What exactly is a hamster? The basics about us little runners

Hi, it’s Koko! 🐹 Before I hop back onto the wheel, let’s sit down by the seed stash for a moment - I’ll tell you what a hamster actually is. Because while most of you picture us in a bedroom cage, we hamsters have a pretty wild backstory.

There is no single “hamster” (and watch out for hybrids!)

The word “hamster” hides many species. In homes you’ll most often meet:

• The Syrian hamster (also called the golden hamster), Mesocricetus auratus in Latin - the largest of the pet hamsters, and a strict loner.
• Dwarf hamsters of the genus Phodopus - these include the Djungarian, Campbell’s and Roborovski hamsters. They’re little ones, measuring roughly 7-10 cm.

And me? I, Koko, am a Djungarian dwarf hamster (Phodopus sungorus). In the wild my species lives on the dry steppes of Siberia and Kazakhstan.

But let me share a secret: a genetically pure Djungarian is actually rare in pet shops. Almost all “Djungarian” and Campbell’s hamsters on sale are hybrids - crosses of those two species. We have the same number of chromosomes, so we interbreed easily. Unfortunately that carries a genetic burden: especially in trendy colour morphs (like “Mandarin”), there’s often a tendency toward obesity, kidney disease and diabetes. That’s why our home diet has to be strictly free of simple sugars and sweet fruit.

“Winter white” and my winter secret

My species is also known as the winter white dwarf hamster - and for good reason. When the days shorten in winter, our grey-brown summer coat can moult almost to white, which works as camouflage against the snowy steppe. It’s a response to day length (light dropping below about 13 hours), not to temperature itself. The thick, dark-grey fur you see in my photos is my summer colour.

I used to say we don’t hibernate. That’s only half true - we don’t go into deep hibernation the way Syrians can, but we have another brilliant trick: daily torpor. When the day grows short, we can deliberately lower our body temperature from 37°C to below 32°C (sometimes even to 14-19°C) for a few hours. Our metabolism slows right down, which saves energy through the harshest cold.

Syrian hamsters work differently - they’re so-called facultative hibernators. If the temperature at home drops below about 15°C, a Syrian can suddenly slip into deep torpor. It then looks dead: limp and cold to the touch. Don’t panic - you have to warm it up slowly and gradually to room temperature (20-24°C).

A night owl? At home yes, but in the wild a surprise

In cages we come alive when you go to sleep - in captivity we’re active mainly after dusk and at night, because that’s how artificial lighting sets us. But here’s the twist: studies of wild Syrian hamsters surprised scientists. In nature, females of that species are almost exclusively diurnal (active by day)! They leave their burrows in the morning and late afternoon, avoiding the icy steppe nights and their night-time predators.

Interestingly, a wild, non-nursing female spends on average only about an hour a day above ground, in short few-minute food runs - to catch a predator’s eye as little as possible. But when she has young, her foraging time rises 6-8 fold: she has to gather masses of energy to feed her blind, helpless pups.

A master of carrying supplies

Our trademark is the cheek pouches. These are two stretchy pockets on the sides of the head that run under the skin back toward the shoulders. When I fill them with seed, my head can become two - even three - times bigger! They have two ingenious features:

• They’re dry inside - there are no salivary glands in them, so the seeds I carry don’t get damp, spoil or ferment on the way to the pantry.
• They have their own muscle - a special retractor muscle pulls the filled pouch backward so the load doesn’t shift my centre of gravity toward the front of my head. That way, even with full cheeks, I run steadily and can bolt from danger.

And one more fact: hoarding is so deeply wired into us that even pet hamsters do it, despite wanting for nothing.

A strict loner! (the most important lesson)

I have to write this very clearly, because it’s the most common and most dangerous mistake: hamsters are strict loners. That goes for Syrians and for us Djungarians alike. I used to repeat that Djungarians “can be sociable” - now I know that’s a myth, and one that can cost a hamster its life.

Never, under any circumstances, keep two hamsters in one cage - not even siblings from the same litter. Why? As we grow up (roughly between 2.5 and 8 weeks of age), the number of oxytocin receptors in our brains drops sharply. That’s a biological switch that turns off our need for company and turns on strong territoriality.

In the wild we’d simply go our separate ways. In a cage we can’t escape, so a forced companion means chronic stress (which wrecks the immune system) and, sooner or later, brutal territorial fights - often ending in serious wounds or the death of the weaker one. The rule is simple: one hamster = one cage. I write more about setting up a good home in a separate post: how to care for a hamster.

My home is a whole network of tunnels

In the wild, a hamster’s burrow is a real underground castle. Zoologists found that wild Syrian hamsters’ burrows reach from 36 to as much as 106 cm deep. They consist of a vertical entrance shaft, a nesting chamber and a pantry, and the whole tunnel system averages about 2 metres long (and in old burrows, over 9 metres!).

We Djungarians dig burrows up to a metre deep in the wild, usually with several entrances. For winter we plug most of the openings and line the nest with wool and other animals’ fur - keeping the inside at a steady, warm temperature (around 16-17°C), even when the steppe outside is freezing.

That’s why at home we need a thick, stable layer of substrate (ideally 15-20 cm of safe bedding mixed with hay), so we can act on our most important instinct - digging our own tunnels.

One last home tip: respect my scent!

We understand the world mainly through smell. We have special scent glands (Syrians on the flanks, and we dwarves on the belly) that we use to mark our whole surroundings and build our own scent “road map”.

When you clean the whole cage and swap out all the bedding for new, you wipe that map - and we feel completely lost. So whenever you clean, always leave at least a third of the old, clean bedding and mix it in with the new. That way the cage still smells like home.

Now that you know my secrets, take a look at my running stats - and see how I’m doing on the wheel today. 🌙