Friday, June 21, 2013
Elephant Brains, Part 1
As more and more is becoming known about brains in general, I find it interesting to note reported differences as well as similarities between human brains and those of other creatures. Along with apes and sperm whales, the elephant has a large brain relative to body size. According to Katy Payne, “Brain size provides a rough measure of mental flexibility—some say intelligence—and large mammalian brains are associated with complex sociality.” Elephant brains, located at the back of the scull well away from the forehead, elephant brains are the largest in size of all land mammals. By comparison the human brain is larger in proportion to body size and is right behind the forehead. A new-born elephant’s brain is 35% of the mass of an adult brain; a new-born human’s brain is 26%. In adulthood, the weight of an elephant’s brain averages between nine and twelve pounds and makes up about 0.08% of total body weight. The human adult brain weighs three to four pounds and makes up 2.0% of total body weight. The elephant’s cerebellum is larger than that in the human brain. There is some speculation that the cerebellum's high degree of development may be related to the highly coordinated trunk movements. Indeed, the elephant uses its trunk as human’s use a hand. The trunk is able to carry a 600-pound log or pick up an object as small as a coin. Part 2 tomorrow.