Those backwards camels

In Bechorot 8a:

הכל משמשין פנים כנגד עורף חוץ משלשה שמשמשין פנים כנגד פנים ואלו הן דג ואדם ונחש ומ"ש הני תלתא כי אתא רב דימי אמרי במערבא הואיל ודיברה עמהם שכינה תנא גמל אחור כנגד אחור:

Or, in English (referring to the Point by Point Summary)

(k) In all species, the male faces the back of the female during mating, with three exceptions, in which both face each other - people, fish and snakes.
(l) Question: Why are these different?
(m) Answer: Hash-m spoke with [at least one of] each of them (the Nachash in Gan Eden, the fish that swallowed Yonah).
(n) (Beraisa): Camels mate facing away from each other.

In a recent post, Rabbi Slifkin referred to this last statement as one which is scientifically incorrect. Thus,

the statement that camels copulate back-to-back (which probably stems from the fact that, at all times other than during copulation, the camel's member is directed posteriorally)

While this indeed seems like a good possibility, I see two difficulties:

1. Surely they encountered camels on a daily basis there. This is a brayta, but I would guess that they had in Eretz Yisrael and in Bavel camels. And people owned camels, and would occasionally spot them mating. And so, someone should have said 'Nope, camels do not mate in this manner.'
2. For any scientific statement, but particularly for those which are incorrect, I would prefer if we could trace it to a statement by a Greek scientist / naturalist. We have seen this to be the case for many such examples (such as, for example, that the atalef, a nocturnal flying creature, lays eggs and nurses its young, which finds a match in a statement cited and rejected by Pliny the Elder regarding the strix).

It turns out that Pliny the Elder does make a statement that camels (and lions, lynxes, elephants and rhinoceroses) mate back-to-back. And for these others, I would guess (though I have not researched it) that their members are not generally directed posteriorally. 

However, scholars have researched Pliny's statement, and this is what they have come up with. In A medieval book of beasts: the second-family bestiary, by Willene B. Clark:

Thus, Pliny wrote that camels, lions, lynxes, elephants and rhinoceroses mate aversus, meaning 'at the rear', meaning in the normal stance of four-legged mammals hat people in an agricultural society would have seen often, and the word was somehow changed later to adversus, meaning 'back to back'.

Now, what should we do with the gemara in Bechoros? It seems to me that there are two possibilities.

1. We can assume that the scribal error in Pliny had already taken hold by the time the brayta was recorded, and so the faithfully rendered statement in the gemara is just a repetition of that, such that it is indeed erroneous.
2. We can try to work Pliny's original meaning into the wording of the gemara.

Let us try possibility #2. Well, גמל אחור כנגד אחור seems difficult to bear this meaning. But maybe we can kvetch it. Or we can make an emendation of the text to be גמל כנגד אחור, stripping out the first instance of the word אחור. Of course, if we do this, then it matches פנים כנגד עורף of the earlier statement in the gemara, with just a variation in word choice by different authors of statement.

We would also need to make sense of the reference to camels in this gemara in Bava Basra 93a, as to why this verb in particular is used by camels, when it is true for so many other animals as well.

But here is the rather effective disproof, assuming our girsa is correct. If we look to Bereishit Rabba on parashat Bereishit, in parasha 20, siman 3, we find:

הכל משמשין פנים כנגד עורף, חוץ מב' שמשמשין אחור כנגד אחור. 
גמל וכלב. 

וחוץ משלושה שמשמשין פנים כנגד פנים, מפני שהשכינה דברה עמהם, ואלו הן: 
אדם,
נחש,
ודג.

אדם, שנאמר: ולאדם אמר כי שמעת לקול אשתך. 
נחש, ויאמר ה' אלהים אל הנחש. 
דג, (יונה ב) ויאמר ה' לדג ויקא את יונה: 

This is from the aggadic material of the Amoraim of Eretz Yisrael, and they clearly designate the camel and dog as exceptions to the general rule of הכל משמשין פנים כנגד עורף.

Again, I have never seen dogs mating, but this does seem to be the case for dogs. Thus:

The male dog usually swings a leg over the female dog's back so that both dogs would stand end to end.

That would seem to force us back to position #1, that they were citing Pliny -- at least, Bereishit Rabba was -- but with the error in translation already encoded. Note the use of the term "usually". Thus, there are times when the male dog will not do this. If so, perhaps the exception of camel and dog are optional, which makes it much more difficult to falsify with a single observation. And then, that feature which Rabbi Slifkin mentioned, that "at all times other than during copulation, the camel's member is directed posteriorally", can come into play to help maintain this encoded error.