You may have seen a video on the internet involving a bird that looks like a gorilla.

'Gorilla crow'

The video first surfaced on Twitter on June 20, 2019, and was uploaded by someone in Nagoya, Japan.

He claimed to have gotten a shock from the sight:

朝から衝撃をありがとう。
心臓に悪い、 pic.twitter.com/fDlOGiumD6

— LIWJATAN DEL REY (@keita_simpson) June 20, 2019

The bird was spotted striking a peculiar pose, which made it appear like a tiny gorilla.

Here's a closer look at the bird, which has been identified to be a crow:

Since the video went viral, the bird has been dubbed "gorilla crow".

Just an optical illusion

In response to the video, some people have attempted to explain this curious optical illusion.

One crow researcher on Twitter claimed that it is a "large-billed crow", which explains why its face is slightly out of proportion in comparison to its body.

There’s a very strange (uncredited) video of crow making the rounds on reddit. Here’s the deal. First, this is a large-billed crow, which is why the face is looking a little out of proportion. pic.twitter.com/LUYuMimvAp

— Kaeli Swift, Ph.D. (@corvidresearch) June 22, 2019

The researcher also suggested that the crow was sunning itself.

When crows are sunning, they "drop their wings" and "cock their tails". At a certain angle, it appears that the legs and tail are missing.

What it’s actually doing is sunning itself. When birds sun they drop their wings and cock their tails. At the right angle that could obscure the legs and tail making it look like they’re missing.

— Kaeli Swift, Ph.D. (@corvidresearch) June 22, 2019

Here's a helpful illustration:

自分を納得させるために絵を描いてみたけど合ってますかね pic.twitter.com/af5uYEUrGW

— Kihara (@_S4M2) June 22, 2019

Another crow researcher added that the crow could possibly be "emaciated", as tired or hungry birds often droop their wings as well.

Sunning is a possibility. Another is that the bird might be emaciated. The keel looks highly pronounced here, which could indicate loss of breast muscle. Tired or hungry birds also often droop their wings down like this.

— Dave Slager (@dlslager) June 23, 2019

Not a freak of nature then, phew.

Top photo via video screengrabs, Twitter/keita_simpson