Tuesday, January 27, 2009
Sexy mosquitoes? Superfly!
The other week I was browsing news sites after reading the chapter in The Coming Plague about cities and their effects on disease ecology. One of the most interesting parts of this chapter was the discussion of Dengue Fever, and how the spread of this disease and the mosquitoes that carry it was always facilitated by human attempts to curb the spread of this disease. Mosquito control has been a big part of the spread (or hopefully lack thereof) of many tropical diseases. Dr. Latto even mentioned the funny thing about DDT killing Bolivian cats last week, and how that may have contributed to an outbreak of a very nasty virus. We have come a long way from DDT now, and vector control methods are getting pretty sophisticated.
Scientists have been searching for ways to reduce the population of tiger mosquitoes in the world, as they are the primary carriers of malaria. What better way to do this than to simply stop them from creating offspring? Now it looks like that is a possibility. If sterile male mosquitoes were released into the wild, theoretically the population of mosquitoes would decline. Some scientists have even discovered ways to genetically engineer mosquitoes that can't carry malaria or dengue. The problem with this theory has been that female mosquitoes can tell that these guys have been altered, and they don't find the new males attractive at all.
In this BBC article scientists explain that they have discovered what mosquitoes find attractive in a mate, and apparently it is perfect pitch! When mosquitoes mate they beat their wings to create a humming harmony, and females can judge the fitness of male mosquitoes according to how well they "sing" with their wings. Previously, female mosquitoes rejected the genetically altered males. Maybe by releasing sexy sterile male mosquitoes into the wild we could see some very interesting effects on the ecology of the tropical illnesses that they traditionally carry.