Hamsters Don't Smile: How to Know if Your Pet is Happy

It's unfortunate for pet owners everywhere, but we all know that hamsters don't smile. Like many other animals, these adorable rodent's aren't wired to think that bearing one's teeth is a sign of pleasure or affection. So how can you know if your little fuzz ball is happy? Scientists think they have the answer.

That's at least according to a study recently published in the journal Royal Society Open Science which details how if you want to know how Mr Cuddles really reels, you're going to need some water bottles. That's because, as it turns out, happy hamsters are optimist and willing to try new things.

To conduct their study, a pair of researchers at Liverpool John Moores University trained 30 Syrian hamsters to expect sugar water in a drinker placed at one location. The scientists then introduced a bitter quinine water, which the hamsters learned to expect in another location. Predictably, the hamsters became fans of the sweet water, but avoided the bitter water all together.

The researchers then gave half of the hamsters a range of enrichment devices including hammocks, extra bedding, ledges, and chews all designed to improve mood. After the hamsters were given time to enjoy their improved (or not) environments, a third ambiguous water drinker was added to each cage - placed somewhere between the bitter and sweet waters. (Scroll to read on...)

Time and time again, the hamsters proved that an enriched life led to a more explorative and optimistic lifestyle, with happy hamsters frequently taste-testing the new water. The unhappy hamsters - those with bare cages - rarely, if ever, drank from anything but the sweet-water drinker.

"Judgment bias studies let us examine the effect of emotions on cognitive processes and are important measures for improving animal welfare," Nicola Koyama, an author of the study, explained in a statement. "Hamsters are often a child's first pet and we've shown that what goes into a cage (ledges, chews, hammocks and material to dig in) has a positive impact on a hamster's emotional state and thus, their well-being."

"The important note for pet owners is that ensuring pets have adequate opportunities to express natural behaviors in captivity improves their mood and is essential for their welfare,' added author Emily Bethell.

That is to say, a happy hamster is a hamster that at least gets to pretend he lives in the natural world. You can interpret that admission how you see fit, but I expect to see #freethehamsters trending on Twitter by tomorrow morning.

Note: Please don't actually release your hamsters. The golden (Syrian) hamster, the most common of household hamsters, is actually a vulnerable species in the wild, largely because it is an agricultural pest frequently trapped and poisoned.

For more great nature science stories and general news, please visit our sister site, Headlines and Global News (HNGN).

- follow Brian on Twitter @BS_ButNoBS