So this is a strange connection between two papers recently published. I so wish we had Hippo MC1R. If you don't know, MC1R is involved in pigmentation, but I am not so interested in the pigmentation of Hippo's more their phylogenetic relationship to Cetaceans. In a recent paper, or rather comment on a previous paper Jonathan H. Geisler & Jessica M. Theodor are debating between two phylogenies: ((Pig,Hippo),whale) or (Pig,(Hippo,Whale)) and are using a number of data points (fossil, morphology, and genetic) to get at the question. What's at stake, the ancestral aquatic characters being derived separately in whales and hippos or being shared derived characters inherited from a common ancestor.
They conclude (along with previous understanding as mentioned in Jerry Coyne's new book) that (Pig, (Hippo, Whale)) is the most parsimonious. This is challenged in a commentary (a response from those who originally published the (Pig,Hippo) connection). Both groups conclude that the extinct raoellids are the closest relatives to cetaceans but they disagree on the relationship between pigs, hippos and whales. They are dealing with a problem of homoplasy or convergence in the data.
Later this week I came across another paper examining Ungulate/Cetacean phylogenies using MC1R I was shocked to see no hippo in the data set or on NCBI. Someone should should totally sequence it just to satisfy my curiosity. Especially because the Nature paper is complaining of homoplasy and the MC1R paper is concluding that MC1R is great for mammalian phylogenies because it has such great resolution at so many taxonomic levels not to mention interesting information about pigmentation evolution. I know there are other studies out there but this seems like a good candidate gene to get at the pig, whale, hippo question, its unfortunate they were not sequenced along with all the artiodactyls and whales.
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