Siberian jays and woodpecker in Sweden


This November 2912 video is about Siberian jays, and a grey-headed woodpecker, in Sweden.

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United States pro-peace woman interviewed in Britain


This 12 July 2017 video from the Stop the War coalition in Britain says about itself:

Medea Benjamin: Trump, The Special Relationship & The ‘War on Terror

Known for her fearless protests in the face of US presidents and author of the books Drone Warfare and Kingdom of the Unjust, Medea Benjamin, has become one of the 21st century’s most prominent activists. Tune in and listen to her thoughts on Trump, the “special relationship“, arms sales to Saudi Arabia & the “War on Terror

Ant-mimicking jumping spiders protect themselves


This 2012 video is called Ant mimic jumping spider – Japan Myrmarachne.

From Cornell University in the USA:

Walking like ants gives spiders a chance

July 14, 2017

Summary: To avoid being eaten, some jumping spiders pretend to be ants, a new study has found. Protective mimicry is a remarkable example of adaptive evolution: Moths can be colored like butterflies and grasshoppers may look like tiger beetles. While most mimicry studies focus on traits like color and shape, the researchers in this work used multiple high-speed cameras and behavioral experiments to pinpoint how the spider’s movements mimic ants.

Humans aren’t the only actors on the planet. To avoid being eaten, some jumping spiders pretend to be ants, according to Cornell University research published in Proceedings of the Royal Society B.

Ants are aggressive at defending themselves: They are well-armed with bites, stings and formic acid. Ant-mimicking jumping spiders — Myrmarachne formicaria — in contrast, can’t do much more than run on their eight legs when attacked. Not surprisingly, insect predators tend to prefer spiders over ants, so appearing to be an ant confers significant protection.

Protective mimicry is a remarkable example of adaptive evolution: Moths can be colored like butterflies and grasshoppers may look like tiger beetles. While most mimicry studies focus on traits like color and shape, the researchers used multiple high-speed cameras and behavioral experiments to pinpoint how the spider’s movements mimic ants.

Ant-mimicking spiders walk using all eight legs but pause frequently to raise their forelegs to mimic ant antennae. When walking, they take winding trajectories of about five to 10 body lengths, which made them look like ants following pheromone trails. While the researchers could see what the spiders were doing thanks to high-speed cameras, many potential predators have slower visual systems, so that to them the mimics appear to be moving just like an ant would.

The researchers note that the findings “highlight the importance of dynamic behaviors and observer perception in mimicry.”