We now have the strongest indicator yet that there are two separate species of red panda: the Chinese red panda (Ailurus styani) and the Himalayan red panda (Ailurus fulgens).
我们现在有了迄今为止最强的指标，表明有两种不同的小熊猫：中国小熊猫(Ailurus Styani)和喜马拉雅小熊猫(Ailurus Fulkins)。
Previously, these were classified as subspecies based on the pandas’ physical characteristics and location, but this has been contested due to a lack of genetic evidence.
在此之前，根据大熊猫的物理特征和地理位置将它们归类为亚种，但由于缺乏遗传证据，这一点一直存在争议。
To address this gap, Yibo Hu at the Chinese Academy of Sciences in Beijing, and his colleagues sequenced the whole genomes of 65 red pandas by extracting DNA from blood, muscle and skin samples taken from museum specimens and red pandas in captivity.
为了弥补这一差距，北京中国科学院的胡一波和他的同事们从博物馆标本和圈养小熊猫的血液、肌肉和皮肤样本中提取DNA，对65只小熊猫的整个基因组进行了测序。
These red pandas came from wild populations living in the Himalayas in Nepal and India, or the Qionglai mountains in China’s Sichuan province.
这些小熊猫来自尼泊尔和印度喜马拉雅山或中国四川省琼莱山的野生种群。
Using data from 49 red pandas, the team compared their haplotypes, variations in DNA inherited from a single parent – for example, their mitochondrial DNA, which is inherited from the mother, and Y chromosomes, which are inherited from the father.
利用来自49只小熊猫的数据，研究小组比较了它们的单倍型、从单亲继承的DNA变异-例如，它们从母亲那里遗传的线粒体DNA，以及从父亲那里遗传的Y染色体。
Compared to Chinese red pandas, the Himalayan red pandas had 50 per cent fewer mutations in the single letters, or bases, that make up DNA across their whole genomes .
与中国小熊猫相比，喜马拉雅小熊猫在组成它们整个基因组的DNA的单个字母或碱基中的突变少了50%。
Hu’s team also found that the haplotypes clustered together in different regions of the genomes of Himalayan and Chinese red pandas, and there were no shared Y chromosome variants between red pandas from the eastern Himalayas and those from Sichuan.
胡的团队还发现，这些单倍型聚集在喜马拉雅和中国小熊猫基因组的不同区域，来自喜马拉雅东部的小熊猫和来自四川的小熊猫之间没有共同的Y染色体变异。
Hu says this shows that they genetically diverged from each other, with minimal transfer of genetic variation between the populations, resulting in the two species.
胡说，这表明它们在遗传上彼此分道扬镳，种群之间遗传变异的转移很少，导致了这两个物种。
This divergence happened about 200,000 years ago, he says.
他说，这种分歧发生在大约20万年前。
Physical differences between the two populations supported the classification – the Chinese red panda has redder fur on its face and more prominent tail rings, for example.
两个种群之间的身体差异支持了这一分类-例如，中国小熊猫的脸部毛发更红，尾环更突出。
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