Every Link Is A Missing Link --

until it's found. That's the lesson to be learned, not from the discovery of Australopithecus sadiba, but from media hype (and it's rather sad that that's the best you can say about science reporting in the popular press).

The term missing link is misleading. Any fossil that shows characteristics of two or more documented species is called a transitional. There are great examples of transitional fossils for whale, horses, and of course people, as well as less visible lineages among invertebrate animals, plants, and microbes.

The classic example of a transitional fossil (so much so that I'm surprised that Steven Andrew, the author of the above paragraph, didn't mention it) is, of course, Archaeopteryx, discovered only a couple of years after the publication of On the Origin of Species. I actually take that one as an indicator of the validity of evolution, maybe not so much when it was discovered, but certainly now -- we know that birds have anatomic features in common with one group of the dinosaurs, the Ornithyschia, and there is living proof -- after a manner of speaking.

The rest of Andrew's article is a nice summary of the transitional fossils from Australopithecus to Homo -- certainly worth a read to brush up.