Research has found that two strains of Africa’s most common malaria mosquito are speciating—creating new populations with different characteristics and thus evolving into new species.
Scientists studied the Anopheles gambiae mosquito, which is the primary cause of malaria spreading in sub-Saharan Africa. Dr. Maria Lawniczak, a member of the team from Imperial College London, says that the findings show that mosquitoes are evolving even more quickly than scientists had thought.
The two strains, known as M and S, were scattered throughout the insects’ DNA. The changes took place in areas that are likely to affect development, feeding behaviour and reproductive behaviour.
A subsequent study that compared the two strains revealed that they were evolving differently. This is thought to be in response to different environmental factors, such as larval habitats, predators and infectious agents.
Malaria is a deadly disease that affects millions of people around the world. It is responsible for one-fifth of deaths among African children. The discovery has serious implications for the fight against malaria, as these newly evolved insects could become immune to control strategies.
“Strategies that might work against one strain of mosquito might not be effective against another. It’s important to identify and monitor these hidden genetic changes in mosquitoes if we are to succeed in bringing malaria under control by targeting mosquitoes.”
By linking specific genetic variations with particular mosquito populations, researchers and public health officials are hoping to determine the types of mosquitoes to be found in particular geographic and ecological settings.