If you are not satisfied with the shape of your nose, blame it on climate, not your parents or grandparents.

对自己的鼻子形状不满意？不要怪父母或祖父母，怪气候吧。

In a study published this week in the journal PLOS Genetics, researchers from the Pennsylvania State University found that human noses may have been shaped, at least in part, by a long process of adaptation to local climate conditions.

美国宾夕法尼亚州立大学的研究人员发现，人类鼻子的形状至少部分是由当地气候长期塑造而形成的。这项研究本周发表在美国《科学公共图书馆•遗传学》杂志上。

Generally, wider noses are more common in warm and humid climates, while narrower noses are more common in cold and dry climates, it said.

大体上，温暖湿润地区的人鼻子较宽，而寒冷干燥地区的人鼻子较窄。

The findings were based on an examination of the size and shape of noses on people with West African, South Asian, East Asian, or Northern European ancestry².

研究人员分析了西非、南亚、东亚、和北欧血统的人鼻子的大小与形状。

The researchers looked at the width of the nostrils³, the distance between nostrils, the height of the nose, nose ridge⁴ length, nose protrusion⁵, external area of the nose and the area of the nostrils by using 3D facial imaging.

借助3D面部成像技术，研究人员观察了鼻孔宽度、鼻孔间距离、鼻子高度与鼻梁长度、鼻子突出程度、鼻子外部区域、和鼻孔区域等。

It showed that the width of the nostrils is strongly correlated with temperature and absolute humidity, but not the result of a random⁶ process called genetic¹ drift.

结果显示，鼻孔宽度与被称为基因漂移的随机过程无关，而与温度和绝对湿度等气候特征强相关。

One purpose of the nose is to condition the air that we breathe, to ensure that it is warm and moist when it reaches the lungs, which helps to prevent infections.

鼻子的一个功能是调节吸入的空气，让空气在进入肺部时变得温暖、湿润，帮助预防感染。

The current study found the narrower nostrils seem to alter the airflow so that the mucous-covered inside of the nose can humidify and warm the air more efficiently⁷.

目前的研究发现，窄鼻孔可以改变气流，因此分泌有粘液的鼻腔能够更有效地湿润和温暖吸入的空气。

"It was probably more essential to have this trait in cold and dry climates," it said.

研究报告写道：“这可能对干冷气候中的人们更重要。”

"People with narrower nostrils probably fared better and had more offspring than people with wider nostrils, in colder climates. This lead to a gradual decrease in nose width in populations living far away from the equator."

“在较寒冷的气候中，较窄鼻孔的人可能比较宽鼻孔的人过得更好一些，有更多的后代。这导致远离赤道的人群鼻子逐渐变窄。”

The nose has had a complex evolutionary⁸ history, however, and researchers suspected that additional factors, such as cultural preferences when picking a mate, have also played a role in shaping the nose.

鼻子演化历史较为复杂。研究人员猜测，可能也有其他因素对鼻子的形状发挥作用，比如对鼻子大小的择偶偏好。

Investigations⁹ into nose shape evolution and climate adaptation may have medical as well as anthropological¹⁰ implications.

对鼻子形状演化历史和气候适应性的研究也有医学和人类学意义。

Studies of human adaptation are essential to our understanding of disease and yield insights into why certain conditions, such as sickle¹¹ cell anemia¹², lactose intolerance or skin cancer, are more common in certain populations.

人类进化的相关研究对我们理解疾病，以及深刻了解为什么特定病症（比如镰状细胞性贫血、乳糖不耐症、和皮肤癌）在某些人群中更常见非常重要。

The researchers said that it may be worth investigating whether the shape of the nose and the size of the nasal cavity impact one's risk of contracting a respiratory disease when living in a climate that is different from one's ancestors.

研究人员表示，当人们生活在与祖先不同的气候中时，鼻子的形状和鼻腔的大小是否能影响一个人患上呼吸疾病的风险，这也许值得研究。