Primatologist Frans de Waal has spent his lifetime studying the lives of animals, especially our closest cousins, the chimpanzees. de Waal has observed their shifting alliances and the structure of their political ranks. He has seen bitter conflicts break out, only to be mended by peaceful, respected mediators. And he has witnessed chimpanzees grieve for, and attempt to comfort, their dead and dying. But one of the most touching reflections in his new book, Mama’s Last Hug: Animal Emotions and What They Tell Us About Ourselves, is the story he tells of a female chimp who didn’t produce enough milk to feed her young. When de Waal taught her to feed her baby with a bottle instead, she repaid him with what most of us would recognize as gratitude: holding both of de Waal’s hands and whimpering sadly if he tried to leave. The book explores many stories of animal emotions from across the animal kingdom, and it might leave you wondering how unique humans really are.

Gentrification happens when a previously low-income or working class neighborhood sees an influx of well-off new residents. Rents go up, new development sets in, and the neighborhood’s original residents may be displaced by those with more money. Cities who can recognize gentrification in progress can take steps to prevent displacement and funnel resources, or even slow the neighborhood’s changes directly. But while a new yoga studio or fancy coffee shop may be one obvious sign of rising rents, there are earlier indications that might help cities fend off some of the side effects sooner—building improvements like new siding, landscaping, and more go markedly up as new money arrives. Writing in the journal PLOS One this week, a research team at the University of Ottawa describes one new tool in the toolkit: they turned to Google’s Street View, and taught an AI system to recognize when an individual house had been upgraded. Putting those upgrades on a map revealed not just areas the researchers already knew were gentrifying, but also other pockets where the process had begun unnoticed. Michael Sawada, a professor of geography, environment, and geomatics at the University of Ottawa, explains the big data approach to catching gentrification in action.

Anyone who has glanced at the back of a bottle of aspirin or a box of allergy tablets has seen it: the “Inactive Ingredients” list. All medications include compounds that help stabilize the drug or aid in its absorption. They aren’t given a second thought because they’re “inactive,” which suggests that these ingredients don’t do any harm. But in fact, according to a new study out this week, over 90 percent of medications have inactive ingredients that can cause allergic reactions in certain patients, including peanut oil, lactose, and gluten.

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