Nova joins up at this point, to tag along on the expedition. After being at the site for a day or so, the searchers realize that poachers have been through here. Their evidence? Footprints around the cave. They haven’t seen that the site is hugely disturbed or anything like that, but there are footprints at this place that no one else is supposed to have been inside of for, possibly, millennia.
Luckily, the bones of the animal were eventually found (along with a ton of others), and they were analyzed. A lot of information was discerned about thylacoleo carnifex’s body structure, with extrapolations made about what this meant for his life. The show goes through all of this in great detail.
But, let us return to this poacher thing for a moment. There were footprints around the site that no one was supposed to have been inside of for millennia, so the show and the scientists assume it was poachers. Makes sense, right?
Not so much. While the episode makes much of the possibility of poachers at the site and the fear of the scientists, it neglects to link up the fact that Long received an email with a picture of the bones inside the cave. The picture was taken inside the cave. Are you making the connection that the show does not bother to explain?
Quite obviously at least one person besides the researchers was present at the cave within the last few millennia as a digital photograph was taken from inside the cave and emailed to one of them. Short of aliens or Marty McFly (and if it was Marty in the year 2025 who went back to 2005 to email the picture, the bones in the picture would have disappeared once Long discovered them). Of course, it is possible that there were poachers, that there is something else about the footprints that leads the scientists to determine that, but the episode gives no mention of it.