Scientists battling the deadliest creature on Earth have been alarmed to discover that it is rapidly evolving into two distinct species. The Anopheles gambiae mosquito, responsible for some million deaths from malaria every year, has split into two genetically different strains, the Independent reports. Scientists warn that this will complicate eradication efforts because strategies that work against one strain may not work against the other.
The two strains of Anopheles gambiae—by far the most efficient malaria carrier among the many species of mosquitos—appear identical but have very different DNA. One strain appears to be much more efficient at laying eggs in rice paddies. "You really cannot tell by looking at them that they are so different genetically," a researcher says. "Yet we have to know that any efforts directed at controlling mosquitoes will work in all the different groups that transmit malaria." (More malaria stories.)