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Kenjamoto // CC BY 3.0
Kenjamoto // CC BY 3.0

Watch This "Impossible Object" Dovetail Cube Puzzle

Kenjamoto // CC BY 3.0
Kenjamoto // CC BY 3.0

This puzzle is devious. Externally, it looks like a cube with dovetails cut on four sides—which should be impossible. Dovetail joints are normally cut to join two planes to each other, like the front of a drawer with its side. It shouldn't be possible to cut dovetails across four interlocking planes...so how does this puzzle do it?

You can just skip ahead to the video below if you'd like a visual explanation—or I'll spoil it for you now. In short, the "impossible dovetail" relies on a hidden set of diagonal cuts that allow the puzzle to slide apart diagonally. There's often a pin or other fastening mechanism to prevent an accidental slide, making the joints appear firm and fast until you press it.

The logic of this puzzle plays on our assumptions about how dovetail joints work. Because these joints typically prevent motion in two planes, those are the planes we look at. Is it possible to pull the top off the puzzle? Nope! How about side-to-side? Impossible! By adding a dimension to the puzzle, the solution is revealed in that extra dimension as well—you've got to slide the pieces apart diagonally. The joints, of course, aren't impossible...it's our assumptions about how dovetail joints are cut that are incorrect.

In this video, "Mr. Puzzle" walks us through the solution to a wooden version of the puzzle (the solution starts at 1:52). Have a look:

If you're curious how this thing was made, here's a similar project by Clickspring, but machined out of aluminum. Behold:

If you'd like to make your own puzzle, free plans are online for a wooden version (requires a hand saw, coping saw, and chisel) as well as a plastic version (requires 3D printer).

(Image by Kenjamoto // CC BY 3.0.)

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NOAA, Wikimedia Commons // Public Domain
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Animals
Watch the First-Ever Footage of a Baby Dumbo Octopus
NOAA, Wikimedia Commons // Public Domain
NOAA, Wikimedia Commons // Public Domain

Dumbo octopuses are named for the elephant-ear-like fins they use to navigate the deep sea, but until recently, when and how they developed those floppy appendages were a mystery. Now, for the first time, researchers have caught a newborn Dumbo octopus on tape. As reported in the journal Current Biology, they discovered that the creatures are equipped with the fins from the moment they hatch.

Study co-author Tim Shank, a researcher at the Woods Hole Oceanographic Institution in Massachusetts, spotted the octopus in 2005. During a research expedition in the North Atlantic, one of the remotely operated vehicles he was working with collected several coral branches with something strange attached to them. It looked like a bunch of sandy-colored golf balls at first, but then he realized it was an egg sac.

He and his fellow researchers eventually classified the hatchling that emerged as a member of the genus Grimpoteuthis. In other words, it was a Dumbo octopus, though they couldn't determine the exact species. But you wouldn't need a biology degree to spot its resemblance to Disney's famous elephant, as you can see in the video below.

The octopus hatched with a set of functional fins that allowed it to swim around and hunt right away, and an MRI scan revealed fully-developed internal organs and a complex nervous system. As the researchers wrote in their study, Dumbo octopuses enter the world as "competent juveniles" ready to jump straight into adult life.

Grimpoteuthis spends its life in the deep ocean, which makes it difficult to study. Scientists hope the newly-reported findings will make it easier to identify Grimpoteuthis eggs and hatchlings for future research.

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WWF
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Animals
Watch an Antarctic Minke Whale Feed in a First-of-Its-Kind Video
WWF
WWF

New research from the World Wildlife Fund is giving us a rare glimpse into the world of the mysterious minke whale. The WWF worked with Australian Antarctic researchers to tag minke whales with cameras for the first time, watching where and how the animals feed.

The camera attaches to the whale's body with suction cups. In the case of the video below, the camera accidentally slid down the side of the minke whale's body, providing an unexpected look at the way its throat moves as it feeds.

Minke whales are one of the smallest baleen whales, but they're still pretty substantial animals, growing 30 to 35 feet long and weighing up to 20,000 pounds. Unlike other baleen whales, though, they're small enough to maneuver in tight spaces like within sea ice, a helpful adaptation for living in Antarctic waters. They feed by lunging through the sea, gulping huge amounts of water along with krill and small fish, and then filtering the mix through their baleen.

The WWF video shows just how quickly the minke can process this treat-laden water. The whale could lunge, process, and lunge again every 10 seconds. "He was like a Pac-Man continuously feeding," Ari Friedlaender, the lead scientist on the project, described in a press statement.

The video research, conducted under the International Whaling Commission's Southern Ocean Research Partnership, is part of WWF's efforts to protect critical feeding areas for whales in the region.

If that's not enough whale for you, you can also watch the full 13-minute research video below:

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