经济学人:进化生物学:古人类异血缘交配的证据 (2)(在线收听) |
Furthermore, the fossil had Neanderthal mitochondrial DNA. This is passed from mother to child, 此外,化石中有尼安德塔线粒体DNA。这是从母亲基因中遗传下来的, which meant that either the teenager was the daughter of a Denisovan father and a Neanderthal mother 这意味着这个少女要么是一位丹尼索瓦父亲和一位尼安德特母亲的女儿
or had come from a population with an extensive mix of traits, and had been born to parents who were, in effect, hybrids. 要么是来自于广泛性状相结合的一个群体,并且她的父母其实是混血。
Biologists know that animal populations of mixed ancestry 生物学家知道那些没经历过什么进化变异的混血动物种群,
who are undergoing little evolutionary change show signs of this equilibrium in their genes. 它们的基因中就有这种平衡的迹象。
Drs Slon and Paabo looked for just such markers in the genes of their Denisovan teenager and found none. 斯隆和派伯并没有在丹尼索瓦少女的基因中发现这种标记。
That ruled out the idea that she came from mixed ancestry. 他们排除了这位少女来自混血家族的想法。
They did, though, find that each chromosome pair the girl carried had one chromosome that was entirely Neanderthal in origin 虽然他们确实发现在女孩基因染色体对中有一个染色体完全属于尼安德特人;
and one that was almost entirely Denisovan. This signified that she had one parent from each group. 另一个染色体基本完全属于丹尼索瓦人。这表明她的父母分别来自这两支。
Knowing that the mother was a Neanderthal from the girl's mitochondrial DNA, means that her father must have been a Denisovan. 从这位少女的线粒体DNA中,我们知晓她的母亲是尼安德特人,这意味着她的父亲一定是丹尼索瓦人。
The 2013 analysis of the Denisovan fossil also showed interbreeding, albeit of a more distant sort. 2013年对丹尼索瓦人化石的分析也表明是异血缘交配,虽然这一支系更加遥远。
Add in this latest research, and although Neanderthals and Denisovans may not have met very often, 再加上这个最新的研究,虽然尼安德特人和丹尼索瓦人并不经常见面,
sex between them is likely to have been more common than was previously realised. 但是他们之间的交配可能比我们之前所认为的更加普遍。
The implication is that modern humans are likely to have a messier genetic heritage than once thought. 这表明现代人类的遗传遗传比我们曾经以为的更加混乱。 |
原文地址:http://www.tingroom.com/lesson/jjxrfyb/jjxrkj/457561.html |