So many times, we encounter a pair or grouping of companion animals that get along swimmingly — but seem out of place together. Some sleep, eat and play without issue — and even form strong bonds for life.

In an article, "Unlikely friends: Why we love odd animal pairs", the unique friendships between seemingly "odd couples" is illustrated: dogs and cats, a pooch and a chicken — even a baby hippo and a tortoise.

John Wright, Ph.D., a certified applied animal behaviorist and professor of psychology at Mercer University in Macon, Ga., says that in large part, the relationships are genuine. If the animals are both from social species, it's even more likely, of course.

Young animals have a better chance at forming close bonds outside of their species. “If they’re both young, their behavior is what we call ‘plastic,’” Wright says. “It’s very malleable and they’re open to just about any experience and opportunity.”

There are other reasons of course as to why pets or animals who are undomesticated form relationships like this — for example, when tragedy strikes. It's not all that unusual for animals who are orphaned or endure a hardship together, like a natural disaster, to naturally form a comfortable alliance.

Do you have an "odd couple" in your midst? We're eager to learn about the circumstances and see your photos of them.

In keeping with this weeks' theme, "unlikely animal buddies", you're invited to email a photo of your pet to ppsa2mi@gmail.com any time for our weekly Pet Photo Friday feature.

Be sure to include the names of the pets, as well as their age and city or township of residence in your e-mail.

We put the week's photos into a slideshow, publish and promote each Friday here in the Pets section.

In the meantime, check out this video of an Orangutan, Surya — and a Blue Tick hound, Roscoe: a very unlikely pair:

Lorrie Shaw is a regular contributor to AnnArbor.com's pet section. Follow her daily adventures on Twitter.