> An interesting recent paper shows that the non-inherited genetic material of the parents may _still_ have an influence on the kid. [0] Yes, but that comes o

> An interesting recent paper shows that the non-inherited genetic material of the parents may _still_ have an influence on the kid. [0] Yes, but that comes out of the heritability component, not the non-sharedenvironment component. > For example: birth order, number of same-sex siblings etc. Birth order, by definition, can't explain any of the variance in fraternal vs identical twins, and there's a lot of doubt about whether it exists at all and for which traits. Likewise, I haven't seen much credible research on sibling effects - most such sociological research doesn't even bother to try to control or quantify any of the relevant genetics, and is 100% useless.