Re: Horning in

[Dann Pigdon <dannj@alphalink.com.au>]

zone65@bigpond.com wrote:

> Are sheep & antelope horns covered in keratin? If so, surely it's a
> thin layer.

They certainly are. As ovicaprid skulls deteriorate the keratin
eventually flakes off, leaving a smaller (and much less ornate, in the
case of males) bony inner core. I was one of those gruesome kids who
collected all sorts of dead things - as I'm sure many future
archaeologists and palaeontologists did while they were young. :)

Technically, the skin of many (most?) creatures is covered in a thin
layer of keratin to help prevent pathogens from entering the body. I
don't see any reason why just about any type of creature with
keratinised skin (such as humans) couldn't eventually evolve some sort
of horn-like structure. 

Perhaps nails and hair (and feathers?) are also decended ultimately from
skin keratin?

-- 
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Dann Pigdon                   Australian Dinosaurs:
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://www.alphalink.com.au/~dannj/
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