RTFA: http://www.sciencedaily.com/releases/2008/05/08050…

An analysis of the genome, published today in the journal Nature, can help scientists piece together a more complete picture of the evolution of all mammals, including humans.

The platypus, classified as a mammal because it produces milk and is covered in a coat of fur, also possesses features of reptiles, birds and their common ancestors, along with some curious attributes of its own. One of only two mammals that lays eggs, the platypus also sports a duck-like bill that holds a sophisticated electrosensory system used to forage for food underwater. Males possess hind leg spurs that can deliver pain-inducing venom to its foes competing for a mate or territory during the breeding season.

“The fascinating mix of features in the platypus genome provides many clues to the function and evolution of all mammalian genomes,” says Richard K. Wilson, Ph.D., director of the The Genome Center at Washington University and the paper’s senior author. “By comparing the platypus genome to other mammalian genomes, we’ll be able to study genes that have been conserved throughout evolution.”

The platypus represents the earliest offshoot of the mammalian lineage some 166 million years ago from primitive ancestors that had features of both mammals and reptiles. “What is unique about the platypus is that it has retained a large overlap between two very different classifications, while later mammals lost the features of reptiles,” says Wes Warren, Ph.D., an assistant professor of genetics, who led the project.

Comparison of the platypus genome with the DNA of humans and other mammals, which diverged later, and the genomes of birds, whose ancestors branched off an estimated 315 million years ago, can help scientists fill gaps in their understanding of mammalian evolution. The comparison also will allow scientists to date the emergence of genes and traits specific to mammals.

Things are getting crazy. This article includes a link to the raw DNA data. I find that fact, by itself, to be insane. …not to mention the fact that this is an insight into the craziest “mammal” in existence: the platypus.