"Wild lynx, extinct in Britain for more than 1300 years..."
Hmm, I thought, 1300 years would place the extinction at 715 CE. How could they possibly know that? There are very few records for that particular period in British history (the Dark Ages, remember?). If we aren't even clear if King Arthur existed, how the heck do we know about lynx extinction? Internet searches give you the usual series of hops between unattributed links.
The answer is, we don't. It was originally assumed lynxes became extinct in Britain at the end of the ice age. But a 2005 paper carbon-dated a couple of lynx skulls; the younger dated to 455 +/- 20 CE (1560 years ago). And apparently a lynx might have been described in the Cumbric poem Pais Dinogad, though the translation is disputed. Pais Dinogad, which may date to 500 CE, originally was written in that long-extinct language, but survived because it was translated into the closely related medieval Welsh. 'Lewirn' in Cumbric means a medium-sized wild cat. Could be a lynx.
So the actual truth is there were almost certainly lynxes in Britain in 500 CE. And there aren't now. And there weren't in historical times for which we can trust the records, say after 1000 CE. That is what we know.
And this is what skepticism looks like.