研究:降水变化可能影响生物的自然选择

  新华社旧金山3月5日电(记者马丹)一个国际钻研团队日前在新一期美国《科学》杂志上申报说,降水变更可能在动植物的自然选择历程中起到关键感化。   自然选择是解释生物为适应情况而进…

  新华社旧金山3月5日电(记者马丹)一个国际钻研团队日前在新一期美国《科学》杂志上申报说,降水变更可能在动植物的自然选择历程中起到关键感化。

  自然选择是解释生物为适应情况而进化、生计的机制。气候变更的后果之一是举世降水模式呈现非常,一些地方降水次数削减但降水量暴增,一些地方干旱成为常态。申报作者之一、美国加利福尼亚大年夜学伯克利分校副教授斯蒂芬妮·卡尔森说,他们的钻研证实,自然选择的变更平日与合营的气候前提相关联,尤其是降水身分。

  虽然此前有大年夜量钻研显示气候变更影响生态和物种进化,但科学家对气候变更若何影响自然选择这一关键的进化机制还不清楚。卡尔森指出,最新钻研结果显示,气候变更有可能改变举世范围内生物的适应性。

  钻研职员网络了168份已颁发的钻研申报,这些申报对天下各地不合动植物种群的自然选择加以量化。钻研职员对这些申报进行阐发,把自然选择模式与气候数据对应起来,发明20%至40%的自然选择变更可能归因于当地降水变更

 

  钻研职员表示,这一发明很紧张,尤其是斟酌到这项钻研涉及举世范围。这阐明依据像降水这种常见的气候身分,自然选择的变更在必然程度上是可以猜测的。

  钻研职员以一种生活在厄瓜多尔加拉帕戈斯群岛上的雀科小鸟为例,阐明降水变更也会导致动植物随之发生变更。钻研职员解释说,这种鸟的鸟喙在外形和大年夜小上已历经几代改变,缘故原由是多年来降水变更影响了这种鸟类赖以为生的种子的大年夜小。

  钻研职员强调,他们的钻研还注解,与降水比拟,气温变更对生物自然选择的影响要小得多,但也有可能是这组数据中气温的影响没有表现出来。

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