SCIENTIFIC STUDY OF TWINS

Hawera Star, Volume LIV, 2 March 1935, Page 11

SCIENTIFIC STUDY OF TWINS

Value of Careful Observation Urged by Doctor

IJUVINS would do a great public service if they submitted themselves to scientific observation, Mr J. A. Fraser Roberts suggested in a lecture at tlio Eugenics Society in London recently. “Twins as objects of study,” lie said, “are of incomparable value to science. It would be of the utmost value if physicians could make full notes of all twin births and if these could be recorded in some way. It is also to be hoped that the parents of twins will increasingly realise the great service they could render to the advancement of knowledge by allowing their children to be carefully observed.”

As regards mentality, it was shown that environment was' proportionately more important than it was iti the of physical characteristics. Nevertheless, twin studies also showed that heredity was more important than erivironriient iri determining mentality as measured by intelligence tests iri a group, living under ordinary coridi-. tions. If, however, environment conditions could be radically altered the relative importance, might be changed. Heredity might become either more of less important.

He suggested that later in life twins might submit themselves for scientific observation. He pointed out that there were twins which did not resemble each other any more than do ordinary brothers and sisters, and which might be of like dr unlike sex. They were called fraternal twins. Then • there were identical twins, which were always of the same sex and strikingly similar.

Fraternal twinning was to some extent hereditary. The production of iiiiiimmiiiiiiiiiitimiimimiiiiiiiimiiiMiiiiiiniiiitmiiJimiiiJ

such twins depended on the . mother .. < and not on the father/ though the. father might pass on the tendency, to his daughters. Identical twins were horn, because one individual had split" ~ into two at an early stage of develop- " “ merit. Both father arid mother were - indirectly responsible. Identical twins always belonged to the same' blood group, but fraternal twins only some-" times. The comparison between, idea- - tical and fraternal twins could be used to form soirie estimate of.the relative ... .. importance of heredity and environment in determining human characteristics. ; "