You know you have 46 chromosomes. If you're lucky, you've got 23 from each parent. Sometimes you get an extra one or drop one out, but -- so you can skip the grandparent and great-grandparent stage and go right to the great-great-grandparent. And you have 46 people and you give them a scanner, or whatever you need, and they look at their chromosomes and each of them says which one he likes best, or she -- no reason to have just two sexes
大家都知道我们有46条染色体。如果你幸运的话，你分别得到23条 从父母中；有时候你会得到额外的一条，或是少了一条， 你可以跳过曾祖父母和曾曾祖父母的阶段 直接到曾曾曾祖父母。那么现在总共有46个人 然后你给他们扫描器，或者你想要的选择 于是他们看著他们自己的染色体，每个人都说 哪一条染色体是他最喜欢的-