Modern mtDNA studies of bone remains has determined that the Cylindraspis species were all descended from one species that colonised Mauritius from Madagascar by sea, many millions of years ago. The population on Mauritius differentiated into both Saddle-backed and Domed species, and the ancestors of the Saddle-backed species (Cylindraspis inepta) then colonised Rodrigues (where they once again differentiated into both Saddle-backed and Domed species) and later Réunion, the most recently formed island.
Human settlers colonised the Mascarenes in 1663. These giant tortoises were very large and slow, thus making them easy game. Like many island species they were also reported to have been friendly and unafraid of humans. Most species of this genus were already driven to extinction by 1795 and the last individuals were reputed to have died around 1840 (Arnold 1979, Bour 1980, Cheke and Hume 2008).
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