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Escape to Madagascar

Propithecus diadema, the diademed sifaka.  Credit: Mitchell Irwin

Propithecus diadema, the diademed sifaka. Credit: Mitchell Irwin

By Karen Samonds

Madagascar’s bizarre assemblage of fauna didn’t evolve from the fossils found on the island, so how did they get there?

Karen Samonds is a palaeontologist and Senior Lecturer in the School of Biomedical Sciences at the University of Queensland.

The full text of this article can be purchased from Informit.

‘‘For naturalists Madagascar is the true Promised Land. Nature seems to have withdrawn there into a private sanctuary, to work on models different from any she has used elsewhere. There you meet the most unusual and marvelous forms at every step . . . What an admirable country, this Madagascar!’’ Joseph-Philibert Commerson, 1771

The sun was hot, and my mind was off wandering again. Tired, and covered with sand and sunscreen, I looked again at the 40-million-year-old fossil bone protruding out of the side of the ancient cliff. Could it be the side of a crocodile vertebra? Maybe a dugong rib? Or, simply another fragment of non-identifiable turtle shell?

Slowly I scraped away at the surrounding rock hoping that it would reveal itself to be something truly spectacular. In fact, there are lots of tantalising things it could be as our current understanding of this critical time period in Madagascar – the past 80 million years – is virtually a blank slate. That’s a problem, because the early fossils we have found do not seem to have much to do with the bizarre assemblage of animals living on the island today.

So how did the current residents get there if they didn’t evolve from the fossils currently known? Did they walk or fly or float from the nearest mainland? That’s the question we set ourselves, and from our calculations based on the...

The full text of this article can be purchased from Informit.