50 Years ago

Under New Zealand conditions of sheep-farming, incisors of grazing sheep wear much more rapidly on improved pasture, chiefly ryegrass (Lolium perenne) and white clover (Trifolium repens), than on the finer native pastures of low carrying capacity. The cause is not nutritional in the generally accepted sense, however. It would rather seem that certain substances in the herbage of 'improved' pastures dissolve the teeth, the process being aided by the abrasive action of the plant fibre. Wear is also increased in mouths with certain undesirable anatomical characteristics which appear to be hereditary in origin.

From Nature 16 January 1960.

100 Years ago

The Family and the Nation: a Study in Natural Inheritance and Social Responsibility. By W. C. Dampier Whetham, F.R.S., and Catherine Durning Whetham — It is the duty of preachers of eugenics, a duty conscientiously undertaken by the author ... to educate public opinion in such a way that, aided by the legislation that will then be possible, it will insist on the more rapid multiplication of the desirable components of our society, and aim at the elimination of the rotten parts which now permeate it ... It is a well-known fact that the birth-rate in Great Britain fell from 36 per 1000 in 1876 to 27 per 1000 in 1907. This in itself may give cause for alarm, but the most serious feature of the fall is that it has not been the same in all classes ... As it is, the lowest stratum is as prolific as before, therefore our birth-rate has become selective. The least valuable portions of the population are selected to produce a disproportionately large share of the next generation, by the action of the more valuable portions in bringing about at any rate a partial self-elimination.

From Nature 13 January 1910.