这些部分的特征让古生物学家得以作出这样的结论:这种动物在哺乳动物谱系中,与有胎盘类的关系较与有袋类(如袋鼠)的关系更接近。
These features led the paleontologists to conclude that the animal was closer to living placentals on the mammalian family tree than to pouched marsupials, such as kangaroos.
科学家们同意DHA在怀孕的后半期会自然地通过胎盘传输给胎儿,可能对视力和大脑发育有好处。
Scientists agree that DHA, naturally transmitted to a fetus through the placenta in the last half of pregnancy, is important, probably to visual and brain development.
之后的五千万年内没有任何新奇的事发生,就在这时,胎盘哺乳动物(或者说是那些有后代存活的哺乳动物)突然之间分化为四种所谓的生物总目。
Nothing much then happened for 50m years when, all of a sudden, the placentals (or, at least, those with surviving descendants) split into four so-called superorders.
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