Not everyone has welcomed the arrival of Homo naledi, announced by Wits University professor Lee Berger to the world recently. One critic, University of Berkeley palaeontology professor Tim White, said it might not be a new species at all, but Homo erectus.Now Berger's co-author on the Naledi paper, University of Wisconsin-Madison anthropology professor John Hawks, has hit back at White and other critics.He has written on his blog: "We compared the Homo naledi fossils to every specimen available to us. Homo erectus is a very well-known species. Many of our team have studied the originals of most Homo erectus remains around the world, and I have personally examined the key cranial and postcranial specimens from Dmanisi in Georgia."So we examined this question [whether the fossil was Homo erectus] in great detail as we studied the Homo naledi material."Hawks said scientists concluded the fossil was of a previously unknown species.In response to criticisms that the announcement of Naledi was a rushed publicity stunt and science had collapsed into entertainment, Hawks said: "Some people have become jaded about the entire idea of hominin species, cynically concluding that every new species name is just an exercise in glorifying the discoverer, or is stoked by nationalist pride."In my experience, that's rarely true. Palaeoanthropologists are careful scientists who want their work to stand the test of public attention."Hawks attacked the critics, saying some did not have the power to make credible statements in the media."Some senior palaeoanthropologists have unfortunately been accustomed to secretive practices. They may think that people will trust their authoritative pronouncements about fossil remains because no one will ever see the data. That's an unscientific approach, and it leads to bad practices."Hawks encouraged people to print or review the data on Homo naledi themselves. He urged palaeontologists to follow his lead and share the data on their own discoveries."Of course, no one has to trust what we have written about the fossils, because we have made the 3D shape files for many of them [freely] available through MorphoSource.org. Anyone can sign up for a free login and download the shape files, even print them out."..