Razoray,
The "pet theory" was already spelled here, and in fact was first advanced by snowfalcon2, re #254: that maybe they did it to conceal some human remains (to avoid arousing sensivities, let me say that he prefers another theory).
On second thoughts, I would expect most of the human remains to be found mixed, and probably bounded to, some heavy structures. But I know nothing about the water currents at the site.
Until the hipothesys arose, I had no idea of why one would like to tinker with the photo. Thatīs why I find the accusations of "conspiracy" deeply offensive. Iīm really curious about that "stain", but my inquiry is scientific since Iīm only searching for explanations.
But I also consider fair game if you only look at the photo and say, "I donīt see nothing". Iīm really not so sanguine about this, and donīt want to kidnap the thread. So this is my last post about this.