There are two types of sumac

This is one of the most interesting things I've found today and it was worth a quick browse (only fast-forwarded a couple times).  Despite having grown up around sumac since my Minnesota childhood, I never learned (or have forgotten) that there is a world of difference between "poison sumac" and "staghorn sumac."  

Upcoming BBC series on evolution

 Very much looking forward to this.  Premieres October 14, 2026 on PBS (NOVA) in the USA.

A cure for anthropocentrism

If you have friends who believe that human beings are the center of everything and humans are the reason for the existence of the universe, suggest to them that they view this video timelapse of history, and note that the entire length and breadth of human existence is condensed into the final cel of the presentation...

Via Neatorama.

Spend three hours with David Attenborough

Via Kottke

"What a wonderful world" (David Attenborough)

My rule of thumb: if it's a David Attenborough video, it's worth blogging.

BTW, if you've never used the "fullscreen" button on a YouTube video [lower right corner], now would be a good time to try it...

Here's a background on the lyrics:

"What a Wonderful World" is a song written by Bob Thiele (as "George Douglas") and George David Weiss. It was first recorded by Louis Armstrong and released as a single in 1967...

The song gradually became something of a standard and reached a new level of popularity. In 1978, Armstrong's 1968 recording was featured in the closing scenes of the first series of BBC radio's cult hit, The Hitchhiker's Guide to the Galaxy, and was repeated for BBC's 1981 TV series of the same. In 1988, Armstrong's recording was featured in the film Good Morning, Vietnam and was re-released as a single, hitting #32 on the US Billboard Hot 100 chart in February 1988. The single charted at number one for the fortnight ending June 27, 1988 on the Australian chart

Via truthdig.

Reposted from 2012 (!) to insert the Louis Armstrong version:

Reposted again in honor of David Attenborough's 100th birthday.

Beavers as landscape architects

There's nothing fundamentally "new" in this video about beavers being reintroduced into Scotland, but the results are impressive.

Related:  

A "rescue beaver" starts building dams inside a house (3-minute video)

Trailcam video compilation of one year activity on a beaver dam in northern Minnesota (6-minute video)

More than you would ever need to know about beaver testicles (re medieval bestiaries)

Vector math demonstration

This is a long (20-minute) video designed to be both entertaining and instructive.  For those in a hurry (which is most of us), here's a reminder that you can find the best parts of videos by viewing the video at You Tube and hovering your mouse over the timeline at the bottom to find the peaks of viewership that typically denote the interesting parts.

Listening to auroras

Well done and quite interesting.  Amazing that in the Sami region of northern Finland there are auroras 150 nights per year.

How to escape from a frog

Apparently the key is to tickle open the cloacal sphincter.

After getting swallowed by a frog, [a water scavenger beetle] can scuttle down the amphibian’s gut and force it to poop — emerging slightly soiled, but very much alive...   A whopping 90 percent of the beetles they swallowed made it out the other end alive, all within six hours of being gulped down...

Beetles of other species didn’t fare quite as well and were excreted as corpses after a couple days in amphibio. Dead Regimbartia took days too, hinting that their living counterparts were actively engineering their great escapes...

Dr. Sugiura thinks Regimbartia beetles may use their legs to brace themselves and crawl through the gut, which can stretch several inches — an arduous journey for a four- or five-millimeter-long beetle. When they reach the end of that tunnel, the insects may be able to tickle open the cloacal sphincter, the ring of muscle that drawstrings the frog’s rear end shut, expelling themselves in a flood of feces.

You learn something every day.  More details at The New York Times.

Related:  When a Murder Hornet becomes a Tasty Meal (with video).

"Brumation" illustrated

"Brumation is a term used to refer to dormancy of reptiles, which is metabolically somewhat different from mammalian hibernation.

The video above shows alligators lying dormant, not in tunnels in mud, but right in a frozen-over pond, with just their nostrils protruding above the ice.

If anyone has even the faintest doubts about the survival capabilities of this superpredator, this video should change your mind.

Reposted from 2018 to add a photo and excerpted text from the Minnesota Star Tribune:

“If the ice is clear, you can sometimes see snapping or painted turtles moving slowly under the ice,” said Jeff LeClere, zoologist and amphibian and reptile specialist with the Minnesota Biological Survey.

“All of Minnesota’s nine species of turtles overwinter aquatically,” he said.

This winter dormancy, called brumation, requires them to be deep enough to avoid being fatally frozen in ice and to slow their metabolism drastically to conserve energy. Most don’t move at all once this turtle equivalent of hibernation begins. It also minimizes their need for oxygen, which they absorb from the frigid water through a process called cutaneous respiration...

Softshell turtles tend to bury themselves about an inch beneath sand, silt or gravel, while other species sidle under logs or rocky nooks. Map turtles like to congregate along the wing dams, which are rock structures along navigation channels of the Mississippi River, LeClere said. Having shelter can lessen the threat of winter predators such as otters...

Some turtles, such as painted or snapping turtles, simply seek the right depth at the bottom of a lake or pond. They may congregate in areas where natural springs or a lack of shade encourages quicker melting — with vital access to sunshine and food — in the spring.

The embedded image is a screencap from a video posted at this Field Ecology Blog.

Counting asteroids

I'll never forget the moment Carl Sagan described the number of stars as being greater than all the grains of sand on all the beaches of Earth.  This video provides an equivalent perspective on the number of asteroids in the asteroid belt.  The successive zoom-outs are impressive, but especially the final image showing how little of the belt was sampled for the data.

"All dams are temporary"

Interesting engineering video - especially the demonstration of sediment deposition using colored sand.  Not really new info, but worth a browse because it's well illustrated and concisely narrated (14 minutes, plus a relevant advertisement at the end).

Ocean currents visualized

Very cool five-minute animation if you can view fullscreen on desktop rather than phone.  Interesting how the Pacific equatorial current smashes into the Galapagos.  Wish they had shown the Southern Ocean in some detail.  Via Miss Cellania, where there is also a humorous photo of Riley and Albert.

Hurricane aftermath in a mountain forest

Posted for my family in Asheville, whose home avoided major damage, but whose community is devastated.

And I'll add this video of a lake covered with debris:

What happens to the ecosystem of a lake in that situation?  One would have to assume that there are no resources available to clean the lake by removing the debris, which will start to decay.  The light and oxygen levels in the water will be inadequate for aerobic life.  The stench will probably be incredible.  Recreation and tourism will be at a standstill for years.

Addendum:  Amazing improvement in the lake since I posted this, thanks to the Army Corps of Engineers.  See the video at the link in the comment by reader Marc B.

Five minutes worth watching...

... if you have a love or fascination for the natural world.  This video from the Monterey Bay Aquarium Research Institute documents the discovery of a new species.  For those in a hurry, a written summary is available at Live Science.

Water ice... on MERCURY !!

The process of writing posts for TYWKIWDBI keeps driving me to various corners of the internet, where I encounter things that I not only didn't know, but couldn't even imagine.  As a child I was told that one of the special features of our planet was the availability of abundant water.  Later I came to understand via reading (and movies) that there are extraterrestrial "water worlds," including within our own solar system (Europa has more water than Earth does).

In 2009 I blogged Surprising quantities of water on the moon!, adding the exclamation point to the title.  Earlier this year it was Huge quantities of water ice detected on Mars, without the exclamation point because earlier studies of Mars geology had suggested that the planet had once had abundant water.

None of that previous knowledge prepared me for the shock of reading recently that NASA has found good evidence for water ice on the planet Mercury.  

"The yellow regions in many of the craters mark locations that show evidence for water ice, as detected by Earth-based radar observations from Arecibo Observatory in Puerto Rico. MESSENGER has collected compelling new evidence that the deposits are indeed water ice, including imaging within the permanently shaded interiors of some of the craters, such as Prokofiev and Fuller."

I have embedded above an hour-long video from the NASA channel presenting the recent conference summary.   Knowing that most of the readers of TYWKIWDBI fall into the TLDR category, here is my oversimplification.

It begins with the realization that although Mercury as a whole is incomprehensibly hot, it is not uniformly hellish.  This scan of a polar region shows temperatures ranging from 50 degrees Kelvin (-223 Celsius, -369 Fahrenehit) to 500 degrees Kelvin (227 Celsius, 440 Fahrenheit).  The temperature at which water freezes would be the 273K yellow shade.  The blues below that are subfreezing.

Point #2 is that some areas in craters are in permanent shadow from incident light:

Water would arrive via the impact of icy comets or meteors -

The non-water dust/rocks in the impacts would provide a modicum of cover for the ice, delaying its sublimation.

Recent instrumentation has shown the depth of water ice in these craters

I just speeded through the video myself while taking the screencaps, so I need to go back and listen in detail for the nuances.  (on second speed-through I heard comment that liquid water is still impossible on Mercury because the absence of an atmosphere would result in only meta-stable liquid form that would immediately volatilize.)

I'm just totally gobsmacked, especially by the cosmic implication that all this water is flying all around the universe and crashing into planets that have moderate temperatures, and that this has been going on for billions of years (see early universe link below), which raises in my estimation the likelihood of water-based life elsewhere in the universe close to certainty.

You learn something every day.

See also:  Water was plentiful in the early universe and Origin of water on earth.

Homo Naledi

This video is concise (12 minutes), informative, and presented in a professional manner.  New information for me and perhaps some readers - definitely worth a view if the history of modern humans is of interest to you.  A tip of the blogging cap to my cousin Otrastan for sending it to me.

Incredible amounts of beach glass

No need to watch the entire video, but worth browsing for sea glass collectors.  I have on occasion spent a couple hours on the shore of Lake Superior searching, and was happy to find a handful of specimens.  This beach in St. Kitts is unbelievable.

MSICS to correct "preventable blindness"

A TEDX talk in which an American ophthalmic surgeon explains how "manual small-incision cataract surgery" (MSICS) with a 50c scalpel is an effective substitute for the standard American-style laser-guided procedure costing $2,000 for the treatment of mature cataracts.  The worldwide statistics are staggering: cataracts in 200,000,000 people causing half of all worldwide blindness, with each untreated case also impairing the life of associated caregivers.

Concise, well-spoken, and definitely worth 15 minutes of your time, IMHO.

How quickly can a chicken cross the road? Updated.

A very interesting and entertaining portrayal of the speeds of various birds on land and in the air.  There are lots of surprises (vulture, pheasant, pigeon!)  Go ahead and click the fullscreen icon; life is too short not to enjoy things to the max.

Reposted from last year to add this comparison video of terrestrial animals:

Via Neatorama, of course.   From the video site you can also click to a similar video of aquatic life.