Allison, I agree with Richard -- what you've got are marks made by rodent
incisors. Compare likely species based on width; may not be Rattus, but
rather some wild indigenous species. If the marks are rather wide, they
might be porcupine.
Keep in mind that carnivores do not chew bones with their incisors. Bones
gnawed by adult canines receive deep, rather widely-spaced, parallel marks
having a short stroke -- made by the animal holding the bone parallel to
its maxilla and then exercising its carnassial teeth upon it. If you align
the marks (gouges or scratches) thus made as vertical, the gnawed area is
usually much wider than high, rather than much higher than wide as in the
case of rodent. Bones gnawed by puppies or kits get chewed all over with
shallow to moderately-deep punctate "dents" so that the bone winds up
looking like the butt of an old cigar. Bones chewed by hogs wind up as
chips.
I've never seen a cat-chewed bone but the only cat in NA likely to be
involved would be a puma; I imagine puma-chew would probably look more
similar to coyote-chew than to rodent-chew. Maybe somebody else can fill
us in on what bones gnawed by medium to big cats wind up looking like. --
Cheers -- Deb Bennett
> Allison
>
> I think you are correct about being cautious in attributing these marks to
> a carnivore.
>
> The appearance, spacing, and size of the marks suggest to me that the
> bones were gnawed by some species of rodent - probably by the incisors of
> a rat.
>
> Richard
>
>
>
> -------- Original Message ----------
>
> Hey zooarchs,
> I keep going back and forth about IDing the animal that gnawed on
> this bone. There are almost parallel U-shaped grooves all along the
> proximal-anterior end of the phalanx, which was curiously found (in
> the lab, at least) as part of an intact articulation from metapodial
> to third phalanx.
>
> I can see what looks like a few punctures near some of the grooves on
> the anterior surface. It also looks somewhat chewed away.
>
> I'm so sure it's some sort of carnivore. It doesn't matter the
> species so much, but I have a nagging worry it's something other than
> carnivore, since this bone was not carried away or even lost from the
> rest of the foot.
>
> Anyone care to take a quick look?
>
> http://allison-grunwald.tumblr.com/post/149137889524/bison-antiquus-first-phalanx-with-modifications
>
> Many thanks,
> Allison
>
>
>
>
>
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