Monday, January 21, 2008

Mammals one is unlikely to encounter in British Columbia: Hyraxes.

More animal art. Why hyraxes? Because hyraxes are an interesting group. They are members of a branch of what has got to be one of the strangest clades (all descendents of a given common ancestor) in all of extant Mammalia.

First off, what they are: rabbit- to small dog-sized herbivores, five species in three genera more or less, endemic to Africa, the Arabian Peninsula and the Middle East as far north as Lebanon and Syria. They like rocky areas, the sorts of places one would expect to find a pika in this province, and are known for basking in the sun.

Now hold onto your hats. Guess what their nearest living relatives are.

Yes, you are correct. Proboscideans (elephants) and Sirenians (manatees, dugongs, and all that gang), a relationship long-suspected because of similarities in dentition. Whether hyraxes are the sister-group of the sirenians, or of a sirenian-proboscidean clade depends on which molecular data are analyzed and how, but there seems to be consensus that the three groups together form a monophyletic group, known as the Paenungulata.

Hyraxes, at least some species, are able to adapt to human environments. If you live in Hyrax territory, you may discover them lounging on your deck chairs. I find that charming.

I also find manatees charming. Elephants I appreciate, but sorry, no, their charm has been quashed by familiarity, and all that baggy-pantsed trumpeting.

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