Scientists have discovered a 100-million-year-old mosquito perfectly preserved in amber. They plan to use blood trapped inside the mosquito to clone dinosaurs and resurrect them from the dead. Just kidding. The ancient mosquito actually sheds light on the origins of malaria, a disease that kills over 400,000 people each year.
The team of researchers from Oregon State University realized their little specimen belonged to a new genus and species, which they named Priscoculex burmanicus. It was found in amber in Myanmar that dates back to the mid-Cretaceous era. While the species is brand new, it shares many similarities with certain mosquitoes still buzzing about today, namely the anopheline mosquitoes, which are famous for carrying and transmitting malaria.
P. burmanicus and today’s anopheline mozzies have various things in common when it comes to their wing veins, antennae, abdomen, and proboscis (their long, blood-sucking mouthpart). This suggests that the new discovery is an early lineage of today’s disease vectors, which could mean they were carrying malaria 100 million years ago. The findings are published in the journal Historical Biology.
“Mosquitoes could have been vectoring malaria at that time, but it’s still an open question,” said George Poinar Jr. of Oregon State University’s College of Science. “Back then anopheline mosquitoes were probably biting birds, small mammals, and reptiles since they still feed on those groups today.”
Malaria is caused by a number of parasites belonging to the Plasmodium genus. When infected female mosquitoes bite humans and animals to feed on their blood, the parasite is transmitted. The World Health Organization (WHO) estimates that nearly half of the world’s human population is at risk of malaria, with those living in sub-Saharan Africa most at risk. Malaria infections are treatable, but an effective vaccine remains elusive, so preventative measures include insecticide and mosquito nets.
But could mosquito-borne malaria have also wreaked havoc on the dinosaurs that lived 100 million years ago? Potentially, according to Poinar.
“There were catastrophic events that happened around that time, such as asteroid impacts, climatic changes, and lava flows,” he wrote in his 2007 book What Bugged the Dinosaurs? Insects, Disease and Death in the Cretaceous. “It’s still clear that dinosaurs declined and slowly became extinct over thousands of years, which suggests other issues must also have been at work. Insects, microbial pathogens such as malaria, and other vertebrate diseases were just emerging around that time.”
The new study also sheds light on how Anopheles mosquitoes might have become so widespread – today they’re found across the globe. The researchers note that their ancestors could have spread through Gondwana, an ancient supercontinent, before it divided into what is now Africa, South America, Madagascar, India, Australia, Antarctica, and Arabia.
“This discovery provides evidence that anophelines were radiating – diversifying from ancestral species – on the ancient megacontinent of Gondwana because it is now thought that Myanmar amber fossils originated on Gondwana,” Poinar explained.
Poinar previously discovered malaria in a fossilized mosquito found in the Dominican Republic, which was 15 to 20 million years old. It marked the first time Plasmodium had been found in fossil form.
"I think the fossil evidence shows that modern malaria vectored by mosquitoes is at least 20 million years old, and earlier forms of the disease, carried by biting midges, are at least 100 million years old and probably much older," he said at the time.
Learning more about the evolution of malaria and its relationship with mosquitoes could aid scientists coming up with new tricks to tackle the devastating disease.
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