Researchers Make Surprising Discovery about Ancient Mosquitoes
2023-12-11
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1Hundreds of thousands of people worldwide are killed every year by malaria and other diseases that are spread through mosquito bites.
2Female mosquitoes are responsible for these deadly bites because they have a special mouth design that male mosquitoes do not have.
3But it has not always been that way.
4Researchers said they have discovered the oldest-known fossils of mosquitoes - two males located in pieces of an ancient orange-colored substance known as amber.
5The male mosquitoes date to 130 million years ago.
6They were found near the modern town of Hammana in Lebanon.
7To researchers' surprise, the male mosquitoes had long mouthparts seen now only in females.
8Dany Azar is a researcher at the Chinese Academy of Sciences' Nanjing Institute of Geology and Paleontology and Lebanese University.
9Azar said they were clearly blood-eaters.
10The lead writer of the study, recently published in Current Biology, added, "This discovery is a major one in the evolutionary history of mosquitoes."
11The two fossilized mosquitoes, both representing the same species that has died off, are similar in size and appearance to modern mosquitoes.
12However, the mouthparts used for getting blood are shorter than in today's female mosquitoes.
13Study co-writer André Nel of the National Museum of Natural History of Paris described the finding as "quite surprising."
14The special anatomy of the two mosquitoes was beautifully saved in the fossils.
15Both insects had sharp and triangle-shaped jaw anatomy and a long structure with tooth-like elements.
16The researchers said they suspect that mosquitoes evolved from insects that did not consume blood.
17They think that the mouthparts that were developed for getting blood meals were originally used to pierce plants to get nutritious fluids.
18Plant evolution may have affected the differences in feeding between male and female mosquitoes.
19At 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.
20From the findings, Azar said that all early mosquitoes, both male and female, were bloodsucking.
21And male mosquitoes lost the ability later.
22The researchers said while these are the oldest mosquito fossils, mosquitoes probably appeared millions of years earlier.
23They noted that molecular evidence suggests mosquitoes developed from about 200 million to 145 million years ago.
24There are more than 3,500 species of mosquitoes worldwide, found everywhere except Antarctica.
25Some species spread diseases such as malaria, yellow fever, Zika fever, dengue and others.
26The World Health Organization says more than 400,000 people die annually from malaria - a parasitic infection - mostly children under age 5.
27I'm John Russell.
1Hundreds of thousands of people worldwide are killed every year by malaria and other diseases that are spread through mosquito bites. 2Female mosquitoes are responsible for these deadly bites because they have a special mouth design that male mosquitoes do not have. 3But 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. 4The 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. 5Dany 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." 6The 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. 7Study co-writer André Nel of the National Museum of Natural History of Paris described the finding as "quite surprising." 8The 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. 9The 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. 10Plant 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. 11From the findings, Azar said that all early mosquitoes, both male and female, were bloodsucking. And male mosquitoes lost the ability later. 12The 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. 13There 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. 14I'm John Russell. 15Will Dunham reported on this story for Reuters. John Russell adapted it for VOA Learning English. 16_________________________________________________ 17Words in This Story 18fossil - n. something (such as a leaf, skeleton, or footprint) that is from a plant or animal which lived in ancient times 19evolution - n. an idea that the differences between plants and animals are because of changes that happened by a natural process over a very long time 20species - n. a group of animals or plants that are similar and can produce young animals or plants 21anatomy -- n. the parts that form a living thing 22pierce -- v. to make a hole in or through something 23sap - n. a watery juice inside a plant that carries the plant's food