Death... with big, nasty, pointy teeth

Today I'm going to write about a piece of research that isn't controversial, or deeply thought-provoking, or politically relevant, but because it's just plain awesome.

It's from the realm of paleontology, and is about a gigantic carnivore, which is part of its appeal.  Have you noticed how the little-kid fascination with dinosaurs usually revolves around carnivorous ones like Velociraptor and Tyrannosaurus rex?  They're seldom as impressed by herbivores like Pachycephalosaurus, which also has the disadvantage of meaning "thick-headed lizard," so it's kind of unimpressive right from the get-go.  Velociraptor, though?  "Swift hunter?"  Now that's cool.  You can bet that those wicked pack-hunters would never have put up with being given a humiliating name.  I bet if the paleontologists had decided to name them Brocchodentidorkosaurus ("buck-toothed dorky lizard"), the raptors would have eaten them for lunch, and that's even considering the fact that they've been extinct for seventy million years.

The dinosaurs, not the paleontologists.

But I digress.

The subject of today's post is a mammal called Simbakubwa kutokaafrika, which means "humongous lion from Africa" in Swahili (speaking of impressive names), even though it wasn't a lion at all.  It was a hyaenodont, a predatory group of mammals that are in Order Creodonta, a group only distantly related to modern Order Carnivora (i.e., cats, dogs, bears, weasels, seals, and a few other families).  The creodonts are an interesting group, at least to evolutionary biologists, because there's still a major argument going on regarding how to assemble their family tree.  Some paleontologists believe they're monophyletic -- all descended from a single common ancestor -- while others say they're polyphyletic, with different groups of creodonts coming from different ancestors that were further apart on the mammalian clade.

Whichever it is, they've now been shown through detailed skeletal analysis to have a closer connection to the bizarre pangolins than they do to today's carnivores -- yet another example of how common sense can lead to the wrong answer.

Reconstruction of a hyaenodont by Heinrich Harder [Image is in the Public Domain]

In any case, Simbakubwa was discovered recently by Duke University paleontologist Matt Borths, who was going through some fossils in the back rooms of the Nairobi National Museum when he found something that made him sit up and take notice:

The remains of a carnivorous mammal that was an estimated 1.2 meters tall at the shoulder, 2.4 meters from tip to tail, weighed an estimated five hundred kilograms, had canine teeth the size of bananas, and had three sets of incisors, two of which were big, nasty, and pointy.

That, my friends, is one serious carnivore.  That's a carnivore that could have turned your average African lion into an African lion meatloaf.

Simbakubwa is estimated to have lived around 23 million years ago, placing it in the early Miocene, but the creodonts as a group were apex carnivores for a lot longer than that.  They originated in the Paleocene (the epoch that began with the K-T extinction, 66 million years ago), and made it to the mid-Miocene (14 million years ago).  Modern(ish) true carnivores (i.e. Order Carnivora) first showed up 42 million years ago (the mid-Eocene epoch), and only reached Africa around 22 million years ago -- right around the time Simbakubwa was lumbering around the place.  So no wonder the true carnivores only began to diversify in Africa after the hyaenodonts were safely out of the way, eight million years later.

All of this highlights two things -- first, what amazing discoveries might be lurking on dusty museum shelves, forgotten and unstudied; and second, that we honestly don't know very much about what critters were out there in prehistoric times.  The conditions required for generating a fossil are thought to be mighty uncommon -- most animals don't leave any traces at all, only a few years after they die, so it's likely that the vast majority of the living things that have ever existed aren't represented in today's fossil record.

So the number of species we know about are far outnumbered by the ones we don't know about.  Meaning that as bizarre, fascinating, and wonderful as are the prehistoric animals we've classified, if we were to time-travel back to whatever epoch you choose, we'd find ones more bizarre still.  And that's even including a banana-fanged predator the size of a polar bear.

All of which puts me in mind of the last sentence of Charles Darwin's Origin of Species, which seems a fitting way to end:

There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

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Monday's post, about the institutionalized sexism in scientific research, prompted me to decide that this week's Skeptophilia book recommendation is Evelyn Fox Keller's brilliant biography of Nobel Prize-winning geneticist Barbara McClintock, A Feeling for the Organism.

McClintock worked for years to prove her claim that bits of genetic material that she called transposons or transposable elements could move around in the genome, with the result of switching on or switching off genes.  Her research was largely ignored, mostly because of the attitudes toward female scientists back in the 1940s and 1950s, the decades during which she discovered transposition.  Her male colleagues laughingly labeled her claim "jumping genes" and forthwith forgot all about it.

Undeterred, McClintock kept at it, finally amassing such a mountain of evidence that she couldn't be ignored.  Other scientists, some willingly and some begrudgingly, replicated her experiments, and support finally fell in line behind her.  She was awarded the 1983 Nobel Prize in Physiology and Medicine -- and remains to this day the only woman who has received an unshared Nobel in that category.

Her biography is simultaneously infuriating and uplifting, but in the end, the uplift wins -- her work demonstrates the power of perseverance and the delightful outcome of the protagonist winning in the end.  Keller's look at McClintock's life and personal struggles, and ultimate triumph, is a must-read for anyone interested in science -- or the role that sexism has played in scientific research.

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

Plausible deniability

One of the things I've never understood is the certainty a lot of people have that the universe is designed in such a way as to line up perfectly with their personal opinions.

It crops up fairly regularly in religion.  You think gays are icky?  Well, what a coincidence.  God doesn't like them, either!  You would rather that the power structure keep men in control of everything?  How about that, Allah would like that, too!

It'd be kind of an odd coincidence, don't you think?  Conservatives think god is conservative, liberals think god is liberal.  Never once do you go to a conservative church and hear the preacher say, "Sorry, brethren and sistren.  God told me that we need to welcome in illegal immigrants."  Nor do you go to a liberal church and hear, "God has a new directive.  Balancing the federal budget is more important than funding social programs."

Doesn't it seem like people are designing their religious beliefs so that they support their political biases, and not the other way around?

To be fair, there are exceptions, such as Reverend Danny Cortez of the New Harmony Community Baptist Church of Los Angeles, who recently broke with the party line of the Southern Baptist Convention and came out in support of LGBT individuals.  But it's rare.  Most of us are convinced we live in a comfortable little universe that in the Big Picture, works exactly the way we would like it to.

This tendency isn't confined to religion, though.  A study done at Duke University and published just this month supports the troubling notion that we even approach scientific findings this way.  Troy Campbell, a Ph.D. candidate in Duke's School of Business, and his team found that when test subjects were presented with scientific evidence of a problem, followed by a policy solution that would run counter to their political beliefs, they were more likely to believe that the problem itself didn't exist.

[image courtesy of the Wikimedia Commons]

Conservatives, for example, were given a statement to read that showed evidence that the global average temperature would rise by 3.2 degrees in the 21st century.  Half of them then read a proposed solution requiring increased government regulation -- carbon emissions taxes, restrictions on fossil fuel use, and so on.  The other half were given a solution that involved support of the free market, such as reducing taxes on companies that use green technology.

When asked whether they believed that the Earth's temperature would rise by the predicted amount, only 22% of the first group said they did -- compared to 55% of the second group!

Liberals are no less prone to what Campbell calls "solution aversion."  Liberals showed a much lower belief in statistics about violent home break-ins if they were then presented with a solution that doesn't line up with liberal ideology, such as looser restrictions on handgun ownership.

"Logically, the proposed solution to a problem, such as an increase in government regulation or an extension of the free market, should not influence one’s belief in the problem.  However, we find it does,” Campbell said about the study.  "The cure can be more immediately threatening than the problem...  We argue that the political divide over many issues is just that, it’s political.  These divides are not explained by just one party being more anti-science, but the fact that in general people deny facts that threaten their ideologies, left, right or center."

All of this strikes me as kind of bizarre.  Whatever my other biases, I've never thought it was reasonable to deny that the disease exists because the cure sounds unpleasant.  But apparently, that's the way a lot of people think.

But it does give some hope of a solution.   Says study co-author Aaron Kay:  "We should not just view some people or group as anti-science, anti-fact or hyper-scared of any problems.  Instead, we should understand that certain problems have particular solutions that threaten some people and groups more than others.  When we realize this, we understand those who deny the problem more and we improve our ability to better communicate with them."

To which I can only say: amen.