Tuning in and tuning out

Mexican free-tailed bats (Tadarida brasiliensis) are remarkable animals.  They live in staggeringly huge colonies.  The largest known, in Bracken Cave in Comal County north of San Antonio, Texas, has twenty million bats.  I got to see a smaller (but still impressive) colony, in Carlsbad Caverns National Park, New Mexico, when I was a kid, and I'll never forget the sight of the thousands and thousands of bats streaming out of the cave mouth at dusk.

Free-tailed bats echolocate, which you probably already knew; they navigate in the dark by vocalizing and then listening for the echoes, creating a "sonic landscape" of their surroundings accurate enough to snag an insect out of the air in pitch darkness.  But this engenders two problems, which I honestly never though of until they were brought up by the professor of my Vertebrate Zoology course when I was in graduate school:

1. If these bats live in groups of millions of individuals, how do they tune in to the echoes of their own voices, distinguishing them from the cacophony of their friends and family all vocalizing at the same time?
2. In order to echolocate, they must have exquisitely sensitive hearing.  They're picking up the faint echoes of their own calls with an accuracy that allows them to detect the contours and motion (if any) of the object they're sensing.  To create an audible echo, they have to vocalize really loudly.  So how does the original vocalization not deafen those sensitive ears?

The answer to the first was discovered by some research at the University of Tübingen back in 2009.  Using recordings, scientists found that bats are sensitive not only to the echoes themselves, but can pick out from those echoes enough information about the sonic waveform that they can recognize their own voices.  Each bat's voice has a distinct, if not unique, sonic "fingerprint" -- much like human voices.

The answer to the second is, if anything, even more astonishing.  Just as humans do, bats have three tiny sound-conducting bones in their middle ear -- the malleus, incus, and stapes (commonly known as the hammer, anvil, and stirrup) -- that transmit sound from the eardrum into the cochlea (the organ of hearing).  Bats have a tiny muscle attached to the malleus, and when they open their mouths to vocalize, the muscle contracts, pulling the malleus away from the incus.  Result: dramatically decreased sound transmission.  But even more amazing, as soon as they stop vocalizing, the muscle relaxes -- fast enough to bring the malleus back in contact with the incus in time to pick up the echo.

Bats, it turns out, aren't the only animals to experience these sorts of problems.  The reason this whole topic comes up is because of some research that was published last week in The Journal of Neuroscience.  In a paper called "Signal Diversification is Associated with Corollary Discharge Evolution in Weakly Electric Fish," by Matasaburo Fukutomi and Bruce Carlson of Washington University, we learn about a group of fish called mormyrids (elephant fish) that have, in effect, the opposite problem from bats; they have to find a way to tune out their own communication so they can sense that of their neighbors.

Long-nosed elephant fish (Gnathonemus petersii)  [Image licensed under the Creative Commons spinola, Elefantenrüsselfisch, CC BY-SA 3.0]

Mormyrids communicate by electrical signals; the long "trunk" is actually an exquisitely-sensitive electrical sensor.  They not only use it to pick up electrical signals given off the nerves and muscles of the insect larva prey they feed on, they use it to pick up those sent by other members of their own species.  In effect, they talk using voltage.

Here, though, they have to be able to ignore the voltage shifts in the water around them given off by their own bodies.  It's as if you were in a conversation with a friend, and instead of doing what most civilized friends do -- taking turns talking -- you both babble continuously, and your brain simply stops paying attention to your own voice.

They do this using a corollary discharge, an inhibitory signal that blocks the higher parts of the brain from responding to the signal.  The researchers found that corollary discharges only occurred in response to voltage changes from the individual itself, and not to those from other individuals.

In other words, just like the bats, mormyrid fish can recognize their own communications.  "Despite the complexity of sensory and motor systems working together to deal with the problem of separating self-generated from external signals, it seems like the principle is very simple," said study co-author Bruce Carlson, in an interview with Science Daily.  "The systems talk to each other.  Somehow, they adjust to even widespread, dramatic changes in signals over short periods of evolutionary time."

So there you have it.  Another natural phenomenon to be impressed by.  It reminds me of the wonderful TED talk by David Eagleman called, "Can We Develop New Senses for Humans?" that talks about an animal's umwelt -- in essence, how it perceives the world.  What must the world seem like to a fish that gathers most of its information from electrical signals?

Staggers the imagination, doesn't it?

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Fan of true crime stories?  This week's Skeptophilia book recommendation of the week is for you.

In The Poisoner's Handbook:Murder and the Birth of Forensic Medicine in Jazz Age New York, by Deborah Blum, you'll find out about how forensic science got off the ground -- through the efforts of two scientists, Charles Norris and Alexander Gettler, who took on the corruption-ridden law enforcement offices of Tammany Hall in order to stop people from literally getting away with murder.

In a book that reads more like a crime thriller than it does history, Blum takes us along with Norris and Gettler as they turned crime detection into a true science, resulting in hundreds of people being brought to justice for what would otherwise have been unsolved murders.  In Blum's hands, it's a fast, brilliant read -- if you're a fan of CSI, Forensics Files, and Bones, get a copy of The Poisoner's Handbook, you won't be able to put it down.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Wings over North Carolina

Rounding out Paleontology Week is a story courtesy of my friend and long-time loyal reader of Skeptophilia, the brilliant novelist Tyler Tork (whose new book The Deep End is a must-read for anyone who likes speculative fiction and magical realism).  And, I might add, it is completely on-brand for 2020.

So today we have: pterodactyl sightings are on the increase in the United States.

Pteranodon by Heinrich Harder (1916)  {Image is in the Public Domain]

Myself, I would have thought that one pterodactyl sighting would be an increase given that the number of currently-living pterodactyls is zero, but apparently I'm incorrect.  Evidently North Carolina is a hotspot of pterodactyl activity, where people are seeing big flying things with crests and a diamond-shaped rudder on the tail.  This sounds to me like my favorite pterodactyloid, Rhamphorhynchus:

[Image is in the Public Domain]

Now, I hasten to add that I don't really believe there are pterodactyls flying around Charlotte.  To me, there's the same problem with this as with all the Bigfoot claims; lots of anecdotal stories of sightings, and not a single unequivocal piece of hard evidence.  You'd think if these things were still around, someone would have run across a body or a skull or something.  Or even a fossil of one that isn't older than 66 million years.

But that doesn't stop the true believers.  Over at the sight LivePterosaurs.com (of course there's a website called "LivePterosaurs.com") you can read dozens of eyewitness accounts.  And much to my surprise, my home state of New York is not far behind North Carolina, according to this map:

So I think I better keep my eyes open.  Although even with my fairly lousy eyesight, it's hard to imagine how I could miss something that (according to one witness) "had an enormous pointed beak, and a pointed top of its head...  The wingspan was probably about 5-6 feet wide with bony wing structure ending in points (almost like sails) and what looked like small claws on the middle of wing."

Anyhow, after reading this article I made the mistake of looking at the "comments" section.  (This is, in fact, always a mistake.)  The comments seemed to be half "of course pterodactyls are still alive, I've seen one" and half "whatever you've been smoking, can I have some?"  But my favorite comment was from the woman who wrote (spelling and grammar are as written): "Wit all the ice melting.  Who knows what was frozen.  Or.  Wilderness caves where anything could hide."

So here we have yet another downside of global climate change; thawing out all the pterodactyls who have been encased in ice in the frozen wasteland of North Carolina for 66 million years.

In any case, if you had "pterodactyls" on your 2020 Apocalypse Bingo Card, you can check that box off.  And frankly, I'd take pterodactyls over murder hornets.  Have you ever seen a photograph of one of those things?  They are huge, and have a stinger like a fucking harpoon.  So I say: bring on the pterodactyls.

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This week's Skeptophilia book recommendation of the week is by the brilliant Dutch animal behaviorist Frans de Waal, whose work with capuchin monkeys and chimps has elucidated not only their behavior, but the origins of a lot of our own.  (For a taste of his work, watch the brilliant TED talk he did called "Moral Behavior in Animals.")

In his book Mama's Last Hug: Animal Emotions and What They Tell Us About Ourselves, de Waal looks at this topic in more detail, telling riveting stories about the emotions animals experience, and showing that their inner world is more like ours than we usually realize.  Our feelings of love, hate, jealousy, empathy, disgust, fear, and joy are not unique to humans, but have their roots in our distant ancestry -- and are shared by many, if not most, mammalian species.

If you're interested in animal behavior, Mama's Last Hug is a must-read.  In it, you'll find out that non-human animals have a rich emotional life, and one that resembles our own to a startling degree.  In looking at other animals, we are holding up a mirror to ourselves.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

The English dinosaurs

Continuing with the paleontological bent we've been on all week, today we have: bones of a previously-unknown tyrannosaur on a beach in England.

As unlikely as it sounds, beaches in southern England are great places to find dinosaur bones.  One of the founders of the science of paleontology, Mary Anning, did most of her work in the Lyme Regis region of the Dorsetshire coast during the first half of the nineteenth century, and her discovery of complete skeletons of Jurassic-era ichthyosaurs and plesiosaurs on walks with her faithful dog has become the stuff of legends.  (Sadly, her dog was killed in a landslide when a cliffside collapsed -- Anning missed sharing his fate because she was only a couple of feet ahead of him.)

The new find comes from Cretaceous sedimentary rocks on the coast of the Isle of Wight, where paleontologists from the University of Southampton have identified some fossilized bones as belonging to a new species that has been christened Vectaerovenator inopinatus (the name translates roughly to "unexpected air-filled hunter").  It got its name from the presence of air sacs in and around the bones.  This adaptation is also found in modern birds, re-emphasizing the relationship between predatory theropods and chickadees.

Vectaerovenator was a big guy -- an estimated four meters long -- but was astonishingly light-built.  "We were struck by just how hollow this animal was - it's riddled with air spaces," said Christopher Barker, who was lead author of the study.  "Parts of its skeleton must have been rather delicate.  The record of theropod dinosaurs from the 'mid' Cretaceous Period in Europe isn't that great, so it's been really exciting to be able to increase our understanding of the diversity of dinosaur species from this time...  You don't usually find dinosaurs in the deposits at Shanklin as they were laid down in a marine habitat.  You're much more likely to find fossil oysters or driftwood, so this is a rare find indeed."

The fossils were found in marine sedimentary rocks, and surmise is that the dinosaur they belonged to fell into a river (whether before or after it died is, of course, impossible to tell) and its body washed out into the shallow sea, where it was covered up and preserved.

Artist Trudie Wilson's impression of the final moments of the Shanklin Ventaerovenator inopinatus  [Image courtesy of the University of Southampton]

The bones were found by three amateur fossil-hunters.  Robin Ward of Stratford-upon-Avon, was walking on the beach with his family and found the first ones.  "The joy of finding the bones we discovered was absolutely fantastic," Ward said.  "I thought they were special and so took them along when we visited Dinosaur Isle Museum.  They immediately knew these were something rare and asked if we could donate them to the museum to be fully researched."

"It looked different from marine reptile vertebrae I have come across in the past," said James Lockyer, of Spalding, Lincolnshire, who found additional pieces of the skeleton.  "I was searching a spot at Shanklin and had been told and read that I wouldn't find much there.  However, I always make sure I search the areas others do not, and on this occasion it paid off."

Paul Farrell, an Isle of Wight native, contributed further pieces to the discovery.  "I was walking along the beach, kicking stones and came across what looked like a bone from a dinosaur," Farrell said.  "I was really shocked to find out it could be a new species."

All three agreed to donate their finds to the Dinosaur Isle Museum at Sandown.

What this highlights to me is the degree to which interested amateurs can contribute to science.  In fact, Mary Anning herself had no training in paleontology, or in fact, in any kind of science; to call opportunities for women in science in the early nineteenth century "limited" is a vast understatement.  Anning's descriptions of her extraordinary discoveries were turned down for publication by the Magazine of Natural History, and she was denied entry to the Geological Society of London purely because of her gender.

So it's a double-edged sword, isn't it?  Talented amateurs can make incredible contributions, but only if the often hidebound powers-that-be will allow them.  Sometimes it's an uphill struggle just to gain a small amount of credibility, and in Anning's case, even that never happened.  Shortly before her death from breast cancer at the age of 47, she wrote, "The world has used me so unkindly, I fear it has made me suspicious of everyone."

Fortunately, that isn't the case here, and the amateurs and the scientists are happily collaborating.  With luck and persistence, we will continue to learn about the prehistoric landscape of England as it was 115 million years ago, when dinosaurs like Ventaerovenator were prowling the shores.

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This week's Skeptophilia book recommendation of the week is by the brilliant Dutch animal behaviorist Frans de Waal, whose work with capuchin monkeys and chimps has elucidated not only their behavior, but the origins of a lot of our own.  (For a taste of his work, watch the brilliant TED talk he did called "Moral Behavior in Animals.")

In his book Mama's Last Hug: Animal Emotions and What They Tell Us About Ourselves, de Waal looks at this topic in more detail, telling riveting stories about the emotions animals experience, and showing that their inner world is more like ours than we usually realize.  Our feelings of love, hate, jealousy, empathy, disgust, fear, and joy are not unique to humans, but have their roots in our distant ancestry -- and are shared by many, if not most, mammalian species.

If you're interested in animal behavior, Mama's Last Hug is a must-read.  In it, you'll find out that non-human animals have a rich emotional life, and one that resembles our own to a startling degree.  In looking at other animals, we are holding up a mirror to ourselves.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Taking flight

One of the many things I find fascinating about the evolutionary model is how different lineages can happen on the same "solution" to the problems of surviving and reproducing, leading to similarities cropping up that don't result from common ancestry.  This is a phenomenon called convergent evolution, and explains why the North American flying squirrel and Australian sugar glider look a lot alike, even though they are only distantly related.  (The flying squirrel is a rodent, and the sugar glider a marsupial more closely related to kangaroos.)

I put the word "solution" in quotes and use it with caution, because this makes it sound like evolution is forward-looking, which it is not.  As Richard Dawkins explains brilliantly in his book The Blind Watchmaker, to trigger evolution, all you have to have is an imperfect replicator (in this case, DNA) and a selecting agent.  To phrase it more like Darwin would have put it: variation coupled with differences in survival rate.

I recall how surprised I was to learn that the eye had actually evolved multiple times.  Starting with light-sensitive spots, such as you still find today in many microorganisms, variations on different lineages came up with a variety of different "solutions" -- the pinhole-camera eye of a chambered nautilus, the cup-shaped eye of a flatworm, the compound eye of a fly, and our own eye with a transparent lens like that of a refracting telescope.  All these adaptations work just fine for the animal that has them.  (Eye formation in a number of species is controlled by the paired-box 6 [PAX6] gene, without which eyes won't form at all.  It's such a critical gene that it is conserved across thousands of species -- in fact, your PAX6 gene and a mouse's are identical, base-pair-for-base-pair.)

The reason this subject comes up is because of some research published in the journal Current Biology last week that showed another trait -- flight -- not only evolved separately in groups like insects and birds, but even in the dinosaurian ancestors of today's birds, it evolved more than once.

A team led by paleontologist Rui Pei of the Chinese Academy of Sciences analyzed bone and feather structure of various dinosaur groups to see if they flew, glided, or were using their feathers for a different purpose (such as keeping warm).  To their surprise, it was found that multiple lineages were capable of flying or nearly so.  The authors write:

We [used] an ancestral state reconstruction analysis calculating maximum and minimum estimates of two proxies of powered flight potential—wing loading and specific lift.  These results confirm powered flight potential in early birds but its rarity among the ancestors of the closest avialan relatives (select unenlagiine and microraptorine dromaeosaurids).  For the first time, we find a broad range of these ancestors neared the wing loading and specific lift thresholds indicative of powered flight potential.  This suggests there was greater experimentation with wing-assisted locomotion before theropod flight evolved than previously appreciated.  This study adds invaluable support for multiple origins of powered flight potential in theropods (≥3 times), which we now know was from ancestors already nearing associated thresholds, and provides a framework for its further study.

Here are their results, in graphical form:

As you can see, actual birds -- labeled "Later-diverging avialans" near the bottom of the tree -- were far from the only ones to have flight capability.  Rahonavis, Microraptor, and several of the anchiornithines were probably fliers, and only the last mentioned is on the same clade as today's birds.

Flying is pretty useful, so it's no wonder that when feathers evolved from scales -- probably, as I mentioned earlier, in the context of warmth and insulation -- it was only a small step remaining toward lengthening those feathers to the point that their owners could catch a breeze and glide.  After that, the same kind of refinement took over that happened with the eye, and eventually, you have true flight.

So that's yet another cool bit of research about prehistory.  Wouldn't you like to know what those prehistoric fliers looked like?  I'd love to see them.  From a distance, because a lot of them were predators.  For example, Microraptor is Greek for "tiny hunter," and were a little like miniature velociraptors with wings.

If you wanted an image to haunt your dreams.

***********************************

This week's Skeptophilia book recommendation of the week is by the brilliant Dutch animal behaviorist Frans de Waal, whose work with capuchin monkeys and chimps has elucidated not only their behavior, but the origins of a lot of our own.  (For a taste of his work, watch the brilliant TED talk he did called "Moral Behavior in Animals.")

In his book Mama's Last Hug: Animal Emotions and What They Tell Us About Ourselves, de Waal looks at this topic in more detail, telling riveting stories about the emotions animals experience, and showing that their inner world is more like ours than we usually realize.  Our feelings of love, hate, jealousy, empathy, disgust, fear, and joy are not unique to humans, but have their roots in our distant ancestry -- and are shared by many, if not most, mammalian species.

If you're interested in animal behavior, Mama's Last Hug is a must-read.  In it, you'll find out that non-human animals have a rich emotional life, and one that resembles our own to a startling degree.  In looking at other animals, we are holding up a mirror to ourselves.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

After 'while, crocodile

Because I have an endless fascination for things that are big and powerful and can kill you, today's topic is: Deinosuchus.

If you know a little Greek, the name itself should put you on notice.  It comes from the words δεινός (terror) and σοῦχος (crocodile).  Because crocodiles aren't terrifying enough on their own, apparently.  The largest extant crocodilian is the Australian saltwater crocodile, which can get to be about six meters in length and can weigh twelve hundred kilograms.  It regularly attacks humans, often stupid ones who don't know enough to stay away from the shallow water habitats it prefers, and as the Wikipedia article puts it, "As a result of its power, intimidating size and speed, survival of a direct predatory attack is unlikely if the crocodile is able to make direct contact."

Deinosuchus was just shy of twice as long.  Considering that the usual rule that the mass of an animal varies as the cube of its length, this would put the biggest ones at eight times heavier than a saltie -- something on the order of nine thousand kilograms.

That's equivalent to the mass of a school bus.  Just for reference.

If that's not bad enough, it had teeth up to a foot long.  Lots of them.  The largest species, Deinosuchus riograndensis, which lived (unsurprisingly) in what is now the western United States and northern Mexico, apparently fed on dinosaurs.

A reconstructed Deinosuchus hatcheri skeleton in the Natural History Museum of Utah.  [Image is in the Public Domain]

According to research published last week in The Journal of Vertebrate Paleontology -- which is why this whole horrifying topic comes up -- a combination of new fossil finds and re-analysis of old fossils, Deinosuchus was probably an ambush predator, like its much smaller modern Australian cousin.  It could, paleontologists believe, have taken down just about any of the dinosaurs alive at the time, up to the biggest ones.

"Deinosuchus was a giant that must have terrorized dinosaurs that came to the water's edge to drink," Adam Cossette, of the New York Institute of Technology College of Osteopathic Medicine at Arkansas State University.  "Until now, the complete animal was unknown.  These new specimens we've examined reveal a bizarre, monstrous predator with teeth the size of bananas."

During the time it was around -- the late Cretaceous Period, between 75 and 82 million years ago -- it lived in similar habitats to the Australian saltwater crocodile.  At that time, North America was split in two by a shallow sea that extended from the Arctic Ocean to what is now the Gulf of Mexico, and which covered most of what is now the Midwest and Southeast.  The Western Interior Seaway, as it was called, separated the small continent of Laramidia (now the Southwest, California, and the Pacific Northwest) from Appalachia (the mid-Atlantic, Northeast, and eastern Canada).  (If you're curious, the surreal, brightly-colored rock formations in what is now Bryce Canyon National Park, in Utah, were deposited at this time.  Hard to imagine that what is now high desert was once a shallow tropical sea, but it was.)

So Deinosuchus would have lived on both sides of that narrow sea, laying in wait for any prey to come along.  Also found in these same rocks are fossils of Pteranodon, the familiar crested pterodactyloid, along with hadrosaurs (duck-billed dinosaurs) and monstrous turtles like Archelon, which is estimated at five meters in length and weighing about two thousand kilograms.

Hard to picture that tableau as having occurred in what is now Kansas.

One of the weirder things about Deinosuchus is that it didn't make it to the Cretaceous Extinction.  It died out about 75 million years ago, missing getting fried by the Chicxulub Meteorite strike by a good nine million years.  What wiped it out is unknown, but there's a general pattern that if the environment changes, apex predators get hit the hardest -- they're usually slow-reproducing, and their survival depends on the entire biotic web being intact.  (Consider that most of the modern large mammalian predators are on the Endangered Species List.)

There comes a point where superlatives fail me, and I think I've hit it.  I'll leave the rest to your imagination.  Suffice it to say that while it was around, it was the unchallenged ruler of the Western Interior Seaway.  And honestly, cool as it undoubtedly was, I'm just as glad those aren't lurking around any more.  Australian saltwater crocodiles are terrifying enough.

***********************************

This week's Skeptophilia book recommendation of the week is by the brilliant Dutch animal behaviorist Frans de Waal, whose work with capuchin monkeys and chimps has elucidated not only their behavior, but the origins of a lot of our own.  (For a taste of his work, watch the brilliant TED talk he did called "Moral Behavior in Animals.")

In his book Mama's Last Hug: Animal Emotions and What They Tell Us About Ourselves, de Waal looks at this topic in more detail, telling riveting stories about the emotions animals experience, and showing that their inner world is more like ours than we usually realize.  Our feelings of love, hate, jealousy, empathy, disgust, fear, and joy are not unique to humans, but have their roots in our distant ancestry -- and are shared by many, if not most, mammalian species.

If you're interested in animal behavior, Mama's Last Hug is a must-read.  In it, you'll find out that non-human animals have a rich emotional life, and one that resembles our own to a startling degree.  In looking at other animals, we are holding up a mirror to ourselves.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

Fishy business

My evolutionary biology professor told our class, many years ago, "The only reason we came up with the word species is because humans have no near relatives."

It's a comment that has stuck with me.  We perceive species as being these little cubbyholes with impenetrable sides, and once you've filed something there, it stays put.  Of course a polar bear and a grizzly bear are different species.  How could they be otherwise?

But when you start pushing at the definition a little, you find that it gives way almost immediately.  Ask some non-scientist how they know polar bears and grizzly bears are different species, and you'll likely get an answer like, "Because they look completely different."  And, to be fair, that's more or less how the father of taxonomy, Carl Linnaeus, did it.

Problems creep in almost immediately, though.  The "of course different species" polar and grizzly bears look far more alike than do, say, a chihuahua and a St. Bernard.  (Imagine trying to convince an alien biologist that those two are members of the same species.)  So very quickly, scientists were forced into refining the definition so as to capture the separateness of two different species in such a way that the term could be applied consistently.

What they ultimately landed on was the canonical definition used in just about every biology textbook in the world: "Members of the same species are capable of potentially interbreeding and producing viable and fertile offspring."  (The "fertile" part had to be added because of the famous example of a horse and a donkey being able to produce a viable hybrid -- but that hybrid, the mule, is almost always infertile.)

The problem was, even that wasn't enough to clarify things. Polar bears and grizzly bears, for example, can and do hybridize in the wild, and the offspring (the rather unfortunately-named "pizzly bear") are almost always fertile.  This isn't an aberration.  These kinds of situations are common in the wild.  In fact, in my part of the world, there are two birds that look dramatically different -- the blue-winged warbler and the golden-winged warbler -- but they will happily crossbreed.  When the hybrids were first observed by scientists, they were different enough from both parents that it was thought they were a third separate species, which was called Brewster's warbler.  It was only after long observation that biologists figured out what was going on -- especially given that "Brewster's warblers" are potentially interfertile with either parental species.

In fact, the more you press the definition, the more it falls apart, the more exceptions you find.  Today's taxonomists are usually wary about labeling something a "species" -- or when they do, they're aware that it's potentially an artificial distinction that has no particular technical relevance.  They are much more comfortable talking about genetic overlap and most recent common ancestry, which at least are measurable.

The reason all this comes up is because of a startling discovery brought to my attention by a friend and long-time loyal reader of Skeptophilia.  Researchers in Hungary have produced a hybrid between an American paddlefish and a Russian sturgeon -- two species no one could confuse with each other -- and they appear to be fertile, and normal in every other way.

The more you look at these "sturddlefish," the more shocking they get.  Sturgeon and paddlefish are not only separate species, they're in separate families -- two layers of classification above species.  "I’m still confused," said Prosanta Chakrabarty, ichthyologist at Louisiana State University.  "My jaw is still on the floor.  It’s like if they had a cow and a giraffe make a baby."

He quickly amended that statement -- giraffes and cows have a recent common ancestor only a few million years ago, whereas paddlefish and sturgeons have been separate lineages for 184 million years.  To get anything comparable, Chakrabarty said, you'd have to have something like a human coming out of a platypus egg.

The scientists believe that the reason this happened is because of the relatively slow rate of evolution of both lineages (especially the sturgeons).  Sturgeons now look pretty similar to sturgeons two hundred million years ago, while almost all of the mammalian biodiversity you see around you -- divergence between, say, a raccoon and a squirrel -- happened since the Cretaceous Extinction, 66 million years ago.  But even so, it's pretty remarkable.  To my eye, paddlefish and sturgeon look way more different than lots of pairs of species that can't interbreed, so once again, we're confronted with the fact that the concept of species isn't what we thought it was -- if it has any biological relevance at all.

Atlantic Sturgeon (Acipenser oxyrhynchus)

American Paddlefish (Polyodon spathula)  [Both this and the above image are in the Public Domain]

This brings us back to the unsettling (but exciting) fact that whenever we think we have everything figured out, nature reaches out and astonishes us.  It's why I'll never tire of biology -- to paraphrase Socrates, the more we know, the more we realize how little we know.

But one thing I know for sure is that the biologists really need to come up with better names than "sturddlefish" and "pizzly bear."

***********************************

This week's Skeptophilia book recommendation of the week is by the brilliant Dutch animal behaviorist Frans de Waal, whose work with capuchin monkeys and chimps has elucidated not only their behavior, but the origins of a lot of our own.  (For a taste of his work, watch the brilliant TED talk he did called "Moral Behavior in Animals.")

In his book Mama's Last Hug: Animal Emotions and What They Tell Us About Ourselves, de Waal looks at this topic in more detail, telling riveting stories about the emotions animals experience, and showing that their inner world is more like ours than we usually realize.  Our feelings of love, hate, jealousy, empathy, disgust, fear, and joy are not unique to humans, but have their roots in our distant ancestry -- and are shared by many, if not most, mammalian species.

If you're interested in animal behavior, Mama's Last Hug is a must-read.  In it, you'll find out that non-human animals have a rich emotional life, and one that resembles our own to a startling degree.  In looking at other animals, we are holding up a mirror to ourselves.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]

A portrait in black-and-white

My mother was born Marguerite Thérèse Ayo in the little town of Schriever, Louisiana, on August 10, 1920, exactly a hundred years ago.  She was the middle of three children.  Her father was an insurance salesman, a kind, soft-spoken man who was absent from the home a good bit of the time.  Her mother -- typical of the time -- was a stay-at-home mom, and from what I've heard was an exacting, demanding woman who expected her children to be perfect.

Left to right: my aunt Florence, my grandmother (Flora (Meyer-Lévy) Ayo), my uncle Sidney, and my mom.  

The photograph above speaks volumes.  According to my mother, when the film was developed, Florence was the only one who met with approval.  Sidney's belt end had flopped down and my mom's stockings were wrinkled at the knees, something they heard about every time my grandmother looked at this photograph.  My mom had a bad case of middle-child syndrome -- her older sister was the picture of etiquette and academic success, and her younger brother got away with murder because he was the youngest and the only boy.  My mom never felt like she could measure up.

My mom at about 12

Historian Arnold Toynbee famously said "Life is just one damned thing after another," and that was certainly true in my mom's case.  When I think of what happened to her over her more than eight decades of life, what strikes me is that she got knocked down again and again by circumstances outside her control.  As I mentioned, she never got much approval from either parent.  When she was 17, her mother had a stroke at the young age of 44, and it changed her already difficult personality for the worse -- now she was largely housebound, had difficulty walking and talking, and found fault with everything and everyone.

My mom, age around 18

My mom escaped by marrying my dad, then a private in the Marine Corps.  It was the first years of World War II and my dad ended up stationed in Hawaii (in fact, they were in Honolulu and heard the bombs striking Pearl Harbor).  In 1945 my sister Margaret Mary was born -- but she was premature and had Rh-incompatibility syndrome, then a dire and life-threatening emergency, and only lived nine days.

My grandmother had a second stroke and died shortly after the war ended.  My parents had neither the resources nor the opportunity to return to Louisiana for the funeral, and in traditional Cajun culture, not going to a close relative's funeral is about as disrespectful as you can get.  Everyone said they understood, but my mom never forgave herself.

My mom shortly after the end of the war

Over the next decade, my dad was bounced around from military base to military base.  For three years, in the 1950s, he lived on a base in Japan.  Left alone at home, my mom did the best she could, and that was when she found her true passion -- art.  She learned painting, sculpture, and (especially) ceramics, and created some amazing works in porcelain.  Here's one of her bone china dolls:

The lace itself is made of bone china.  Don't ask me how she did it.

My parents wanted children, and after the loss of my sister, they tried.  No luck.  Doctors' visits showed nothing physically wrong with either one, but no success.  Fifteen years after my sister's death, my mom was forty years old and had resigned herself to being childless.  She was preparing to throw herself into becoming a full-time studio artist...

... when I came along.

Me and my mom, June of 1961

I won't say I wasn't wanted; but when my parents said I was their "mistake," it was only half kidding.  I busted up my mother's plans of being a full-time artist without even knowing I'd done it.  Then in late 1961, shortly after this photo was taken, my dad got transferred -- to Reykjavík, Iceland.  Back then enlisted men couldn't bring their families along to most overseas assignments, so for two years my mom and I only saw my dad when he was on furlough.  She and I moved in with her father, who had by then remarried.

Imagine it.  You're a forty-year-old with your only child, and you have to move back to your father's house and live with him and with a stepmother whom you frankly detest.  Once again, fate had given her a good gut punch.

This is where it gets complicated, because my mom honestly tried to jump into her new role as mother as well as she could.  But our relationship was fractious pretty much from the beginning.  I was about as opposite to her picture of "the perfect son" as it's possible to be.  She wanted a tough, independent, all-American boy, who was a solid-B student and played baseball and went fishing and hunting on the weekend.  She got me -- a bookish, nearsighted, sensitive dreamer who wanted to spend his time reading and making up stories, who hated team sports with a passion and whose idea of athletics was going on a solo five-mile run.  Despite my being reasonably smart, she couldn't even brag about my academic prowess -- my grades yo-yoed all over the place, depending on whether I liked the teacher and whether during that grading period I'd focused on learning about the Franco-Prussian War instead of inventing characters to send on adventures in time and space.

Plus, there was the problem that she and I never honestly understood each other, not on any kind of deep level.  She was a devout Roman Catholic; I was a doubter pretty much the moment I was old enough to consider the question.  She had an innate respect for authority; my general attitude toward authority was "either earn my respect, or go to hell."  She was a staunch conservative; I was born leaning to the left.  She liked everything in black-and-white -- people were good or bad, a thing was true or not, an action was right or it was wrong.  Me, I saw (and still see) pretty much everything in shades of gray.

It was almost like she and I didn't speak the same language.

My dad was stationed for a time in Charleston, West Virginia, and we lived in the town of St. Albans, where my mom met a neighbor named Garnett Mudd, the woman my mom called "the only real friend I ever had."  They were kindred spirits, especially in their love of gardening, and I remember Garnett as being a wise and gentle person with wide-ranging knowledge and a brilliant sense of humor.  Then -- my parents got transferred again, and they had to leave West Virginia.  And as if this wasn't bad enough, six months after they moved away, Garnett was walking home from the school where she taught and died of a massive heart attack at the age of 57. 

And once again, my mom's world closed in on her a little more.

My dad retired in 1967 and we moved back to his home town of Lafayette, Louisiana.  For a year I lived with my paternal grandmother -- ostensibly because they were in the process of building a house and the little room they rented didn't have space for me, but I think honestly it was mostly because my mom was having trouble dealing with me.  This led to another fractious relationship -- between my mom and her mother-in-law.  In retrospect, I have to admit my paternal grandmother wasn't an easy person.  I idolized her, but she and my mom never got along -- as far as I've heard, right from the start.  The fact that I preferred being with my grandmother has to have rankled.  Whatever the cause, pretty much every time they were together, there was an argument, and no matter how petty the cause, neither one would ever give the other an inch.

It was during this time that my mom developed rheumatoid arthritis, a horrible disease that gradually robbed her of her mobility, and worse, of her ability to use her hands.  Her art became less a joy than a painful frustration.  I remember her during my teenage years as being in perpetual pain.  By then, we were at continual loggerheads over just about everything.  So on top of the usual teenage angst, stubbornness, and rebellion, there was a good dose of spite in my behavior -- of my doing things deliberately to set her off.

You'd think she'd have looked forward to my moving out, but when I was looking at colleges, my parents were adamant that I attend the University of Louisiana, in my home town, live at home rather than in the dorms, and commute.  Considering my attitude, to this day I don't know why they didn't hand me my suitcase and say "good riddance" to me.  I also don't know why I didn't push harder to move away.  Having space from each other would have done all of us a world of good, I think.  But she pressed, and I caved, and in what I think is one of the worst personal mistakes I've ever made, I stayed at home while going to college.  During a time when most people are dating, partying, and forming friendships, I had a nearly zero social life.  I had some friends I saw at school; but after class was over, I went home and stayed home.  And still my mom and I frayed each other on a daily basis.

I finally moved away after graduation in 1982, because I'd met the woman who would become my first wife.  It is not an exaggeration to say that my mom and Anne loathed each other.  My mom, who prided herself on following the rules of etiquette, could barely say a polite word to Anne about anything.  To be fair, Anne was far from blameless herself; my first marriage was, in a word, a mistake, which is another topic in and of itself.  But by that time I was desperate to get out, and Anne was my ticket -- to her home town of Seattle, Washington.

Visits home were few, tense, and as short as we could make them for propriety's sake.  From the outside, everything probably looked hunky-dory -- my mom told friends and neighbors about her pride when I got my teaching license and landed my first full-time teaching position, then when my two sons were born.  But the fact remained that we just didn't understand each other, and conversations were like walking in a minefield.  By this time we were usually able to avoid arguments, largely because we rarely talked about anything more meaningful than how the boys were doing and how my job was going.

Ultimately Anne and I divorced, and a few years later, I remarried to Carol, two of the only things I've ever done that met with my mom's 100% unequivocal approval.  (I still recall that when Carol and I were dating, in 2001, she had a business trip that would take her through Lafayette, and she bravely arranged to visit my parents.  I was a nervous wreck until the visit was over -- but to Carol's credit and my complete shock, it was a resounding success.)  My dad died of a stroke on July 4, 2004, and my mom followed eight months later, on February 19, 2005.

My mom with her two grandsons in the Blue Dog Café, Lafayette, Louisiana, in December 2004, three months before her death at age 84

Thinking about my mother on what would be her hundredth birthday, I'm experiencing mixed emotions.  I feel sorry for all the adversity she faced during her life -- it seemed like fate dealt her blow after blow, and as soon as she stood up from one knockdown, she was hit again from a different direction.  I have a lot of regret for not working harder to get along with her, for not realizing at the time how much of our rough relationship was because of the emotional pain she'd endured.  I don't know that even in the best of circumstances, we'd ever have been close -- it's hard to imagine two people so different ever really understanding each other -- but I know I could have done much better, and if I could sit down now and talk with her about it, I think she'd have to admit she could have, too.

Still, we were both doing the best we knew how at the time.  Suffice it to say that in our own fashion, and to the extent we could, we loved each other.

Happy birthday, Mom.  As hard as it was on both of us sometimes, I wish I could say it to you in person.

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This week's Skeptophilia book recommendation of the week is by the brilliant Dutch animal behaviorist Frans de Waal, whose work with capuchin monkeys and chimps has elucidated not only their behavior, but the origins of a lot of our own.  (For a taste of his work, watch the brilliant TED talk he did called "Moral Behavior in Animals.")

In his book Mama's Last Hug: Animal Emotions and What They Tell Us About Ourselves, de Waal looks at this topic in more detail, telling riveting stories about the emotions animals experience, and showing that their inner world is more like ours than we usually realize.  Our feelings of love, hate, jealousy, empathy, disgust, fear, and joy are not unique to humans, but have their roots in our distant ancestry -- and are shared by many, if not most, mammalian species.

If you're interested in animal behavior, Mama's Last Hug is a must-read.  In it, you'll find out that non-human animals have a rich emotional life, and one that resembles our own to a startling degree.  In looking at other animals, we are holding up a mirror to ourselves.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!]