Hi Gerry, you wrote
> Thanks John. Yes, the depiction in question is the Behistun relief
at
> Persepolis. Is this the one you are referring to? I have a
question: how
> can the observer of a relief differentiate betwen a horse and an
onager?
The Behistun relief was carved for Darius the first in 519 BCE, not
the third millennium. The only portrayal of equine draft animals
from so early is one from Leonard Wolley's excavations at Ur showing
onagers pulling four wheeled chariots.
The onager was roughly the size of a mule or horse, but skeletally
resembled the donkey. The chief distinguishing mark is the tufted
tail, and the long donkey-like ears.
For an excellent site on Behistun have a look at
http://home.wxs.nl/~lende045/Behistun/Behistun.htm
Regards
John