Consider, if you will, a repulsive case of food poisoning. You may try to hold it in, but at some point you’re gonna spew. But not every species is that lucky—and one day their inability to barf could help humans better tolerate life-saving treatments that make us nauseated, like chemotherapy.
The unfortunate creatures in question are all rodents. That’s right: Rats can’t hurl. Don’t envy them their good fortune. Your gift of gag means you can expel gross or harmful things from your heaving guts. Rats can’t up-chuck things that could do them in, like poison.
That’s obviously bad news for rodents. But for Linda Parker, a behavioral neuroscientist at the University of Guelph, it’s a blessing. Parker’s trying to get to the bottom of vomiting and nausea in human beings, and not-barfing rats are the key to her research. With the help of a horde of nauseous rodents, Parker and her colleagues have discovered several truths that could one day improve the lives of chemotherapy patients, as well as other humans who suffer from debilitating queasiness.
Parker spends a lot of time working on gaping—the behavior rats exhibit when they feel sick to their stomachs. Much like humans, rats retch when they experience disgust, opening their mouth and jaw wide, and when they taste a flavor they associate with illness—indeed, any unfamiliar flavor at all—they exhibit such behavior for about 40 minutes.