Most of the human characters whose inheritance can be studied fon a large scale are quantitative and apparently continuously varying characters such as stature, length of forearm or cranial Index.' So far it has not been possible "to analyze these with the aid of the Mendelian Jaws but definite correlations have been found by statistical methods, might be claimed. that post-natal environmental factors play here an important role, but experience has shown that characters such as eye: colour which are not influenced by environment, show the same. cor relations.
When brothers and sisters are com pared regarding psychological characters, such as success at school, intelligence quotients, quick temper, and so on, the same extent of cor relation is found as. in. physical charseters. "Again the question arises how far this resemblance' is due to similarity of environment and how far to heredity.
Generally speaking, the obser vations carried out #0 far speak in favour of heredity. For instance, attempts to correlate among. school children intelligence with economic and other environmental conditions showed very small correlationcoulficients, Interesting observations have been made upon "identical" twins, formed from the same fertilized egg and therefore genetically identical. It separated at birth their intelligence quotients resemble one another to a very great extent but their emotional Fezetions and moral character differ markedly, Mixtures Mefore Ilstorieal Times. will be seen that as in animals so in man the problems of heredity are rather Involved. Our difewlties still increase if we try to deal not with individual families but with whole racial groups. For there are few questions, besides that of race, where even people with otherwise poised judgment are so apt to be misled by prejudices. Yet a study of the skeletal: remains-of fossil man shows that. blending of divergent stocks was taking place lonia before historical times. The diffe aborigines with backward - culture still existing also show much mixing, of stocks and cultures.
Even on elementary study of history convinces us that some of the most progressive peoples. of Europe are the result of. repeated amalgamation. An authority, like E.B, Router, states in this" con~ nection that lone continued has been, this Giverte' have been "te ethnic clement rostinas ona a fusing to Mie ree Hee hing see ase a Satin Paha anita 9 Tong," time' ting the storia period such amalgamation nirntad ite stenion Gecated the people showed no conspicuous outwSra" tarente ye" problem Became more "sere when the mest Givers Sand" invented Soe tnleaion between Surope andthe Easton the one hand the, Amoreans othe other made possibi ree fine emalgaraton bowen markedly diferent rac groupe he rest tetht large groupe of hybrids Rave Become ""evetope." Who "who Pioneers in"Nortn" America into mingled ona vast cele ith the india 20th some tries there fearn 90 dnduiduse't pure lain esr whi gits the Breeds "outnumber the pure noc Much intermingling with Indians ann ook place the Spith and Portage" sooner of tha" West Mui Conta and South Amen Simisriy numerous. mute" pros fence rest whenever white Bigrants came "in conse with Rorocs, sich as" inthe Unod Site andthe Wea indies, "thre are variout® soci haueeata freups in Brian india of welt Steere tthe Oren
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