Corrected entry: Butterflies and dinosaurs never coexisted. The oldest butterfly fossils date back 48 million years - more than 15 million years after the extinction of the dinosaurs.
Corrected entry: Shortly after returning from the time jump where history was altered, we hear a news report stating that fish are beaching themselves in large numbers. The problem with this is that earlier in the movie we learned that the last animal to be born in the wild was a crocodile, and a virus eliminated all other animals. Fish are different kinds of animals than crocodiles and lions, but they're still animals. There shouldn't be any fish left to be reported about, and the reporter's reaction to the story she is telling doesn't indicate shock that the fish are there at all, so they aren't there as a result of history being altered during the jump.
Correction: You've already corrected your own submission! As you state, "from the time jump where history was altered", you've already given the movie its perfectly plausible explanation about the fish. Not a mistake.
Corrected entry: The biggest mistake I see is the butterfly death changing anything at all. Isn't the place where the butterfly dies engulfed in volcanic ash anyway, killing everything anyhow? So how can the death of this butterfly affect anything, if in a matter of seconds after its death the whole place is destroyed by the volcanic eruption?
Correction: There was nothing to stop the butterfly flying away until it got stepped on, if you watch the film, you can see that the butterfly was already heading away from the direction of the volcano when it was killed, and however improbable it may appear, that is what the movie makers were intending to convey that it WOULD have survived.
Corrected entry: The waves that bring about changes - consequences of a different evolution - never really alter the human-made structures. The buildings are essentially all there, they are just covered with vegetation. The whole world should be changing along with the rest of the natural world.
Correction: Why? In the original short story, the changes meant a different president was elected and English was spelled differently. It's impossible to predict what could happen differently and the same over millions of years.
Correction: Just because no butterfly fossils were found from before said time doesn't mean they weren't around before said time. The fossils just didn't survive the test of time. Besides, since no one was around to document the fact that butterflies and dinosaurs never coexisted means that no one could, from a scientific standpoint, say they never coexisted.