Humans living at high latitude have bigger eyes and bigger brains to cope with poor light during long winters and cloudy days, UK scientists have said.
The Oxford University team said bigger brains did not make people smarter.

The scientists measured the eye sockets and brain volumes of 55 skulls from 12 populations across the world, and plotted the results against latitude.
Lead author Eiluned Pearce said: "We found a positiverelationship between absolutelatitude and both eye socket size and cranial capacity."

The skulls were from indigenous populations ranging from Scandinavia to Australia, Micronesia and North America.
The largest brain cavities came from Scandinavia, while the smallest were from Micronesia.
"Barn owls are nocturnal hunters, they are also getting bigger brains." said Pearce.
The work indicates that humans are subject to the same evolutionary trends that give relatively large eyes to birds that sing first during the dawn chorus, or species such as owls that forage at night.
Co-author Prof Robin Dunbar said: "Humans have only lived at high latitudes in Europe and Asia for a few tens of thousands of years, yet they seem to have adapted their visual systems surprisingly rapidly to the cloudy skies, dull weather and long winters we experience at these latitudes."





据英国广播公司7月27日报道：英国科学家表示，住在高纬度的人眼睛和脑部会更大，原因是这里冬季和阴天的时间较长，人们要应对较暗光线所致。
牛津大学的研究者们说，脑部更大并不能使人更聪明。
科学家们通过测量来自全世界12个种族的55个头颅的脑容量和眼窝大小，得出其大小确实和纬度有关结论。

领头研究员皮尔斯说："我们发现纬度的高低和眼窝及头颅的大小成正比。"

这些头颅来自于包括斯堪的纳维亚地区、澳洲、密克罗尼西亚（西太平洋群岛）以及北美地区的土著人种。
来自于斯堪的纳维亚的头颅最大，最小的来自于密克罗尼西亚。
皮尔斯说："仓鸮（一种鸟类）是夜间捕食者，所以它的头颅也很大。"

这说明，和这个在黎明鸣叫最早的鸟类或其他诸如猫头鹰等在夜间捕食的物种的大眼眶一样，人类也遵循同样的进化趋势。

该研究另一位作者罗宾•邓巴教授说："人类在欧洲或亚洲的高纬度地区居住不过几万年时间，然而他们的视觉系统迅速地适应了高纬度的多云天气、阴冷的气候和漫长的冬季。"

• absolute [´æbsəlu:t] a.绝对的 n.绝对 (初中英语单词)
• chorus [´kɔ:rəs] n.合唱；齐声 v.合唱 (初中英语单词)
• latitude [´lætitju:d] n.纬度；地区 (高中英语单词)
• oxford [´ɔksfəd] n.牛津 (高中英语单词)
• positive [´pɔzətiv] a.确定的 (高中英语单词)
• relationship [ri´leiʃənʃip] n.关系；联系；亲属关系 (高中英语单词)
• relatively [´relətivli] ad.比较地；相对地 (高中英语单词)
• species [´spi:ʃi:z] n.(生物的)种，类 (高中英语单词)
• socket [´sɔkit] n.窝，穴，孔；插座 (英语六级单词)
• forage [´fɔridʒ] n.饲料 v.搜寻(粮草) (英语六级单词)
• surprisingly [sə´praiziŋli] ad.惊人地；意外地 (英语六级单词)