A botanical mystery

One of the most pernicious tendencies in human thought is our arrogance.  The attitude that we know all there is to know, understand the universe, have it all figured out, has led to more oversights, blunders, and outright idiocy than anything else I can think of.

What's striking is how often our intuition about things turns out to be wrong.  Consider, for example, the following question: of all the species currently alive on Earth, what percent of them are known to science -- identified, observed, collected, or studied?

The best estimate we have, from a 2011 study that appeared in PLoS Biology, blew my mind, and as a 32-year veteran of teaching biology, I was ready for an answer lower than my expectation.  You ready?

Fourteen percent.

The study estimated the total number of species on Earth at 8.7 million, 86% of which are unknown to science.  This is staggering.  We are fooling around with our climate and ecosystems, bulldozing our way through our own living space, and potentially destroying millions of species we didn't even know existed.

To be fair, our ignorance about the organisms we share the planet with is at least in part not our fault.  If, like me, you live in a comfortable home with amenities and no particular need to venture off into the wilderness, it would be easy to think that our familiar surroundings are all there is.  The truth is a little humbling, and far more interesting.  I remember my first trip to Hawaii, back in 2003, when we spent our time on the lovely island of Kauai.  While we were there, we took a boat trip out to the Na Pali Coast, a stunning terrain that has a few narrow sandy beaches, but almost immediately beyond them wrinkles up into mountains that are in places damn near vertical.

Carol and I at Na Pali

The guide on the boat told us something that I found astonishing; large parts of Waimea Canyon and Koke'e Parks, which lie inland from Na Pali, are completely unexplored.  Not only is it too steep for roads to be built, you can't even land a helicopter.  Hiking might be possible, but it's densely forested.  The combination has made the interior of these parks one of the few places in the United States where we can say with fair confidence that no human being has ever stood.

Add to that the fact that even more unexplored than some of the remote terrestrial regions are the deep oceans.  I've heard it said we know more about the terrain of the Moon than we do about the floor of the deep ocean -- I don't know if that's true, but it sure sounds plausible.

I'd like to consider, though, a more positive thought; that our lack of knowledge of other species on Earth means there is a lot out there that we could still potentially learn.  And sometimes that happens through unexpected channels.  In fact, the reason this whole topic comes up is because of an article last week in Atlas Obscura about a British botanist and biological artist named Marianne North (24 October 1830-30 August 1890), who traveled all over the world painting native plants in intricate detail -- and who captured an image of at least one plant nobody could identify.

The painting in question was made in Sarawak, one of two states of Malaysia that are on the island of Borneo.  Sarawak is a bit like Kauai; inhabited at the perimeter, but with an inland of rugged terrain and dense, nearly impenetrable forest.  Well, this kind of thing didn't stop North, who made some exquisite paintings of plants in Sarawak, including this one:

[Image is in the Public Domain]

The plant with the blue berries was unidentified -- some botanists thought it might be a member of the tropical genus Psychotria (in the coffee family, Rubiaceae).  But something about that didn't ring true.  None of the 1,582 catalogued species of Psychotria has blue berries -- all the known ones are red or pink -- and the arrangement of the leaves didn't look quite right.  So either (1) this one was an anomaly, (2) North painted the plant inaccurately, or (3) the identification was wrong.

Option (1) was a little far-fetched, but not outside the realm of possibility.  Option (2) struck most knowledgeable people as outright impossible; North was known for her absolute painstaking attention to minute detail.  So botanist and illustrator Tianyi Yu decided (3) had to be correct.  But how to find a single species of plant in an overgrown wilderness on the island of Borneo, which had avoided detection by other scientists for over a century?

Yu had a brainstorm; maybe it hadn't completely flown under the radar.  He decided to spend some time in the herbarium at Kew Gardens.  If you are ever in England, Kew is a must-see; it is home to one of the most amazingly complete collection of plants in the world, and is also stunningly beautiful, especially in spring and summer.  The herbarium contains collections of preserved plants stretching back to its founding in the middle of the nineteenth century, and currently houses over eight million specimens.

So saying it was a needle in a haystack is an understatement.  Yu had one thing going for him; North had been not only a meticulous artist, she was also conscientious about writing down where her paintings had been made.  This one was labeled "Matang Forest, Sarawak," and since the Kew specimens are catalogued not only by species but by location, it significantly narrowed down Yu's search.

And he found it.  A sprig of it was collected in 1973 and sent back to Kew, but was unidentified.  Yu studied both the specimen and North's painting, and concluded that it was a member of the genus Chassalia -- also in Rubiaceae, so the guess of Psychotria hadn't been that far off.

Further analysis by botanists confirmed Yu's surmise.  As the person who identified it as a previously-unrecorded species, Yu was given the honor of naming it.

And last year, it went down in the taxonomic records as Chassalia northi, in recognition of Marianne North's contributions to the field of botany.

So out there on the island of Borneo is a little shrub with white flowers and blue berries that we now have a name for because of a nineteenth-century adventurer/scientist/artist, a happenstance collection from 1973, and a diligent modern botanist determined to put the pieces together.  Just showing that we can still pick away at the sphere of our own ignorance -- but only if we are first willing to admit that there is a lot we still don't know about the world we live in.

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A time capsule in amber

Today we're going to turn away from the generally atrocious stories in the news and focus on some science that's just plain cool.

You probably all know by now that bird are dinosaurs.  Not that they're related to, or descended from, dinosaurs; they are dinosaurs, belonging to the clade Dinosauria of the Phylum Chordata, specifically a group called the saurischians ("lizard-hipped" dinosaurs).  As such, they're cousins to such behemoths as Tyrannosaurus rex, and also velociraptors, made famous by Jurassic Park.  (Nota bene: although pack hunters, they probably weren't smart enough to get out of a locked freezer.)

So think of that next time you see a sparrow flitting about.  That, my friends, is a flying dinosaur.

This comes up because of the recent discovery of a bird leg preserved in amber.  These sorts of fossils are pretty uncommon, so this one has really stirred the paleontologists up.  It dates to about 98 million years ago, putting it dead center in the Cretaceous Period, which ended with a (literal) bang, the double whammy of a huge meteorite collision (Chicxulub) and a stunningly huge volcanic eruption (the Deccan Traps).

This bird, however, was comfortably positioned 42 million years before any of that nasty stuff happened, although that probably wasn't much consolation when he got mired in tree sap and probably either starved or was picked off by a predator, leaving his leg encased for us to find.  Here's the fossil itself:

And a reconstruction by artists, courtesy of the journal Current Biology:

I do have to wonder a little about the reconstruction, given that this species -- christened Elektrornis chenguangi ("elektron" is Greek for "amber") -- belongs to a group called enantiornithines.  Speaking of interesting derivations; enantiornithine is Greek for "mirror-image bird," because the group had a reversed orientation of the shoulder articulation.  Anyhow, the reconstruction seems to ignore one of the most prominent features of this group to our 21st-century picture of what a bird should look like:

They had teeth.

Not great big nasty pointy ones, no, but teeth nonetheless.  Here's a skull of a different enantiornithine, Bohalornis:

[Image licensed under the Creative Commons Fanboyphilosopher (Neil Pezzoni), Bohaiornis skull reconstruction, CC BY 4.0]

So a little more ferocious-looking than the artist's reconstruction might indicate.

The weirdest thing about Elektrornis specifically is that it had a greatly elongated middle toe (which you can see not only in the reconstruction but in the photograph of the fossil itself).  What it was used for is unknown, although the team that did the research -- Lida Xing, Jingmai K. O’Connor, Luis M. Chiappe, Ryan C. McKellar, Nathan Carroll, Han Hu, Ming Bai, and Fuming Lei, of the China University of Geosciences, the Chinese Academy of Sciences, the Natural History Museum of Los Angeles, the University of Regina, and the University of New England (Australia) -- speculate that it probably was an adaptation for feeding or for grasping.

Not, probably, for flipping off other dinosaurs, which was my first thought.  But then, I'm a non-specialist.

So a pretty cool discovery in China, elucidating the origins of modern birds and their ties to extinct, more conventionally dinosaur-like species.  Makes me kind of sorry the big toothy birds are gone.  That would add a whole new level of excitement to birdwatching, wouldn't it?

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In August of 1883, one of the largest volcanic eruptions in human history (literally) obliterated an island in the Sunda Strait between Java and Sumatra.

The island was Krakatoa (now known by its more correct spelling of "Krakatau").  The magnitude of the explosion is nearly incomprehensible.  It generated a sound estimated at 310 decibels, loud enough to be heard five thousand kilometers away (sailors forty kilometers away suffered ruptured eardrums).  Rafts of volcanic pumice, some of which contained human skeletons, washed up in East Africa after making their way across the entire Indian Ocean.  Thirty-six thousand people died, many of whom were not killed by the eruption itself but by the horrifying tsunamis that resulted, in some places measuring over forty meters above sea level.

Simon Winchester, a British journalist and author, wrote a book about the lead-up to that fateful day in summer of 1883.  It is as lucid and fascinating as his other books, which include A Crack at the Edge of the World (about the 1906 San Francisco earthquake), The Map that Changed the World (a brilliant look at the man who created the first accurate geological map of England), and The Surgeon of Crowthorne (the biographies of the two men who created the Oxford English Dictionary -- one of whom was in a prison for the criminally insane).

So if you're a fan of excellent historical and science writing, or (like me) fascinated with volcanoes, earthquakes, and plate tectonics, you definitely need to read Krakatoa: The Day the World Exploded.  It will give you a healthy respect for the powerful forces that create the topography of our planet -- some of which wield destructive power greater than anything we can imagine.

A fight over teeth

It may seem like a trivial thing to gripe about, but I am absolutely sick unto death of people taking some completely ordinary scientific discovery, and shrieking, "This will completely rewrite every textbook on the subject!", or worse, "This invalidates everything we thought we knew about X!"

I know a bit about the history of scientific inquiry.  I'm no expert, but I'm definitely Better Than The Average Bear.  And when it comes to real, honest-to-Galileo scientific revolutions, I can only think of a few:

• The Copernican idea of the planets (including the Earth) going around the Sun, further modified by Kepler, who found out they weren't moving in perfect circles
• Isaac Newton's theories of force, motion, and gravitation
• Charles Darwin's explanation of the mechanism of evolution
• The elucidation of electricity and magnetism by James Clerk Maxwell and others
• The discovery of the gene as the fundamental unit of heredity, followed by a century and a half of refinement of our understanding of how DNA produces traits
• The discovery of radioactivity, which directly led to our understanding of atomic structure and quantum mechanics -- a discovery, it must be said, that immediately followed the eminent physicist Lord Kelvin stating, "There is nothing new to be discovered in physics now.  All that remains is more and more precise measurement."
• The discovery of plate tectonics as a driver for geological processes, by Alfred Wegener, Harry Hess, J. Tuzo Wilson, and others

And that's about it.  Oh, there were other big developments.  The invention of the computer, for example, has changed our experience about as much as anything I can think of.  But it really wasn't an overturning of our understanding of how the world works; it was more a new and clever application of known physical laws to the problem of computation and information storage.

So what stands out about real scientific revolutions is how uncommon they are.  And given the precision of our tools, and the level of our inquiry in the past century, the chances of our having missed something fundamental is pretty slim.

Which is why I rolled my eyes and said a very bad word when I saw an article over at Inverse entitled, "9.7 Million-Year-Old Teeth Found In Germany Could Recast Human History."  The discovery, which is actually fairly cool, is that a team led by Herbert Lutz, director of the Natural History Museum of Mainz, Germany discovered some hominin teeth in a dig near the Rhine River.  It is an unusual find; most of the hominin fossils of that age have been confined to Africa.  But it certainly doesn't "rewrite human history."  The fact that there might have been a branch of hominins that made it to Europe ten-odd million years ago is interesting, but doesn't really overturn anything.  It just adds a branch to our family tree (and one that almost certainly isn't our director ancestor, anyhow).

One of the Eppelsheim teeth [image courtesy of the Mainz Natural History Museum]

Lutz himself didn't help matters any by his statement to the press.  "It’s something completely new, something previously unknown to science," Lutz said.  "It’s a complete mystery where this individual came from, and why nobody’s ever found a tooth like this somewhere before."

I can put this reaction down to a scientist being understandably excited about his own work.  But when the media hears the words "unknown to science" and "mystery," they picture scientists sitting around with befuddled looks on their faces, then standing up and throwing away all of the textbooks and journals on the subject in question.

Which is a far sight from the truth, as Michael Greshko of National Geographic states.  "Do these teeth, as many news outlets have proclaimed, 'rewrite human history?'" Greshko writes.  "In a word, no."

In fact, there's still a lot of argument amongst paleontologists over whether the teeth are actually from a hominin, as Lutz believes.  Bence Viola of the University of Toronto, a world-renowned expert on the structure of hominin and hominoid teeth, is doubtful.  "I think this is much ado about nothing," Viola said.  "The second tooth (the molar), which they say clearly comes from the same individual, is absolutely not a hominin, [and] I would say also not a hominoid."

Viola suspects that the teeth are from some kind of pliopithecoid, a branch of primates only distantly related to humans, and which are known to have lived in Europe and Asia between seven and seventeen million years ago.

Viola's colleague, paleoanthropologist David Begun, is even more dismissive.  "The 'canine' looks to me like a piece of a ruminant tooth," Begun said.  "It has a funny break that makes it look a bit like a canine, but it is definitely not a canine, nor is it [from] a primate."

So not only do the teeth not "rewrite human history," there isn't even agreement about what animal the teeth were from.  So if you were thinking we were going to add an eighth scientific revolution to the seven I mentioned above based on Lutz's discovery, I fear you are destined for disappointment.

And the problem only gets worse when you're talking about a field in which people have a vested interest to disbelieve.  I can't tell you the number of times I've seen headlines like, "Paleontologist Finds Bone in a Dig Site -- Evolutionists Baffled!" or "Blizzard On the Way -- Climate Change Supporters Fumble for Explanation."  Trust me on this: no one's baffled or fumbling, and they're not rewriting the textbooks.  What the scientists are doing is adding another bit to our understanding of the universe.

Because that's how science works.