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Oldest mosquito fossil comes with a bloodsucking surprise

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Oldest mosquito fossil comes with a bloodsucking surprise


An undated handout picture of a view from above of the physique of a fossilized male mosquito trapped in amber present in central Lebanon courting to about 130 million years in the past.
| Photo Credit: Reuters

Hundreds of 1000’s of individuals worldwide are killed yearly by malaria and different ailments unfold by way of the chew of mosquitoes, bugs that date again to the age of dinosaurs. All of those bites are inflicted by females, which possess specialised mouth anatomy that their male counterparts lack.

But it has not at all times been that approach. Researchers mentioned they’ve found the oldest-known fossils of mosquitoes – two males entombed in items of amber courting to 130 million years in the past in the course of the Cretaceous Period and located close to the city of Hammana in Lebanon. To their surprise, the male mosquitoes possessed elongated piercing-sucking mouthparts seen now solely in females.

“Clearly they were hematophagous,” which means blood-eaters, mentioned palaeontologist Dany Azar of the Chinese Academy of Sciences’ Nanjing Institute of Geology and Paleontology and Lebanese University, lead creator of the research revealed this week within the journal Current Biology. “So this discovery is a major one in the evolutionary history of mosquitoes.”

The two fossilized mosquitoes, each representing the identical extinct species, are related in dimension and look to trendy mosquitoes, although the mouthparts used for acquiring blood are shorter than in right now’s feminine mosquitoes.

“Mosquitoes are the most notorious blood-feeders on humans and most terrestrial vertebrates, and they transmit a certain number of parasites and diseases to their hosts,” Azar mentioned.

“Only fertilized female mosquitoes will suck blood, because they need proteins to make their eggs develop. Males and unfertilized females will eat some nectar from plants. And some males do not feed at all,” Azar added.

Some flying bugs – tsetse flies, as an illustration – have hematophagous males. But not trendy mosquitoes.

“Finding this behavior in the Cretaceous is quite surprising,” mentioned paleontologist and research co-author André Nel of the National Museum of Natural History of Paris.

The delicate anatomy of the 2 mosquitoes was superbly preserved within the fossils. Both displayed exceptionally sharp and triangle-shaped jaw anatomy and an elongated construction with tooth-like projections.

The researchers mentioned they think that mosquitoes advanced from bugs that didn’t devour blood. They hypothesize that the mouthparts that grew to become tailored for acquiring blood meals initially have been used to pierce crops to get entry to nutritious fluids.

Plant evolution could have performed a position within the feeding divergence between female and male mosquitoes. At the time when these two mosquitoes grew to become caught in tree sap that finally grew to become amber, flowering crops have been starting to flourish for the primary time on the Cretaceous panorama.

“In all hematophagous insects, we believe that hematophagy was a shift from plant liquid sucking to bloodsucking,” Azar mentioned.

The indisputable fact that these earliest-known mosquitoes are bloodsucking males, Azar added, “means that originally the first mosquitoes were all hematophagous – no matter whether they were males or females – and hematophagy was later lost in males, maybe due to the appearance of flowering plants, which are contemporaneous with the formation of Lebanese amber.”

Plenty of animals have been current to offer blood meals: dinosaurs, flying reptiles referred to as pterosaurs, different reptiles, birds and mammals.

The researchers mentioned whereas these are the oldest fossils, mosquitoes most likely originated thousands and thousands of years earlier. They famous that molecular proof suggests mosquitoes arose in the course of the Jurassic Period, which ran from about 200 million to 145 million years in the past.

There are greater than 3,500 species of mosquitoes worldwide, discovered all over the place besides Antarctica. Some grow to be illness vectors transmitting malaria, yellow fever, Zika fever, dengue and different ailments. According to the World Health Organization, greater than 400,000 folks die yearly from malaria – a parasitic an infection – largely kids beneath age 5.

“On the other side, mosquitoes help to purify the water in ponds, lakes and rivers,” Nel mentioned. “In general, an animal can be a problem but also can be helpful.”

  • Hundreds of 1000’s of individuals worldwide are killed yearly by malaria and different ailments unfold by way of the chew of mosquitoes, bugs that date again to the age of dinosaurs.
  • Researchers mentioned they’ve found the oldest-known fossils of mosquitoes – two males entombed in items of amber courting to 130 million years in the past in the course of the Cretaceous Period and located close to the city of Hammana in Lebanon.
  • There are greater than 3,500 species of mosquitoes worldwide, discovered all over the place besides Antarctica. Some grow to be illness vectors transmitting malaria, yellow fever, Zika fever, dengue and different ailments.



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