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Male flowers of Gurania makoyana, a Central American plant in the cucumber family, harbor larvae (not visible) of two species of fly; a third fly species infests female flowers of the same species of plant. Some plant species in this family can host as many as 13 different fly species.

A Mosquito Goes Global
The Asian tiger mosquito is on a rampage. Entomologists are impressed, public health officials are nervous, and many of the rest of us are swatting furiously. How did Aedes albopictus become such a scourge?

Layers Within Layers Hint at a Wobbly Martian Climate
Scientists scrutinizing layered rocks on Mars this week in Science that the layers formed in sync with changes in the planet's orbit.

Click Chemistry Clicks Along
Researchers seeking new ways to forge molecules are saving steps and effort by adapting high-yield reactions to fill a variety of needs.

The Hot Question: How New Are the New Superconductors?
Do iron-and-arsenic superconductors work the same way as the older, inscrutable copper-and-oxygen compounds? Early evidence points both ways.

The Energetic Cost of Climbing in Primates
Large primates expend less energy walking than climbing, but smaller ones walk and climb with similar efficiencies, possibly facilitating an evolutionary shift into trees.

Turbulence and Magnetic Fields in the Large-Scale Structure of the Universe
Simulations suggest that shock waves in the early universe could have amplified small magnetic fields into the large, complex intergalactic fields we see today.

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