Look Closely at This Footstep Illusion

The best optical illusions are the ones you can try at home. Take the footstep trick below: All you need to recreate it is a white sheet of paper with black stripes and a transparent film sheet marked with yellow and blue blocks. It may look simple, but move the film across the page and the colored shapes will appear to shuffle forward like tiny footsteps.

The illusion, recently shared by The Kid Should See This, is the creation of Akiyoshi Kitaoka, a professor with the psychology department at Kyoto’s Ritsumeikan University. He explained the mechanism at work in a paper he published with psychology professor Stuart Anstis in 2015 [PDF].

According to the report, the colored blocks need to be two times the width of the black stripe and either light (like the yellow ones) or dark (the blue ones) for the trick to pay off. The illusion is all about contrast, so the colors are essential. The authors explain:

“When the dark blue squares lie on white stripes, they have high contrast (dark vs. white) and they appear to speed up momentarily. When they lie on black stripes, they have low contrast (dark vs. black) and they appear to slow down. The opposite is true for the light yellow squares.

Consequently, the squares appear to go faster and slower in alternation, like a pair of walking feet.”

The brain takes all sorts of shortcuts when it comes to perceiving color, and most of the time this goes unnoticed. But when an artist knows how to exploit this it can lead to some mend-bending tricks, like this image from Akiyoshi Kitaoka in which three colors appear to be four. Check out more of Kitaoka's psychedelic illusions on his webpage.

[h/t The Kid Should See This]

University of York
Stones, Bones, and Wrecks
UK Archaeologists Have Found One of the World’s Oldest 'Crayons'
University of York
University of York

A prehistoric chunk of pigment found near an ancient lake in England may be one of the world's oldest crayons, Colossal reports. The small object made of red ochre was discovered during an archaeological excavation near Lake Flixton, a prehistoric lake that has since become a peat wetland but was once occupied by Mesolithic hunter-gatherers. Though it’s hard to date the crayon itself, it was found in a layer of earth dating back to the 7th millennium BCE, according to a recent study by University of York archaeologists.

Measuring less than an inch long, the piece of pigment is sharpened at one end, and its shape indicates that it was modified by a person and used extensively as a tool, not shaped by nature. The piece "looks exactly like a crayon," study author Andy Needham of the University of York said in a press release.

A pebble of red ochre thought to be a prehistoric crayon
University of York

The fine grooves and striations on the crayon suggest that it was used as a drawing tool, and indicate that it might have been rubbed against a granular surface (like a rock). Other research has found that ochre was collected and used widely by prehistoric hunter-gatherers like the ones who lived near Lake Flixton, bolstering the theory that it was used as a tool.

The researchers also found another, pebble-shaped fragment of red ochre at a nearby site, which was scraped so heavily that it became concave, indicating that it might have been used to extract the pigment as a red powder.

"The pebble and crayon were located in an area already rich in art," Needham said. "It is possible there could have been an artistic use for these objects, perhaps for coloring animal skins or for use in decorative artwork."

[h/t Colossal]

Jeff J Mitchell/Getty Images
Tour the National Museum of Scotland From Home With Google Street View
Jeff J Mitchell/Getty Images
Jeff J Mitchell/Getty Images

Google's Street View technology can be used to view some amazing art, whether it's behind the walls of the Palace of Versailles in France or the Guggenheim Museum in New York. As the BBC reports, the National Museum of Scotland in Edinburgh is the latest institution to receive the virtual treatment.

The museum contains items tracing the history of the world and humanity. In the Natural World galleries, visitors will find a hulking Tyrannosaurus rex skeleton and a panorama of wildlife. In the World Cultures galleries, there are centuries' worth of art and innovation to see. The museum's permanent galleries and the 20,000 objects on display can all be viewed from home thanks to the new online experience.

Users can navigate the virtual museum as they would a regular location on Street View. Just click the area you wish to explore and drag your cursor for full 365-degree views. If there's a particular piece that catches your interest, you may be able to learn more about it from Google Arts & Culture. The site has added 1000 items from the National Museum of Scotland to its database, complete with high-resolution photos and detailed descriptions.

The Street View tour is a convenient option for art lovers outside the UK, but the museum is also worth visiting in person: Like its virtual counterpart, admission to the institution is free.

[h/t BBC]


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