19 unlikely animals who became best friends

It’s not unheard of for animals to become quite chummy with members of another species — even with those they would normally consider eating.

Abandonment, trauma, or living together on farms or zoos, all serve as factors in bringing animals together in unexpected ways.

In celebration of National Best Friends Day, we’re taking a look at what happens when opposites attract.

Robert Ferris wrote the original version of this post.

A baby monkey, a lion cub, and tiger cubs play at a Tiger Park in China.

A turtle catches a ride on the back of an alligator in Panama's Summit Zoo.

A monkey bought from an animal trader in Bangladesh spends hours hugging and cuddling this puppy.

A tiger cub and a baby monkey pal around at a zoo in China.

This black swan is feeding these carp at a wildlife park in Shenzen, China.

This dog at a Chinese zoo is acting as a wet nurse for these tiger cubs. Their real mother is too weak to produce milk.

After its own kitten died, this cat started taking care of these puppies, whose mother had been hit by a car.

This brown bear cub wandered into a family's yard in Slovenia, and has since taken to the family dog.

Onward! This mouse is catching a float on this frog in Lucknow, India.

A zoo in Thailand is trying to pair domestic animals like pigs with tigers to bring in more visitors.

These cougar and tiger cubs are quite close with this German shepherd at an Australian veterinarian's house.

This donkey and wolf have become quite close, and even share a pen on the farm where they live in Albania. The friendship draws a lot of attention from the neighbours.

Both abandoned by their owners years ago, this monkey and cat have become playmates at a temple in Thailand. The monkey even checks the cat for lice.

A camel bends over a fence to nuzzle a miniature pig at a zoo in Russia.

A baby hippopotamus cozies up to his adopted 'mother' -- a 120-year-old giant tortoise living in a Kenyan sanctuary.

A monkey helps a parrot get rid of lice at a wild animal park in China.

A dog rests on a buffalo near a river in Pakistan.

A young parrot perches itself on a dog dressed in a hat.

A dog, cat, and mouse pile on at the end of a long day.

Greg Pike's dog Booger, cat Kitty and white mouse Mousie, rest at the end of a day in Bisbee, Arizona, December 24, 2006.

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