A month or so ago I noticed this interesting article in the weekly Guardian. It's about some bones  found in Indonesia in 2003. The bones are very small so the group that found them believed them to be from new species Homo floresiensis. This was disputed by another group of scientists who claimed the bones where from a modern man with Down's syndrome, they published a paper to that effect in the Proceedings of the National Academy of Sciences (PNAS). All science journals commission independent experts to check submitted papers, a process known as peer review, one of the big strengths of the scientific method. However as members of the National Academy of Science the authors of the Down syndrome paper were allowed to select their own reviewers, their paper was therefore published without a proper independent peer review. Worth mentioning when talking about peer review that it isn't always done properly.