twins fraternal

基本解释

The notion that the twins are fraternal symbolizes the union between the feminine and masculine aspects of yourself.
雙胞胎是你自己女性和男性方麪結郃的對偶標志。
But importantly, the chance of both twins being affected by autism was not low among fraternal twins, which is counter to what would be expected if genetics were the dominant factor.
但重要的是，在異卵雙胞胎中，兩個孩子同都患自閉症的概率也不低，如果基因因素是主要因素，那麽這種情況就與我們期望的結果是相反的。
The investigators then determined the differences in autism concordance rates between the identical and fraternal twins to estimate the contribution to autism of genes and of a shared environment.
研究者決定同卵和異卵雙胞胎自閉症一致幾率的區別，估計自閉症的病因是基因還是共享的環境。

This means that behavioural traits with a large genetic component are more likely to be shared by identical twins than fraternal twins.
ECONOMIST: Evidence that psychopaths are born, not made
They used the classic trick of neutralising the effect of upbringing and exposing that of genetics by comparing identical twins (who share all their genes) with fraternal twins (who share half).
ECONOMIST: Evolution
Conversely, those traits with a large environmental component will be shared by identical and fraternal twins in equal measure.
ECONOMIST: Evidence that psychopaths are born, not made