The evolutionary history of lions is opaque, as most of the sub-species that once roamed the Old World are now extinct. However new research,发表于BMC进化生物学，使用灭绝狮子的古代DNA将历史上的差距拼凑在一起。调查结果为狮子的过去提供了新的了解，并可能对如何保存未来的遗留物提供新的洞察力。

狮子曾经在世界各地漫游。直到最近，可以在非洲发现各种子种类，从印度次大陆，通过中东和现代希腊和土耳其的各种子种类。伦敦大英博物馆的游客可以看到来自亚述（现代伊拉克）的雕刻，最近由当地人民大规模的大规模狮子狩猎（见图）。可悲的是，这些狩猎和像他们这样的人，相当成功。随着人类侵犯其栖息地的增加，迫害导致撒哈拉以南非洲外面的狮子虚拟灭绝。亚洲狮子只能通过大约400人的小而高度濒危印度人口生活;撒哈拉以外的所有其他狮子都灭绝了。

These recent extinctions create problems for our understanding of the evolutionary history of lions. Such an understanding is desirable not just to satisfy our curiosity about these charismatic animals, but also to help focus efforts for conserving those lions that still remain. Yet samplingonly那些仍然存在的狮子群不可避免地给出了不完整的 - 并且也许误导 - 这种物种历史的印象。

那么，建议新的研究recently published在BMC进化生物学那why not use what remains of extinct lions to fill the gaps in their history?

Origins of the ancients

一个全球的研究人员，由此引领罗斯巴内特杜伦大学的搜索博物馆在欧元pe to locate bone or tissue specimens from extinct lions, in order to extract their DNA. Samples from extinct lions originally living in West, Central and North Africa, as well as some from the Middle East, were tracked down, of which a number had somewhat unusual origins. Two skull fragments from North African Barbary lions, now housed in London’s Natural History Museum, were originally found underneath the Tower of London during building work, presumably remnants of the Tower’s medievalRoyal menagerie。

从这些博物馆样品中提取线粒体DNA（MTDNA）并将DNA与来自非洲的现有狮子群体的先前公布的MTDNA序列组合使作者能够估计这些不同人群（古老和现代）的相关性以及可能的他们彼此分开的日期。

Consistent with previous analyses, the researchers find that the most likely origin of lions is eastern-southern Africa. What’s new is the estimated date for the migration of lions out of Africa and into Asia.

Previous research, based only on existing populations, suggested that this occurred at least 74,000 years ago and perhaps as long as 500,000 years ago. This new work suggests that the exodus of lions out of Africa occurred a mere 21,000 years ago. The additional use of ancient DNA from extinct populations has then resulted in substantially different conclusions from studies using living lions only.

Out of Africa

此数据还允许映射此迁移的可能课程。结果表明，在东非最初出现，狮子大约12万年前迁移到西非和中非;气候变化然后分开这两个人群。

The authors analysis suggests these western populations were the pioneers who migrated into North Africa and from there into Asia, Europe and the Middle East (see figure 3 for more details). Genetically then, modern day lion populations in West and Central Africa appear to be more closely related to existing Asian Lions (and all those now extinct populations in-between) than they are to East African lions.

Given that these West and Central African lion populations are close to extinction in the wild, this has potentially important implications for lion conservation. Currently, all African lions are considered to represent just one conservation unit, with Asian lions making up a second. The authors strongly suggest that this dichotomy now needs to be revised. Central and West African lions are actually more closely related to Asian lions and, to preserve as much lion diversity as possible, extra attention needs to be given to these populations. This research then, does not just change our perceptions of the lion’s past but may also change our perception of how to safeguard its future as well.

Ancient DNA comes of age

这些结果带有警告。所有这些发现都是基于母体遗传的线粒体DNA which, as the researchers readily admit, cannot be considered as accurate as phylogenetic analyses based on biparentally inheritednuclear脱氧核糖核酸。这是狮子等物种的特别关注，在那里迁移人口之间的男性，而女性通常留在母亲的群体中。

当然，使用MTDNA的原因是它更容易从骨碎片等困难样本中成功提取而不是核DNA。也许在未来的下一代测序技术将使核DNA从这种样品中提取有足够的质量来证实作者的结果。即使没有这种确认，它仍然是非常非凡的，我们可以追溯到过去，利用动物的DNA死亡多世纪，其整个亚种不再在地球上的任何地方发现。古代DNA研究有可能解释过去的多样性，也许可以帮助我们为未来保存它。