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First things first: The hyrax is not the Lorax. And it does not speak for the trees. It sings, on its own behalf.

The hyrax is a bit Seussian, however. It looks something like a rabbit, something like a woodchuck. Its closest living relatives are elephants, manatees and dugongs. And male rock hyraxes have complex songs like those of birds, in the sense that males will go on for 5 or 10 minutes at a stretch, apparently advertising themselves.

One might have expected that the hyrax would have some unusual qualities — the animals’ feet, if you know how to look at them, resemble elephants’ toes, the experts say. And their visible front teeth are actually very small tusks. But Arik Kershenbaum and colleagues at the University of Haifa and Tel Aviv University have found something more surprising. Hyraxes’ songs have something rarely found in mammals: syntax that varies according to where the hyraxes live, geographical dialects in how they put their songs together. The research was published online Wednesday in The Proceedings of the Royal Society B.

Bird songs show syntax, this ordering of song components in different ways, but very few mammals make such orderly, arranged sounds. Whales, bats and some primates show syntax in their vocalizations, but nobody really expected such sophistication from the hyrax, and it was thought that the selection of sounds in the songs were relatively random.

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Hyraxes are common in Africa and the Middle East, and there are quite a lot of them where Mr. Kershenbaum lives. He kept hearing their songs and thinking, “I simply don’t believe that these complex songs can be totally random.”

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So he and his colleagues recorded hyraxes around Israel and analyzed the makeup of the songs using mathematical techniques drawn from genetic analysis. They found a complex syntax that did vary. They suspect that the dialects may be carried by males when they leave their home territory as they mature, and that changes in dialect come as other hyraxes copy the songs imperfectly or improvise.