Slow and wise: Test shows that animals – which are postcards of islands in the Pacific and the Indian – remember events that occurred until ten years ago.
13 Dec 2019, 12:09
Giant tortoises like the one in the picture above were one of the sailors' favorite meals until the 19th century. They were not easy prey because they were not prey at all: no need to kill them during capture. Just take a portion of the live animals on the ship and kill them one by one before preparing lunch. Far better than eating rotten meat after weeks stored without refrigeration.
Thanks to these and others, these chubby reptiles have earned a reputation for being slow and dumb. But not every ship carried hungry sailors. Some also carried shy playboys on track. This was the case of the British Charles Darwin. During the voyage of the HMS Beagle, he realized that turtles in the Galapagos archipelago traveled long distances between places where they slept, ate and bathed in mud – a sign that they had an effective memory of guiding them daily through the geography of the islands.
The crew themselves were not fools, and they became fond of the bugs. It was possible to train them like dogs to stay in one place without moving.
Ten years ago, Tamar Gutnick, then a master's student at Hebrew University, began working with the giant tortoises from the Vienna Zoo in Austria, which comes from the Galapagos and also from the Aldabra Atoll in the Indian Ocean. “When I first met the turtles, I immediately fell in love with them,” said Gutnick in a statement. “It was clear to me that they had distinct personalities – they were often bold.”
To test the turtles' memory, the first step was to train them to catch a colorful ball with their mouths. The ball stuck in the end of a toothpick. Then the ball was placed one or two meters away from the animal, and he was encouraged to move to bite it. Finally, Gutnick chose a different ball color for each turtle – and taught them to choose, when various options were offered, just the correct color ball.
Three months later, the turtles successfully performed the first two tasks. In the third task, five out of six remembered which color to bite faster than they had taken in the original training. Sign that there is at least one memory residue. Some turtles were tested nine years after the dressage section and were still successfully biting the balls. For those who live more than 150 years, nine seems to be little.