How many horses can you see in this mind-boggling optical illusion?

A mind-boggling optical illusion that appears to show horses on a mountain top has caused a row between the painter and scientists — but who’s right?

Optical illusions typically cause a stir online but a recent painting said to show several horses on a mountain top has caused a feud between its creator and a bunch of scientists — but how many can you see?

Bev Doolitte’s portrait of five patch-skinned horses standing together on a snow ledge has been a mainstay on the National Institute of Environmental Health Services’ (NIEHS) website for a while now.

In it, what appears to be four white and brown horses and a foal are bunched together and blend into the brown rock and snowy background, giving the picture an optical illusion.

But scientists say Doolitte’s image actually has seven horses and not five, as its creator claims.

According to the group, the picture is of made of seven horses including some partial horses like a horse head and rear.

If you can’t see seven then maybe this humorous note from one of the NIEHS’ own scientists might help.

” I see one on the left looking out, and in the middle four faces are clustered close together — in that group the brown nose of one (second from left) covers the right side of the face of the one crouched lowest.

“To the right is a small horse standing sideways, and above it is the rear of the seventh. Unless I am hallucinating.”

If you still can’t see seven then rest assured by the fact you’re among the many who believe the real number shown in the picture to be five.

In December, an optical illusion was published that makes straight lines appear curved has left people feeling “dizzy”.

The strange visual puzzle was shared by genomics researcher Laurel Coons and features a chequered pattern with green lines outlining grey squares.

She proceeded to challenge the public to spot where the curved lines were located among several straight equivalents.

But the illusion quickly went viral on social media after users were left perplexed by the “trippy” image with the task appearing more difficult then it first appeared.

This story originally appeared on The Sun and was reproduced here with permission.