This series of photos purportedly showing a crow landing on and riding atop the back of an eagle in flight has left social media in fascination.

The photographs were captured by Phoo Chan, a skillful California-based photographer whose photos have been featured by National Geography.

Chan explained on his 500px page:

"Crows are known for aggressively harassing other raptors that are much bigger in size when spotted in their territories, and usually, these 'intruders' retreat without much fuss."

"However, in this frame, the crow did not seem to harass the bald eagle at such proximity, and neither did the bald eagle seem to mind the crow's presence invading its personal space."

"What made it even more bizarre was that the crow even made a brief stop on the back of the eagle as if it was taking a free scenic ride and the eagle obliged."

It's not the first time such an incident has been spotted. A similar animal-hitching image that featured a baby weasel riding a woodpecker left many viewers questioning the authenticity.

Though some commenters discredited the photos as depicting an impossible activity, Kelvin McGowan, a biologist specializing in the study of crow behaviors, confirmed that the photographs were indeed real.

McGowan said:

"This would be kind of like a dog chasing a car and jumping up."

"Dogs always want to catch the car, but they never know what they'd do if they get it."

Chan's photos may depict an impossible or one-in-a-million scene, but other images of crows riding eagles abound online. In 2012, a Cater News photographer, Hyeongchol Kim, captured a similar occurrence in South Korea.

Kim revealed:

"I saw the crow flying towards the much bigger eagle, and prepared myself to capture the fight on camera."

"The bird just hovered above the eagle for a few seconds – and then appeared to just latch onto his back."

"The eagle didn't seem to mind at all — I think they must have been friends."