Scientists have discovered an entirely new shape and it is all over you!

It turns out that your skin cells employ a shape previously unknown to both biologists and mathematicians...

Science Alert: Scientists Have Discovered an Entirely New Shape, And It Was Hiding in Your Cells

Gizmodo: The 'Scutoid' Is Geometry's Newest Shape, and It Could Be All Over Your Body


The original research article: 

Scutoids are a geometrical solution to three-dimensional packing of epithelia

The 'scutoid' shape (d) was named in homage to the scutellum 

 – a posterior portion of the thorax in some insects, which resembles the same mini-triangle shape (e)...  

Paradoxical Arrow of Kokichi Sugihara

The Japanese mathematican Kokichi Sugihara has developed this 3D Arrow model:

You can can get some idea of what's going on here when he picks it up and shows it from above:

ScienceAlert Article on Kokichi Sugihara:

This 3D Optical Illusion Will Make You Question The Shape of Reality  

More 3D Illusions by Kokichi Sugihara:

ScienceAlert: Ambiguous Cylinder Illusion

Many other fascinating illusions can be viewed at the...

Best Illusions of the Year Website 

Creative Sam's Video of the 7 Best Optical Illusions of All Time...

Including the Train Illusion which is somewhat like the dancer that spins two ways...

Strangest Optical Illusions Known to Science

The eye is not merely a window on the world, but a camera and the mind does a lot of processing to produce the world as we see it.  To illustrate this idea, MICHELLE STARR at ScienceAlert has compiled a great set of mindbending optical illusions:

Strangest Otical Illusions Known to Science 
 

Here are the pictures mentioned and further information on each one:

The Dress - Do you see white and gold or blue and gold?

 

Wikipedia Article on the Dress 

The Non-Red Strawberries

Matt Lieberman's Twitter Page on the Strawberries 

The cafe wall illusion

 Illusion Index Page on the Cafe Wall Illusion

 The Illusion Index site also provides information on many other illusions.

Curvature blindness illusion

Original Article by the discoverer:

Curvature Blindness Illusion by Kohske Takahashi 

The Spinning Dancer

Ragu Kattinakere: Spinning Lady Illusion Explained


The Dancing Black Dots

 

Ninio's Extinction Illusion 

Here's why you can't see all twelve black dots 
in this optical illusion 


 The Ambiguous Cylinder Illusion

 

Ambiguous Cylinder Illusion:  How it Works

 

Street Picture Optical Illusion

Two identical street pictures placed side by side suddenly become two different perspectives:

The Daily Mail prepared a short video to show these are indeed exactly the same picture:

 

The informative Daily Mail article goes on to compare this to the famous cafe wall optical illusion where horizontal lines appear to taper or bend:

Can You See It? Incredible Optical Illusion Tricks Your Brain 

 

Michael Bach has a fascinating and informative page on the cafe wall illusion:

Michael Bach on the Cafe Wall Illusion

This page is part of Michael Bach's excellent compendium of visual illusions which is well worth exploring: 

Visual Phenomena & Optical Illusions 

 This illusion is yet another good reminder that the eye is not merely a window.  What we are seeing is in fact a projection within our brains which is influenced by the way our brains work... 

Optical illusions show how we see | Beau Lotto

   

Why can't our extremely complex eyes render simple optical illusions? Surprise, surprise -- it comes back to the brain, which has only evolved to encounter natural stimuli.

Why do we see illusions? - Mark Changizi