BRAINS EXCHANGED.

Auckland Star, Volume LXVII, Issue 139, 13 June 1936, Page 9 (Supplement)

BRAINS EXCHANGED.

SCIENTIFIC EXPERIMENT.

FROGS ACT HKE TOADS.

A BIOLOGICAL PROBLEM.

Dr. H. G iceberg, of the University of Breslau's Zoological Institute, has been switching brains in toads and frogs with results that have aroused a lively discussion among the German biologists. Parts of brains of the European cross toad (Bufo* ealamita), the common, toad (Bufo vulgaris), and the European spadefoot toad (pelobatcs) on the one hand, and parts of brains of the European edible frog (Rana esculenta), the European moor frog (Rana arvalis), and the European tree frog (Hyla) on the other, were exchanged in the tadpole stage by a very delicate surgical operation. Only two animals survived and grew up.

The survivors were moor frogs which had received brain parts, of spadefoot toads. One moor frog had the middle and after brain, and the other moor frog the frontal brain of a spadefoot toad. Both creatures died after a year.

Frog No. 1 (with the new middle and after brain) seemed to have acquired inst.incts that did not belong to his species. He was forever trying to dig and thus behaving more like a spadefoot toad than a moor frog. He hopped little but crawled like a toad. One day he even dug a deep pit in a moist sand — something of which a moor frog is supposed to bo incapable.

Giesberg himself points out that the digging instinct wf this frog is by no means eo we'll defined as in spadefoot toads, which lie buried all day long. Ho thinks that the frog in the moor frog is still able to assert itself despite its toad's brain. A toad with the brain .of a tree frog would be unable to climb simply because of its anatomical structure, even if the tree-frog .impulse were present.

The alien brain is hindered from giving expression to its activity not by the sense organs, muscles and nerve centres, but by the reaction of the periphery on the center of the brain. In other words, it is not the brain impulse that modifies physical movement, but physical movement that modifies the brain. Put a toad's brain in a frog's body and the frog's body will change the toad's brain. That is the accepted theory. It explains ivhy the toad's brain is unable to make the frog move wholly as if it were a toad. '