It's to rise again. The animals can easily lose their bale de and fall on their back, where they are vulnerable to exposure. Tortoises are sustainable, being unable to flip themselves by twisting their bodies inside their shell. Dr Golubovic and her partners analyzed 118 tortoises(54 females and 64 males), placing each on pe on their back and then measuring how much they spent furiously waving their heads, legs and tail. Then they compared the tortoises performances with the geometry of their shell. The analysis needed to be more comprehensive than first supposed. They also needed the body temperatures of the tortoise.
The tortoises are gold blooded and might have struggled to have the energy to flip the selfs back over.