The mother goat's floppy ears perk up. From across the field, she hears one of her kids—not the new baby that's still nursing, but the grown-up kid who's packed up and moved to a different pen. Even though she no longer sees or feeds her older offspring, she'd know that bleat anywhere.
It's hard to know how well animals recognize and remember each other's voices; you have to follow groups of animals around for long stretches and keep track of how recently they've seen each other. Yet we have a few answers already. An Australian sea lion remembers its mother's voice for years after it's left her side. Cotton-top tamarins recognize relatives' calls even when they haven't seen them for several years. African elephants have been shown to remember a former group member's voice 12 years later.
Domestic goats are good subjects for this area of research: they're chatty, they're ...
