Jennifer Vonk, a psychologist at Oakland University in Michigan who was not involved with the study, tells LiveScience that it's possible the turtles didn't make a connection between the touchscreen and the bowls but simply "had a preferred side."
The study authors, however, believe that the tortoises' correct choices indicate "an ability to transfer learning from the touchscreen to a 3-D test arena." As Wilkinson points out, "animals have to learn to navigate efficiently around their environment to locate food, sun spots and shelter." To do this, reptiles rely on the part of their brain called the medial cortex (which controls spatial behavior, similar to the area in our brain called the hippocampus). Comparing the way reptiles and mammals think, according to Wilkinson and her colleagues, can teach us how brains evolved to guide us to our sunny spots.