Studies show that turtles may be exceptionally intelligent, especially tortoises. Even Charles Darwin thought they must have exceptional memories because they travel long distances between where they eat, sleep, and bathe. Other explorers discovered they could train tortoises.  Despite Darwin’s observations, many people thought turtles were stupid because it’s easy to collect them.  The Okinawa Institute of Science and Technology says that there is more evidence today than ever for tortoises’ intelligence. Dr. Tamar Gutnick has spent nearly a decade working with and observing giant tortoises.  Dr. Gutnick and her colleague, Dr. Michael Kuba trained six groups of tortoises. The researchers used positive reinforcement and gave them three tasks to learn, each one more difficult than the last.  The tortoises learned all three tasks easily, so the researchers took it a step further. They waited three months before asking the tortoises to perform the tasks again. Every tortoise immediately remembered the first and second task. The third was a bit more complicated, but with a little extra training, they relearned it.  Besides tortoises, turtles are highly intelligent creatures. They have survived for over 250 million years, so they must be doing something right. One study shows that turtles have better hearing, smell, and sight than they did millions of years ago.  Although turtles are not as intelligent as mammals, they learn through instinct and experience.