2023-12-07 20:00:23
A male mosquito fossil, found in amber in Lebanon, dating back to the early Cretaceous period. DANY AZAR
Behind this beautiful photo of a mosquito caught in amber, questions arise about the origin of this habit that these creatures have developed to bite men, women and children. Two specimens of the family Culicidae, thus found in Lebanon in a remarkable condition, date back to the beginning of the Cretaceous period, almost 145 million years ago. In a study published Monday December 4 in Current Biologya team of Lebanese and Chinese researchers explains that the two male mosquitoes studied have “percussive mouthparts, armed with denticulated and sharp mandibles”.
First signatory of this study, Dany Azar, from the Nanjing Institute of Geology and Paleontology of the Chinese Academy of Sciences and the Lebanese University, this equipment shows that “these male fossils were probably bloodsucking”. In other words, they fed on blood sucked from other animals whose skin they pierced using these very particular mouthparts. An intriguing discovery since, today, among mosquitoes, only females are bloodsucking.
Blood-sucking males
We don’t really know how long mosquitoes have been biting. In insects, hematophagy probably emerged due to changing feeding patterns. The transition from aspiration of plant fluids, such as flower nectar, to that of animal fluids. For example, the article’s authors note, “exclusively blood-sucking fleas appear to have diverged from Mecopterida,” an order of insects that today feed on nectar.
The fossils examined in this study are contemporary with the appearance of flowering plants and their differentiation, which caused “coevolution between pollinators and flowering plants”, explains Dany Azar. But the existence of these blood-sucking males complicates the understanding of the transition from a nectar-eating species to a partially blood-eating species. Partially, because mosquitoes of both sexes feed well on flower nectar, animal or human blood being for the female a dietary supplement contributing to the development of her eggs.
The family of Culicidae includes more than 3,000 species of mosquitoes. And in the phylogenetic tree of the mosquito, a gap exists which does not allow the stem group to be clearly identified. Further fossil discoveries will be needed to complete the puzzle.
#Male #mosquitoes #bitten #million #years