featured image: A gorilla using a stick possibly to gauge the depth of water
A rough measure for comparing the intelligence of different animals is the ratio of the weigh to the brain to that of the spinal cord.
Such a ratio for a cat if four to one; for a monkey eight to one; and for a human being fifty to one. After man, the animal with the highest ratio is the marmoset, a South American monkey, with the ratio eighteen to one.
Among mammals, primates (humans and monkeys) are the most intelligent followed by flesh eaters and grazing animals.
But, like human beings, individual animals can be brighter than their fellows. For instance, Johnnie, a rhesus monkey kept by Mr. Lindsay Schmidt on his farm at Balmoral in Australia, learnt how to drive a tractor and to follow simple driving instructions such as “turn right” and “turn left”.
Monkeys can also teach each other. Japanese scientists lured a troop of macaques to a supply of sweet potatoes. It was the monkeys’ habit to remove sand sticking to the vegetable by rubbing it before consumption. One of the monkeys, however, found it more effective to just wash the potatoes in a brook nearby. This practice soon spread, with the other monkeys following suit.
Other monkeys have learnt that the easiest and quickest way to separate grains of wheat from dust and sand is to throw handfuls of the dirt on to a stream or pond, and wait until the wheat grains float to the surface.
Among other animals with high levels of intelligence are dogs, horses, lions, tigers, and of course, elephants. Their ability to learn can be seen from the tricks they perform in the circus.
That being said, I hate making animals perform in circuses, where their intelligence is manipulated to perform tricks just so that the few people watching could enjoy momentarily. They don’t deserve such treatment.
However, many animals display a level of intelligence that humans find hard to believe.