Hans Rosling clarifies world demographics

YouTube link.

I have featured Hans Rosling on a number of previous posts at TYWKIWDBI because I truly admire his style of presentation.  The best hours of my academic life were spent behind or beside the podium in front of an classroom full of students, so I'm supersensitive to the nuances of lecturing.  This guy has all the skills.  He is recognized as a wizard at portraying otherwise-dry statistics in comprehensible visual forms (see his superb TED talk on the developing world).  In addition his stage presence is captivating, and his use of English (as a second language) is excellent.

I'm not blogging today, but I wanted to put this up for you.  I know everyone's life these days is one continuous TL;DR, but take my word for it, if you are interested in the world beyond your doorstep, this video is worth 15 minutes of your time.  Or at least the first five, and then see if you can stop.

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A global rainfall/snowfall map

YouTube link.

Created by NASA: "The map covers more of the globe than any previous precipitation data set and is updated every half hour, allowing scientists to see how rain and snow storms move around nearly the entire planet.... What this visualization shows so clearly is that all precipitation is interrelated all around the globe."

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A new video series from The American Museum of Natural History

YouTube link.

The American Museum of Natural History offers incomparable resources for anyone seriously interested in the natural world.  They are now producing a series of videos designed to highlight their mission and their astonishing array of source material.

I've embedded above the fourth video in the series - "Skull of the Olinguito" - which explains how new species can be discovered in archived specimens:

Considering the number of specimens collected during the trip, it’s little wonder that the olinguito—Mammal #66573, a raccoon relative originally identified as a kinkajou—spent nearly 90 years on the Museum’s shelves before being described as the new species Bassaricyon neblina in 2013.

The third video in the series was Six Ways to Prepare a Coelacanth.  The previous two, and subsequent ones to be released on a monthly basis, are available here.  These are concise, interesting, high-production-quality videos tailored for anyone with an interest in the natural world.

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The other side of the moon

YouTube link.

It's not dark.  And there don't appear to be any Nazi encampments - at least on the surface.

Awesome imagery created by NASA using data from the Lunar Reconnaissance Orbiter.

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"Deflagration" demonstrated by "fire-breathing" using cornstarch

YouTube link.

The video and the source link at fuckyeahfluiddynamics casually suggest "not to try this at home."  I would like to emphasize this point, not because of the fire risk, but because of the posibility of asphyxiation.  Especially in a child, a mouthful of cornstarch poses a potential risk to the airways if it is accidentally inhaled. 

btw: Deflagration (Lat: de + flagrare, "to burn down") is a term describing subsonic combustion propagating through heat transfer; hot burning material heats the next layer of cold material and ignites it. Most "fire" found in daily life, from flames to explosions, is deflagration.

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Norwegian fjords invaded by "monster jellyfish"

YouTube link.

As reported in The Local (Norwegian news in English):

The innermost arm of the Trondheimsfjord now holds an estimated 40,000 tonnes of the helmet jellyfish, only a few years after the fiery red peril first appeared in its waters.

"We took up 3.5 tons of monster jellyfish in under ten minutes," he said. "There was a tremendous amount more than we expected. The trawler winch was just about to give way."

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How to play with supercooled water at home

YouTube link.

This reminds me of how my mother's family used to make ice cream on the farm, with what presumably was a supercooled churn.

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A fox dives into DEEP snow - update #2

I first posted this video several years ago, but I find it to be endlessly fascinating.  A hat tip to 22 words for reminding me.

Addendum:  And a hat tip to several readers for pointing out that this diving skill has some intriguing scientific roots, nicely summarized at one of my favorite science blogs, Not Exactly Rocket Science:

Jaroslav Červený has found that when red foxes pounce, they mostly jump in a north-easterly direction. He thinks that they’re using the Earth’s magnetic field to hunt.

Červený spent over two years studying wild red foxes in the Czech Republic, with the help of a 23-strong team of wildlife biologists and experienced hunters. The team recorded almost 600 mousing jumps, performed by 84 foxes at a wide variety of locations and times.

They found that foxes strongly prefer to jump in a north-easterly direction, around 20 degrees off from magnetic north. This fixed heading was important for their success as hunters. They were more likely to make a kill if they jumped along their preferred axis, particularly if their prey was hidden by high cover or snow. If they pounced to the north-east, they killed on 73% of their attacks; if they jumped in the opposite direction, they success rate stayed at 60%. In all other directions, only 18% of their pounces were successful...

Červený suggests that a red fox could use the Earth’s magnetic field as a “rangefinder”, to estimate the distance to its prey and make a more accurate pounce. This targeting system works because the Earth’s magnetic field tilts downward in the northern hemisphere, at an angle of 60-70 degrees below the horizontal. As the fox creeps forward, it listens for the sound of a mouse. It’s searching for that sweet spot where the angle of the sound hitting its ears matches the slope of the Earth’s magnetic field. At that spot, the fox knows that it’s a fixed distance away from its prey, and it knows exactly how far to jump to land upon it...

This totally fascinating ability is discussed in more detail at the link, and illustrated here -

- from an article in Nature.  Evolution is so amazing.

Reposted from 2011 to add this video of a domestic dog pouncing the shadow of a bouncing baby:

YouTube link.

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