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Reptiles known as ‘living rocks’ show surprising cognitive powers

90 year old Aldabra tortoise "George" and experimenter Tamar Gutnick at the Vienna Zoo.

Experimenter Tamar Gutnick with George, a 90-year-old Aldabra tortoise who was schooled to follow a toy of a particular colour. Credit: Michael Kuba

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Nature 576, 10 (2019)




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