Aristotle (I think, I don't remember that far back very well), gave an example of the problem of defining sharp boundaries. He considered a new constructed ship which is then used for maritime purposes (fishing, transportaion, smuggling, piracy,....) After each voyage the ship is repaired: perhaps new sails, oars, a new keel, new planking, etc. At some point, there are no original parts left; so is it the same ship? All changes were no more than an iota's worth.
This can be expanded to consider a fleet of ships in different states of upgrading; new ships being launched and old ones scuttled. At no point again is anything but a minor change made; but there are a pair of points in time for which no two ships in the fleet are the same. We can say that a complete change has taken place, but we are unable to define a point at which a change occured.
Language evolution is another example. It wasn't until the time of Charlemagne that people realized that they weren't speaking Latin anymore; they were speaking (old) French. The change was gradual; not like leaving Kansas in a cyclone. We have a pretty good written record of English back to pre-Chaucer days, so we can trace the developments; but it's isn't easy to read Beowulf without study so Beowulf clearly isn't Modern English although Shakespeare is.
Since y'all want to hang on to it as a fallacy rather than a property of evidence, then I re-assert that the fallacy must apply across the board which means to evolution as well. In my obituary post I summed it up as follows:
That's actually a wonderful analogy for evolution. If you think (as I've been guilty of myself) that it's a simple progression from Anglo-Saxon to Chaucerian English to Shakespearean English to fully Modern English, the striking thing is how sweeping the early changes are. Beowulf to Chaucer seems like a huge jump, from a practically Old German language to something we can almost but not quite read without footnotes. If it were a linear progression, it would seem to have started with an amazing saltation.
It's more complicated than that because Pre-Chaucerian Britain was incredibly balkanized compared to the later editions more familiar to us. Never mind the large unassimilated Celtic populations and the Dane/Viking settlements. Even the Anglo-Saxon areas (Essex, Wessex, Suffolk... I forget) had peculiar dialects coexisting and evolving in separate directions. Much of the changes were "hidden," you might say "unfossilized," by not being written down while more conservative versions were being recorded as literary forms.
It's a tree, not a straight line progression, and the record is fragmentary. Still, you can piece together what happened if you've a mind to see it.