Just before Christmas I was inspired by a post by Jon Tennant on his blog, To bird or not to bird… about whether anyone knows whether Archaeopteryx lithographica is a bird or not a bird. Amongst palaeobiologists and biologists Archaeopteryx is the poster organism for evolution and if you’ve ever been to a natural history museum you’ve undoubtedly walked past a cast or two, it is after all one of our Bingo! animals. It was the first fossil that really enshrined the ideas about evolutionary change. Ever since it’s discovery in 1861 (although Archaeopteryx fossils were discovered before then but not recognised as such) it’s almost a rite of passage for palaeontologists to have a ponder or even publish trying to work out the affinities of the animal. Is it a bird? It’s probably not a plane. Is it a reptile? Is it a dinosaur? (and yes smarty pants I know you can be all three).
The scientific techniques used to work out the affinities of animals only known from fossil remains have developed greatly over the last 150 years yet the answer to this question still seems far from being resolved. (more…)