that they are in your
beard when they really shouldn't do so.


I like the theory that humans developed from a genetic change
that kept us physically in some ways from developing fully as
adult apes. Brain to body ratio, hair distribution etc. But as you
get older you get more *adult* ape-like, more body hair, balding
and so on ...

Differential delayed changes in parallel developments within the
body I think are used to explain how an insect can start as a
caterpillar, pupate and magically becomes a butterfly.

--
jc






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