The Norman Transcript

Nation/World

May 26, 2013

Roaches quickly lose sweet tooth to survive

NEW YORK — For decades, people have been getting rid of cockroaches by setting out bait mixed with poison. But in the late 1980s, in an apartment test kitchen in Florida, something went very wrong.

A killer product stopped working. Cockroach populations there kept rising. Mystified researchers tested and discarded theory after theory until they finally hit on the explanation: In a remarkably rapid display of evolution at work, many of the cockroaches had lost their sweet tooth, rejecting the corn syrup meant to attract them.

In as little as five years, the sugar-rejecting trait had become so widespread that the bait had been rendered useless.

“Cockroaches are highly adaptive, and they’re doing pretty well in the arms race with us,” said North Carolina State University entomologist Jules Silverman, discoverer of the glucose aversion in that Florida kitchen during a bait test.

The findings illustrate the evolutionary prowess that has helped make cockroaches so hard to stamp out that it is jokingly suggested they could survive nuclear war.

In a study published Thursday in the journal Science, Silverman and other researchers explain the workings of the genetic mutation that gave some roaches a competitive advantage that enabled them to survive and multiply.

The key is certain neurons that signal the brain about foods.

In normal cockroaches, glucose excites neurons that tell the brain “Sweet!” In the mutant insects, glucose activates neurons that say “Sweet!” and ones that say “Yuck!” The “Yuck!” neurons dampen the signal from the others, so the brain gets the message the taste is awful. This unusual nerve activity appeared in glucose-hating cockroaches collected from Puerto Rico as well as descendants of the Florida insects.

The research focused on the German cockroach, a small kind that can hitch a ride into your home in a grocery bag, not that big lunk known as the American cockroach. Such finicky eating habits have also been seen in these smaller roaches in Southern California, Cincinnati, Indiana, South Korea and Russia. Scientists are now looking to see if other kinds of cockroaches show aversion to glucose.

1
Text Only | Photo Reprints
Nation/World
  • FedEx charges raising online pharmacy issues

    SAN FRANCISCO — FedEx Corp., the latest company accused in a federal probe involving illegal online pharmacies, says it will fight the charges that it knowingly shipped drugs to people who lack valid prescriptions....

    July 27, 2014

  • EU, U.S. seek to curb Putin’s Ukraine course

    BRUSSELS — Months after Russia annexed Crimea and stepped up support for separatists in eastern Ukraine, Europe and the United States are still searching for a way to persuade Russian President Vladimir Putin to change course....

    July 27, 2014

  • Fighting intense near crash

    DONETSK, Ukraine — Ukrainian armed forces mounted a major onslaught against pro-Russian separatist fighters Sunday in an attempt to gain control over the area where a Malaysia Airlines plane was downed earlier this month....

    July 27, 2014

  • Gaza war rages despite truce pledges

    GAZA CITY, Gaza Strip — Israel and Hamas launched new attacks Sunday in the raging Gaza war, despite going back and forth over proposals for a temporary halt to nearly three weeks of fighting ahead of a major Muslim holiday....

    July 27, 2014

  • Hamas fires rockets on Israel, ending 12-hour lull

    BEIT HANOUN, Gaza Strip — Hamas said it fired five rockets at Israel late Saturday after rejecting Israel’s offer to extend a 12-hour humanitarian cease-fire by four hours, casting new doubt on international efforts to broker an end to 19 ...

    July 27, 2014

  • Death shows Ebola can spread through air travel

    ABUJA, Nigeria — Nigerian health authorities raced to stop the spread of Ebola on Saturday after a man sick with one of the world’s deadliest diseases brought it by plane to Lagos, Africa’s largest city with 21 million people. The fact ...

    July 27, 2014

  • Police ID kids killed in Philly carjacking crash

    PHILADELPHIA — Two carjackers who fled after ramming a stolen SUV into a family selling fruit for their church, killing three young siblings, were still on the run Saturday as the reward for their capture topped $100,000. The children’s ...

    July 27, 2014

  • U.S.: Russia firing across border

    KIEV, Ukraine — Russia is launching artillery attacks from its soil on Ukrainian troops and preparing to move heavier weaponry across the border, the U.S. and Ukraine charged Friday in what appeared to be an ominous escalation of the ...

    July 26, 2014

  • Small holes cause big jitters

    SEOUL, South Korea — For the developers of the world’s sixth tallest building near Seoul, a mysteriously shrinking lake and the appearance of small sinkholes in residential neighborhoods couldn’t have come at a more inopportune time. ...

    July 26, 2014

  • Secret photo victims must describe trauma for case

    BALTIMORE — Thousands of women whose genitals might have been photographed during gynecological exams can share a $190 million settlement from Johns Hopkins Health System. But they’ll have to describe their trauma before seeing any money. ...

    July 26, 2014