|The eagle against black|
Apart looking for ancient parallels the question I asked was, is this fur-like feathering based on nature? For this Google proved invaluable as a source of images of eagles. I found that one species of eagle that does have this type of feathering on the body, the Golden Eagle. This made sense to me, since it is the largest eagle that the Romans would have known of, and is because it is so majestic it became the symbol of the king of the Gods, Zeus.
|A golden eagle on Google|
|Golden eagle and carcass in winter|
The above images and others I have found, demonstrate that golden eagles have wispy long pointed feathers covering their neck and bodies down to their legs, that can look fur-like. Given the Roman and Greek interest in naturalistic depiction, this at least would seem to support the possible Roman date of this eagle. Now I needed to find other ancient Roman eagles with similar feathering of the body.