What is clear is that the more scientists look, the more examples of convergence they find. Sometimes the reasons for a particular convergence are easy to parse. Consider the shared traits of the world's manifoldanteaters. For moving that long tongue in and out rapidly, a muzzle improves the aim. And it is best for the snout to be hairless, to make sure that the pincered ants and termites have nothing to grab onto.
Ants live in soil and sand, which requires powerful claws for digging.
There is need of a digestive system that can readily pass the sand and dirt that will be lapped up with each tongueful of food, and that can metabolize the blistering chemical defenses with which ants and termites are loaded. Finally, sand grinds down enamel, so teeth can be dispensed with altogether. And the ultimate proof is sitting on his desk, in the form of a newly issued Beanie Baby toy with a telltale tubular schnoz. Even the Beanie Baby phylogeny now has an anteater in it. Other cases of convergence are not so readily explained.