yellow bellied marmot

The yellow-bellied marmot (Marmota flaviventris)

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A KEY sign of ageing slows right down when marmots are hibernating. This suggests we might be able to induce similar changes to put humans in suspended animation for long-distance space travel. “They may not age during this process,” says Gabriela Pinho at the University of California, Los Angeles (UCLA).

Pinho has been studying wild yellow-bellied marmots – a kind of ground squirrel – in Colorado. These animals hibernate for up to eight months a year, dropping their body temperature as low as 5°C.

Starting in 2004, Pinho and her …