Cat owners who leave empty boxes lying around know that eventually the box will contain a cat. What makes a simple cardboard box so enticing to your cat? Scientists don’t know exactly why cats are attracted to boxes but have several theories.

One is the advantage a box provides to stalk prey – whether it be a fellow cat or human or something else that attracts their attention. Cats are ambush predators and boxes provide great hiding places for stalking prey. In the wild seeking out confined spaces is instinctual behavior for cats and lets them both hide from predators and stalk prey.

There’s also a boatload of behavioral research on cats focused on environmental enrichment. The research has found that cats find both comfort and security from enclosed spaces. Cats that are stressed can be profoundly affected by the security of a box in which to hide.

Those who study animal behavior, such as ethologist Claudia Vinke of Utrecht University in the Netherlands, have found that shelter cats in particular that are given hiding boxes while introduced to a shelter suffer less stress than cats without the boxes. The cats with boxes got used to their new surroundings faster, were far less stressed early on, and were more interested in interacting with humans.

This seems natural considering that cats don’t handle conflict well. Their response is to go hide rather than confront whatever the stressor is. In the wild cats retreat to tree tops, dens, or caves while our pet cats find comfort in a shoe box.

My cat Kali is quite shy so any new or odd noise will send her under her cat stoop, which has a blanket draped over it like a tent. There’s just enough of an opening for her to peer out and see what’s going on while feeling safe and secure.

Another possible reason for cats liking boxes is that they’re cold and boxes provide the insulation they need to feel warm.  Corrugated cardboard is a great insulator and confined spaces force cats to curl up which then helps them to preserve body heat.

According to a 2006 study by the National Research Council, the thermoneutral zone for a domestic cat is 86 to 97 degrees Fahrenheit.  That’s the range of temps in which cats are “comfortable” and don’t have to generate extra heat to keep warm. That range is also 20 degrees higher than ours, which explains why it’s not unusual to see our cat Mia curled up close to the gas fireplace. To us it’s uncomfortably hot to be that close but she loves the heat.

And, finally, those insulated, stress-relieving, comfortable boxes also provide a safe place for cats to nap. Given that felines sleep for up to 20 hours a day, that’s a pretty big deal. Who wants a cranky cat that can’t get enough sleep?