第2036期:Researchers Make Surprising Discovery about Ancient Mosquitoes

Hundreds of thousands of people worldwide are killed every year by malaria and other diseases that are spread through mosquito bites. 全世界每年有数十万人死于疟疾和其他通过蚊虫叮咬传播的疾病。Female mosquitoes are responsible for these deadly bites because they have a special mouth design that male mosquitoes do not have. 雌性蚊子对这些致命的叮咬负有责任，因为它们具有雄性蚊子没有的特殊嘴部设计。 But it has not always been that way. Researchers said they have discovered the oldest-known fossils of mosquitoes - two males located in pieces of an ancient orange-colored substance known as amber. 但情况并非总是如此。研究人员表示，他们发现了已知最古老的蚊子化石——两只雄性蚊子位于一种古老的橙色物质琥珀中。 The male mosquitoes date to 130 million years ago. They were found near the modern town of Hammana in Lebanon. To researchers' surprise, the male mosquitoes had long mouthparts seen now only in females. 雄性蚊子的历史可以追溯到1.3亿年前。它们是在黎巴嫩现代城镇哈马纳附近发现的。令研究人员惊讶的是，雄性蚊子有长长的口器，现在只见于雌性蚊子。 Dany Azar is a researcher at the Chinese Academy of Sciences' Nanjing Institute of Geology and Paleontology and Lebanese University. Azar said they were clearly blood-eaters. The lead writer of the study, recently published in Current Biology, added, "This discovery is a major one in the evolutionary history of mosquitoes." 丹尼·阿扎尔（Dany Azar）是中国科学院南京地质古生物研究所和黎巴嫩大学的研究员。阿扎尔说，他们显然是食血者。这项研究最近发表在《当代生物学》上，该研究的主要作者补充道：“这一发现是蚊子进化史上的重大发现。” The two fossilized mosquitoes, both representing the same species that has died off, are similar in size and appearance to modern mosquitoes. However, the mouthparts used for getting blood are shorter than in today's female mosquitoes. 这两种蚊子化石均代表已灭绝的同一物种，其大小和外观与现代蚊子相似。然而，用于吸血的口器比今天的雌性蚊子短。Study co-writer André Nel of the National Museum of Natural History of Paris described the finding as "quite surprising." 巴黎国家自然历史博物馆的研究报告合著者安德烈·内尔称这一发现“非常令人惊讶”。 The special anatomy of the two mosquitoes was beautifully saved in the fossils. Both insects had sharp and triangle-shaped jaw anatomy and a long structure with tooth-like elements. 两只蚊子的特殊解剖结构被完美地保存在化石中。这两种昆虫都有锋利的三角形下颌解剖结构和带有齿状元素的长结构。 The researchers said they suspect that mosquitoes evolved from insects that did not consume blood. They think that the mouthparts that were developed for getting blood meals were originally used to pierce plants to get nutritious fluids. 研究人员表示，他们怀疑蚊子是从不吸食血液的昆虫进化而来的。他们认为，为获取血液而开发的口器最初是用来刺穿植物以获得营养液的。Plant evolution may have affected the differences in feeding between male and female mosquitoes. At the time when these two mosquitoes became stuck in tree sap that eventually became amber, flowering plants were beginning to spread for the first time.植物进化可能影响了雄性和雌性蚊子之间的摄食差异。当这两只蚊子被困在树液中并最终变成琥珀时，开花植物第一次开始蔓延。 From the findings, Azar said that all early mosquitoes, both male and female, were bloodsucking. And male mosquitoes lost the ability later. 阿扎尔表示，根据研究结果，所有早期蚊子，无论雄性还是雌性，都是吸血的。而雄性蚊子后来就失去了这种能力。 The researchers said while these are the oldest mosquito fossils, mosquitoes probably appeared millions of years earlier. They noted that molecular evidence suggests mosquitoes developed from about 200 million to 145 million years ago. 研究人员表示，虽然这些是最古老的蚊子化石，但蚊子可能出现在数百万年前。他们指出，分子证据表明蚊子是在大约 2 亿至 1.45 亿年前形成的。 There are more than 3,500 species of mosquitoes worldwide, found everywhere except Antarctica. Some species spread diseases such as malaria, yellow fever, Zika fever, dengue and others. The World Health Organization says more than 400,000 people die annually from malaria - a parasitic infection - mostly children under age 5. 全世界有超过 3,500 种蚊子，除南极洲外，到处都有蚊子的踪迹。有些物种传播疟疾、黄热病、寨卡热、登革热等疾病。世界卫生组织表示，每年有超过 40 万人死于疟疾（一种寄生虫感染），其中大多数是 5 岁以下的儿童。