(Left to right): AKG-IMAGES/NEWSCOM; ESO/M. Kornmesser; Sukho Song

Top stories: Immigrant bloodlines analyzed, illegal petunias destroyed, and superstar surgeon fired again

There's no such thing as a 'pure' European—or anyone else

New studies show that there is no such thing as "pure" European—or anyone else. Almost all of us are the children of repeated ancient migrations, according to researchers who study human origins. Using revolutionary new methods to analyze DNA and the isotopes found in bones and teeth, scientists are exposing the tangled roots of peoples around the world. Few of us are actually the direct descendants of the ancient skeletons found in our backyards or historic homelands. And only a handful of groups today, such as Australian Aborigines, have deep bloodlines untainted by mixing with immigrants.

Superstar surgeon fired, again, this time in Russia

After Paolo Macchiarini’s star fell in Sweden, the Italian surgeon still had a place to shine: Russia. The Karolinska Institute in Stockholm fired him in March 2016 for multiple ethical violations, including a breach of “fundamental values" and "scientific negligence." But Russia had long showered Macchiarini with funding and opportunities to perform his experimental surgeries to implant artificial tracheas, and it allowed him to stay. Now, a year later, his Russian refuge has ended as well.

Closest alien world to our solar system could be ripe for life, models suggest

Could alien life reside close to our stellar neighborhood? Astronomers are taking that question a bit more seriously as new models increasingly suggest that the closest Earth-like planet to our solar system could be habitable. One research team predicted that it would be possible for the exoplanet Proxima b—orbiting our nearest neighbor star—to harbor liquid water on its surface. Now, another team has taken a climate model designed for Earth and pasted it onto Proxima b and found an even wider range of circumstances in which Proxima b could have liquid water than the earlier study.

U.S. flower sellers rush to destroy illegal GE petunias

The U.S. Department of Agriculture announced this week that U.S. flower distributors have begun to destroy countless petunia plants after federal scientists confirmed that they were genetically engineered (GE) to produce vivid orange, red, and purple blooms. The agency says the flowers pose no risk to the environment or to human health, but GE organisms need special permits to be sold in the United States. Testing continues, but the agency says it has already confirmed nine unwelcome varieties, including ones called African Sunset, Trilogy Mango, and Sweetunia Orange Flash.

Gecko-inspired gripper could help robots climb walls

If you want a robot to pick up a coffee cup, a cherry tomato, or a bag of packaged food, you’ll have to deal with a lot of programming and quite possibly some cleanup in aisle 3. A child can handle all kinds of shapes and materials, and apply the right combination of force and delicacy when lifting them, but getting machines to reproduce these seemingly simple skills hasn’t been easy. Now, a team of researchers has developed a new way to pick up objects that solves many of these problems. Modeled on geckos’ toes, it could also help robots climb irregularly shaped walls.