If you’ve ever been bitten by a mosquito, it was a female insect that chomped on your skin. Female mosquitoes are hematophagous, which means that they feast on animal blood. They then use the blood to produce their eggs. Male mosquitoes living today are not hematophagous. Instead, they survive on plant nectar because their piercing mouthparts–the proboscis–aren’t strong enough to pierce skin.
[Related: When insects got wings, evolution really took off.]
However, male mosquitoes may have been blood suckers hundreds of millions of years ago. A team of paleontologists found two male mosquito fossils from the Lower Cretaceous period with intact piercing proboscis and sharp mandibles needed to suck blood. The specimens are described in a study published December 4 in the journal Current Biology and help to narrow a “ghost-lineage gap” for mosquitoes.
Hematophagy is the ability for insects to suck on the blood of other animals. It’s believed to have evolved from a shift to using piercing-sucking mouthparts to extract fluids from plants instead of animals. Fleas that currently suck animal blood possibly arose from earlier species of the insects that primarily fed on plant nectar. The evolution of hematophagy has been more difficult to trace, partially due to gaps in the insect fossil record.
The fossils examined for this study were found preserved in amber in Lebanon and date back about 130 to 125 million years. Amber is a fossilized tree resin and deposits in Lebanon are some of the oldest known amber samples that contain traces of living things including insects. Studying this material can close “ghost-lineage gaps,” or a chain of ancestors that does not usually appear in the fossil record. Coelacanths are a famous example of a ghost-lineage gap. These lobe-finned have a long fossil record from the Devonian to the Cretaceous–or a period of about 300 million years. However, they were not found in sediments younger than the…
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