There is a great deal of evidnce FOR evolution.....
but the time scales are not to some people's satisfaction.
Speciation has been observed. The problem is that looking t the creatures, it is not readily seen that the two species are all that much different. That is what evolution states.
1: A genetic "bottleneck" occurs where t group of a particular species breaks off and is isolated. This could be Punc-Eek, it could be massive die offs from global changes.
2: Changes that occur in this small population are passed on more rapidly than in a larger population.
3: At some point, the "daughter species" will no longer be capable in interbreeding with the original species.
This will take generations to occur and even if someone sees it, they may not rcognize anything had happened at all.