That's another easy one. Speciation has been observed on any number of occasions. How about if I provide an example of speciation that has all of the transitionals (that creationists claim do not exist) still in place?
Ring species provide unusual and valuable situations in which we can observe two species and the intermediate forms connecting them. In a ring species:
- A ring of populations encircles an area of unsuitable habitat.
- At one location in the ring of populations, two distinct forms coexist without interbreeding, and hence are different species.
- Around the rest of the ring, the traits of one of these species change gradually, through intermediate populations, into the traits of the second species.
A ring species, therefore, is a ring of populations in which there is only one place where two distinct species meet. Ernst Mayr called ring species "the perfect demonstration of speciation" because they show a range of intermediate forms between two species. They allow us to use variation in space to infer how changes occurred over time. This approach is especially powerful when we can reconstruct the biogeographical history of a ring species, as has been done in two cases. Source
Additional information from the same source (footnotes omitted and emphasis added):
Ensatina salamandersOne well-studied ring species consists of salamanders in the Ensatina eschscholtzii group, distributed in mountains along the west coast of North America. In 1949, Robert Stebbins described a fascinating pattern of geographical variation in these salamanders:
- Two distinct forms of Ensatina salamanders, differing dramatically in color, coexist in southern California and interbreed there only rarely.
- These two forms are connected by a chain of populations to the north that encircles the Central Valley of California, and through this ring of populations the color patterns of the salamanders change gradually.
Stebbins thought that this situation arose when an ancestral population of salamanders, in northern California, expanded southward along two fronts, one down the Sierra Nevada mountains, and the other down the coastal mountains. The two groups gradually became different as they moved south. When they met again in southern California, the two expanding fronts were so different that they rarely interbred, and were therefore different species. More recently, a team of researchers led by David Wake has examined genetic relationships among salamander populations using DNA sequences and other molecular traits, and the genetic evidence has supported Stebbins' hypothesis. The geographical variation, when combined with the inferred history revealed by the molecular traits, allows us to envision the small steps by which a single ancestral species in the north gave rise through evolutionary divergence to two species in southern California.
You are batting .000 so far. Try again?
Your examples cite variations of a species of which there is no argument and plenty of evidence. There is no evidence in science of creatures jumping from one species to another which is absolutely required for evolution to be true. It is therefore certainly easy to maintain that there is not one shred of scientific evidence of a fish becoming an animal or of a monkey becoming a man.
Next.