(Left to right): © Leonard Freed/Magnum Photos; BlankeZr/iStockphoto; siraanamwong/iStockphoto

Top stories: Filthy kitchen sponges, Cold War espionage, and Greeks’ near-mythical origins

Your kitchen sponge harbors zillions of microbes. Cleaning it could make things worse

That sponge in your kitchen sink harbors zillions of microbes, including close relatives of the bacteria that cause pneumonia and meningitis, according to a new study. Surprisingly, boiling or microwaving the sponges doesn’t kill off these microbes. Indeed, the researchers have found that sponges that had been regularly sanitized teemed with a higher percentage of bacteria related to pathogens than sponges that had never been cleaned.

The Greeks really do have near-mythical origins, ancient DNA reveals

Ever since the days of Homer, Greeks have long idealized their Mycenaean “ancestors” in epic poems and classic tragedies that glorify the heroes who went in and out of favor with the Greek gods. Although these ancestors were fictitious, scholars have long debated whether today’s Greeks descend from the actual Mycenaeans, who dominated mainland Greece and the Aegean Sea from about 1600 B.C.E. to 1200 B.C.E. Now, ancient DNA suggests they did, and that only a small proportion of their DNA comes from later migrations to Greece.

Could diabetes spread like mad cow disease?

Prions are insidious proteins that spread like infectious agents and trigger fatal conditions such as mad cow disease. A protein implicated in diabetes, a new study suggests, shares some similarities with these villains. Researchers transmitted diabetes from one mouse to another just by injecting the animals with this protein. The results don’t indicate that diabetes is contagious like a cold, but blood transfusions, or even food, may spread the disease.

After French drug trial tragedy, European Union issues new rules to protect study volunteers

The European Medicines Agency has issued new, stricter rules for studies that test drugs in people for the first time. They aim to better protect participants in such first-in-human studies—often healthy volunteers who receive a financial reward. The guideline will take effect in February 2018 and comes in the wake of a tragedy in a French drug study last year that led to the death of one man and serious neurological damage in four others. But some say the revision isn’t going far enough.

Elderly chimps may get Alzheimer’s, renewing interest in studying these animals

Researchers have discovered tell-tale signs of Alzheimer’s disease in 20 elderly chimpanzee brains, rekindling a decades-old debate over whether humans are the only species that develop the debilitating condition. Whether chimps actually succumb to Alzheimer’s or are immune from symptoms despite having the key brain abnormalities is not clear. But either way, the work suggests that chimps could help scientists better understand the disease and how to fight it—if they could get permission to do such studies on these now-endangered animals.

Cold War espionage paid off—until it backfired, East German spy records reveal

From 1957 to 1985, former Nazi party member and physicist Hans Rehder stole thousands of invaluable files from his employers, West German electronics firms Telefunken and AEG, and delivered them to East German agents for a monthly fee. Although spying paid off for Rehder, economists and historians have long wondered whether industrial espionage is worth it for the country doing the spying. Now, researchers have analyzed more than 150,000 previously classified documents from the former East German Ministry for State Security (also known as the Stasi) to reach a surprising conclusion: Stealing can boost economic productivity in the short term, but it cannibalizes long-term investment in research and development.