ANIMAL MIND

Greymouth Evening Star, 27 August 1931, Page 3

ANIMAL MIND

WHAT TESTS REVEAL. American psychologists have been active ih the study of Animal behaviour; but many of them, seeking rather the mechanical categories of explanation, have taken a very limited ‘view of the mental power of animals, writes Professor William MacDougall, the distinguished psychologist, in the “New York Tinies.” Their experiments have usually been so designed as to provoke behaviour that can be interpreted only in terms of rehexes and conditioned reflexes. I have felt strongly that we need to experiment in the opposite direction, Matiiely, to devise conditions in wiiicii the utmost intelligence of which an animal is capable may be brought out by intelligently directed activity. To this end I have taken a female raccoon eight months old, named Dee. Each day she is allowed to find her ; fo‘dd in a large wooden box. A lid is subsequently added, attached to the box by hinges, with one side of the lid projecting beyond the side of the box'.Dbe quickly learns to push up the ’lift and To slip under ft. to the food. A single wooden latch is then added. ft consists of a long slip of wood pivoted to the side of the box by a single screw and holding the lid fast by -means of a notch hooked over the -lip of the lid. Dee, seeking to life the lid, fitids it held fast, but she persists in more or less random fashion, pushing and pulling, until at last she manages to push against and move the ildtch. Whereupon she quickly raises the lid and secures her food. She soon 'becomes proficient in moving the latch bbfore lifting the lid. A second and similar latch is no v added, holding the first one and requiring a turn of 30 degrees or more before the first latch can be moved. Dee finds that the first latch resists her efforts to move it, and she falls back on her random pushing and pulljfig until the second latch has been moved. Then she quickly turns the 'first -latch and lifts the lid to get to ■her food. After a few repetitions of this .performance she turns first the second latch, then the first one before attempting to lift the lid. A whole series of latches is th™ fixed in a similar manner until there aro 24 in all. Making about six triads a day, Dee learns how to unlock the whole series of interlocking latches until, at the end, she moves the whole 24 before attempting to lift the lid.' frequently moving the whole series so rapidly that the eye can hardly follow jfeer movements . Another experiment , of a different kind has been made with Dee’s sister, Dum. Burn is tethered’by a light collar ard chained to a tree on a lawn, sb that she can range freely ih a circle twelve feet in diameter. A piece of food is placed at the rim of the circle sb that she can .rbacii it when, her (ffiain is extended, in a straight line, when Duin has become accustomed to receiving the pieces 6f Mod a post is thrust vertically into The ground, about three febt from the tree. If now, as Dum aproaches hfej- fobd, her chain becomes bent around the post, she cannot reach the bait. She clearly is actuated by a stronge impulse to reach the food because she is hungry, and scrambles vigorously at the end of her tether; but very soon she retreats from the bait, wanders U little, goes behind the post, and returns to seize the food, which she is how able to reach. On repetitions or the experiment she repeats her bo haviour many times with very little dfelciy. Up to this point the stake has been so placed that in order to free her chain Dum must go clockwise about it.. The stake is how pushed in the ground in such a way that she must go anti-clockwise to free her chain. At first shh goes clockwise and s > loops her chain around the stake. The task of reaching the. bait seems too difficult for her small mind, sb the stake is pulled up and reset. It -takes several experiments before Dum gathers that she must go anti-clock-wise to reach the bait.

A loop is notv made in the middle of the chain, and it is slipped over the stake, so that the bait is again just beyond her reach. She immediately goes to .the stake,’turns, this way and that.about it, but without success, peterminetl not to be baffled, how-

ever, she digs up the stake and so frees the chain that she can reach! the bait. . pu all subsequent experiments of this kind she goes first to the post and digs it up.