AUSTIN, TEXAS — Success of an indoor spraying campaign to combat malaria on an African island may have started a worrisome trend in local mosquito evolution.

Since 2004, using pesticides inside homes has eradicated two of four malaria-spreading Anopheles mosquitoes on Bioko Island in Equatorial Guinea, vector biologist Jacob I. Meyers of Texas A&M University in College Station reported June 19 at the Evolution 2016 meeting. Numbers of the remaining two species have dropped. Yet the dregs of these supposedly homebody species are showing a rising tendency to fly outdoors looking for a blood meal, Meyers and colleagues cautioned. The results were also reported April 26 in Malaria Journal.

If the mosquitoes continue to shift toward outside bloodsucking, the campaign could lose some of its bite. Repeated treatments of indoor walls with pesticides that kill mosquitoes clinging to them may not be so effective if the pests venture from home.

What’s changing about these mosquitoes remains to be seen, but this looks like more than simple opportunism, Meyers said. Bed nets are not common, so Meyers doubts that the mosquitoes fly outdoors because no one is available to bite indoors. Nor does their reaction look like escape from repellent pesticides: Outdoor biting didn’t consistently rise after a spraying. The next step is to check for a genetic basis for the shift. Lots of research has explored physiology that lets insects resist pesticides, Meyers said, but the onset of possible resistant behavior has barely been explored.

Bottoms up, from the distant past. Thanks to a new method of analyzing the chemicals in liquids absorbed by clay containers, researchers have uncorked the oldest solid evidence of grape-based wine making in Europe, and possibly the world, at a site in northern Greece.

Chemical markers of red wine were embedded in two pieces of a smashed jar and in an intact jug discovered in 2010 in the ruins of a house destroyed by fire around 6,300 years ago at the ancient farming village of Dikili Tash.
After successfully testing the new technique on replicas of clay vessels filled with wine, then emptied, the scientists identified chemical markers of grape juice and fermentation in clay powder scraped off the inner surfaces of the Dikili Tash finds. None of the vessels contained visible stains or residue, researchers report online May 24 in the Journal of Archaeological Science.

Remains of crushed grapes found near the ancient jar shards and jug had already indicated that Dikili Tash farmers made wine or grape juice, say chemist Nicolas Garnier of École Normale Supérieure in Paris and archaeobotanist Soultana Maria Valamoti of Aristotle University of Thessaloniki in Greece.

Previous reports of ancient wine have largely relied on chemical markers of grapes but not the fermentation necessary to turn them into wine, leaving open the possibility that containers held grape juice. The “juice versus wine” conundrum applies to roughly 7,400-year-old jars from Iran (SN: 12/11/04, p. 371), Garnier says.