308 THE TREND OF THE RACE 
may take comfort in the fact that their claims to superiority 
are not without their champions. Indeed some of the papers of 
which Pearson is a joint author suggest that in some respects the 
first born may have an advantage over their successors. Beeton 
and Pearson in their investigation of the age at death of over 
1,000 pairs of sisters and brothers found that the earlier born had 
on the average a longer life. The ages at death were as follows: 
Elder Younger 
DISLELS isis dee eS des 59-924 55-667 
Brothers 22 ccseen ew ewswes 58.560 54-575 
The study was based on the longevity of adults who have 
reached maturity, thus eliminating the effect of infant or child 
mortality. In a study of 1,051 pairs of brothers and 733 pairs 
of sisters where it was possible to ascertain the interval between 
the births it was found that the. greater the interval the less 
is the expectation of life of the younger member of a pair. “A 
brother born ten years before another brother has probably 
seven years greater duration of life; a sister born ten years before 
another sister has about six years longer duration of life.” 
This conclusion is not exactly opposed, however, to the doctrine 
of the inferiority of the first born, especially at birth. As only 
adults were considered in Beeton and Pearson’s studies the 
earlier born had passed the first ordeals of life and their greater 
early death rate may have rendered them relatively more hardy 
than their less stringently selected younger siblings. 
In an article entitled ‘‘The Long-Lived First-Born” the editor 
of the Journal of Heredity presents a study of longevity accord- 
ing to birth rank of 802 individuals most of whom were over 90 
and all of whom were over 80 years of age. A relatively large 
number, 217 out of 802, or 27.05 per cent of first born children live 
to be aged; a smaller percentage of aged occur in the second born, 
118 out of 786, or 15.01 per cent and a still smaller percentage 
of aged occur in the third born, 104 out of 765, or 13.59 per cent, 
the succeeding birth ranks showing only a slight further decrease. 
