Would we know that they were hooved, and did not have individually articulated toes? Internally, an elephant’s toe bones all point downwards, and don’t extend to the toenails. Would we be able to infer that?
The reason I ask is that I always want to imagine our extinct distant relatives, the sauropods, as having hooves as opposed to plantigrade feet with individually articulated toes, as they are typically depicted. There’s quite a bit of variation in todays mammals with hoovery, so could some of the great land lizards evinced some similar convergent foot styles?
Other animals than elephants have plantigrade, non-digital foot structure, hippos and rhinos being examples that come quickly to mind. We’d be able to extrapolate the elephant foot by analogy with them, based on your hypothesis (which I’m reading to say, “Presuppose the world as we know it except that elephants are known exclusively from their fossil remains.”).
You might also look into dinosaur feet, notably the odd toe variations of the Iguanadon, and the first-toe adaptation in sauropod forefeet.
First, let’s clarify some terminology. I don’t think you are actually asking about “hooves.” That just indicates a thickened nail on the end of the toe. There are plenty of hooved animals (e.g. deer, pigs) which have several well-separated toes. Sauropod toes were probably tipped by thickened nails (in some cases they had claws on the inner toes), although I am not aware that any fossils have been found. Hooves/nails are made of keratin, which does not fossilize well.
Also, elephants are anatomically digitigrade, even though they are functionally plantigrade. They walk on the tips of their toes, which are pointed downwards, but the heel is supported by a thick fibrous pad that makes the foot itself columnar.
Some sauropods probably shared this type of pad. In any case, in many the toes were so short that they probably would not have been separate, but formed part of a columnar foot. Note that the forefoot of Brachiosaurus was highly modified: it walked mostly on its metatarsals, the toe bones being extremely short.
I’m not sure which restorations you are looking at. Many of the ones I have seen show sauropods with columnar elephant-like feet.
Indeed. Here is a typical restoration of Brachiosaurus, and there aren’t any individually-articulated toes there. It’s also restored as being digitigrade. You can see the extremely short phalanges Colibri mentioned, as well.
And then, of course, we have fossilized footprints for sauropods. These show an elephantine print, rather than a splay-footed print with easily identifiable toes (as can often be seen in theropod footprints).
Elephants have hooves? I guess I’m not sure what hooves are, then – I thought hooves were adapted nails, made of keratin, forming a big hard, uh, thing. Whereas I thought elephant feet had individual toenails and a soft pad behind the toes. Is that a hoof?
Yes, elephants do have hooves. All that “hoof” means is a thickened nail on the end of the toe. Elephants, rhinos, and tapirs all have hooves, as do cattle, deer, etc.
And yes, the OP seems to have been asking not about hooves per se, but whether dinos had round feet without separate toes. But the question was somewhat confused.
[QUOTE=Colibri]
Yes, elephants do have hooves. All that “hoof” means is a thickened nail on the end of the toe. Elephants, rhinos, and tapirs all have hooves, as do cattle, deer, etc.
[QUOTE]
Okay, now I’m really confused, then. Don’t they have to walk on the nail for it to be a hoof? The elephant feet that I’ve seen pictures of seem to have individual toenails on the front of the foot, at least three of them … is there another toenail that forms a hoof or something?
I apologize if I’m being dense, but I thought that the sole of an elephant’S foot was a soft pad.
No. All “hoof” indicates is that the nail is thickened. Elephants have heavy thick nails on the toes, therefore they have hooves.
The toenails are the hooves. Not all hoofed animals walk fully on the hooves. Tapirs and rhinos don’t - the bottom of their feet is covered mainly by skin. You may be confused because you are thinking mainly of horses and artiodactyls (cattle, etc.) which do walk on the hoof itself, which covers part of the bottom of the foot.
From Merriam-Webster:
Main Entry: hoof
1 : a curved covering of horn that protects the front of or encloses the ends of the digits of an ungulate mammal and that corresponds to a nail or claw
2 : a hoofed foot especially of a horse
(emphasis mine)
Of course, M-W gets a little circular with its definition of “ungulate.”
Main Entry: un·gu·late
1 : having hooves
2 : of or relating to the ungulates
Oops. Sorry about messing up the formatting on that quote, Colibri. In my defense, I’m typing this in a darkened movie theater on a tiny handheld PC, over a not-so-responsive 33.6Kbps link through my T-Mobile phone. And I’m being distracted by Sky Captain and the World of Tomorrow, which thus far seems extremely good.
Aaaaaaah, okay, I think I see now. One of the links I got when I googled for “elephant foot” showed an elephant whose nails had been allowed to grow out to disturbing lengths because his keepers had neglected to properly maintain his feet, as he was evidently not amenable to pedicures. I’d find the page, but it won’t seem to come up on my lousy cellular connection at the moment, so … ah, here it is. Those nails certainly do look thick.
Well, that is very interesting – I always thought that “hoof” meant something that, basically, looked and functioned exactly like a horse’s hoof. Thanks for fighting my ignorance on this issue.
If you don’t mind one more question: is each of those nails on an elephant’s foot a hoof in and of itself? Or is the whole thing one hoof? I can’t quite tell from the definitions you quoted.
Each individual toenail is a hoof. According to this site, although elephants have five toes on each foot, each toe is not necessarily tipped by a nail/hoof.
Horses have only a single hoof on each foot, since they have only a single toe. Rhinos have three hooves on each foot, and tapirs have three to four. Artiodactyls (pigs, deer, cattle, etc.) generally have two large hooves on each foot, plus two smaller vestigial ones called dewclaws behind. (An exception is the hippo, which has four more-or-less equal hooves on each foot.)
Upon further review, it doesn’t appear that they’re articulated quite so well as I remember.
But the original question: Would we have been able to make a reasonably close approximation of an elephant’s foot, if we had only the fossils. I ask specifically because of the interesting (well, to me, anyway) situation as noted earlier of being anatomically digitigrade but functionally plantigrade.
In the case of elephants, we would be able to tell they were digitigrade by the position of the articulations between the toe and foot bones. We would probably also be able to deduce they were not functionally digitigrade because too much weight would have to be supported on too small a surface area. Therefore we could assume their feet had to be thicker around than the foot bones themselves would indicate.
In the case of dinosaurs, we can make some assumptions based on the length and articulations of the toe and foot bones. However, the precise degree of separation of the toes could not be unequivically determined, and this detail varies somewhat in reconstructions.
