India leaps into his pool, pouncing on a purple plastic egg—his favorite toy, according to his caregivers. After a few minutes, the tiger ambles over to his watering tub. Instead of taking a drink, he plops in and closes his eyes in contentment. Although he’s young—roughly 10 months old on this June...

Flying back and forth over Cape Cod Bay, a survey plane spotted a half dozen of the world’s rarest creatures: North Atlantic right whales. Such sightings are good news. The species hovers near extinction—by one estimate, fewer than 360 remain. Each time researchers locate a whale, they take pictures...