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I am a politically-progressive, ethically-herbivorous anthropoid pursuing a paleontology education in the Los Angeles Basin. I am largely nocturnal, have rarely been photographed, and cannot thrive in captivity.

27 August 2011

Did Veganism Kill The Nutcracker Man?

The short answer is, "no." I almost filed this one under Idiotic Omnivore Claims, but realized that wouldn't be fair. The misunderstanding is just a function of how slowly scientific information gets spread into the public consciousness.

And now, you're wondering what I'm talking about.

The Claim: Paranthropus robustus was driven to extinction because its specialized "vegan" diet prevented it from adapting to changing climate. Or so I was recently informed by manowar40 in a YouTube comments section. His contention is that Homo was able to adapt to drying climate because of our omnivorous diets, while P. robustus was so dependent on a "vegan" diet that it died out.

It would be easy for me to dismiss this as just another misinformed omnivore on his high horse, but that's only because I'm a geek who reads paleontology journals. In other words, he doesn't follow all the latest research, and just relies on informed third parties to fill him in. And there's nothing wrong with that; it doesn't make him a dumbo at all.

It's just that his sources, whoever they are, are a bit behind the times.

True, it used to be the consensus that P. robustus died off because of a specialized diet. The reason for this assessment is that the paranthropines had big, flat, thick-enameled molar teeth and huge jaws, usually a sign of specialization to hard, brittle foods like nuts and seeds (hence, the nickname "Nutcracker Man," given to P. boisei, a close relative of robustus). Genus Homo has more generalized masticatory adaptations, reflecting a wider variety of food strategies.

Or so the reasoning used to go. That was before we started doing laser ablation stable isotope analysis, a method that allows us to analyze extremely small areas of carbonates and phosphates (on the order of 10 micrometers) in situ; that is, without having to crush and reprecipitate them. The method
allows for finer spot analysis than had been possible previously with traditional methods that required the homogenization of large amounts of material. The major advantages of this technique are that it is essentially nondestructive and requires little sample preparation.
With the laser ablation method, we're able to not only tell what isotopes a fossil organism was absorbing from its food, but also get a pretty good idea what sorts of food it was eating over its life, because we can look at the actual wear patterns on its tooth enamel and correlate them with the isotope evidence over time and geography.

Doing this with the teeth of a P. robustus sample from Swartkrans, South Africa, Sponheimer et. al. reached a surprising conclusion (emphasis mine):
laser ablation stable isotope analysis reveals that the d13C values of Paranthropus robustus individuals often changed seasonally and interannually. These data suggest that Paranthropus was not a dietary specialist and that by about 1.8 million years ago, savanna-based foods such as grasses or sedges or animals eating these foods made up an important but highly variable part of its diet.
They elaborated on the then-common idea that this species' extinction had been due to its presumed specialized diet (emphasis mine):
A dental microwear study of the earlier (3.0 to 3.7 Ma) hominin Australopithecus afarensis found no evidence that its diet changed over time or in different habitats (20). In contrast, stable carbon isotope (3, 4) and dental microwear texture analyses (1) of the slightly younger (~3.0 to ~2.4 Ma) hominin A. africanus demonstrated that its diet was far more variable. This suggests the possibility that a major increase in hominin dietary breadth was broadly coincident with the onset of increasing African continental aridity and seasonality after 3 Ma (21, 22) and only shortly antedated the first probable members of the genera Homo and Paranthropus (23–25) and the earliest stone tools (26). The undoubted toolmaker Homo is thought to have been a dietary generalist that consumed novel foods such as large ungulate meat and tubers that are abundant in savanna environments (27–30). Paranthropus, in contrast, with its extremely large and flat cheek teeth, thick enamel, robust mandible, and heavily buttressed facial architecture, is often portrayed as a dietary specialist (27–29). Further, it has been argued that this specialization contributed to its extinction when confronted with increasingly dry and seasonal environments later in the Pleistocene, whereas Homo’s generalist adaptation was crucial for its success (28, 29). Our results suggest that Paranthropus had an extremely flexible diet, which may indicate that its derived masticatory morphology signals an increase, rather than a decrease, in its potential foods. Thus, other biological, social, or cultural differences may be needed to explain the different fates of Homo and Paranthropus (31).
In other words, their evidence suggested that both Paranthropus and Homo had inherited an omnivorous habit from their shared australopithecine ancestor. And further, that P. robustus' "specialized" teeth and jaws reflected not a restriction of its eating abilities, but an expansion of it.

This paper strengthened and confirmed a conclusion reached two years earlier by Wood & Strait:
We suggest that although the masticatory features of Paranthropus are most likely adaptations for consuming hard or gritty foods, they had the effect of broadening, not narrowing, the range of food items consumed. It is possible that these adaptations allowed Paranthropus to become a “seasonal specialist” by exploiting previously unavailable fallback food items during periods of dietary stress (Conklin-Brittain et al., 1988). One of us (e.g., Wood and Ellis, 1986), and many others, have wrongly interpreted the derived morphology of the masticatory system of Paranthropus as evidence for stenophagy. Instead, the vast majority of the evidence suggests that the masticatory system of Paranthropus is more consistent with euryphagy. Thus, the extinction of Paranthropus species should not be considered a straightforward consequence of having an overspecialized diet.
Both papers have been cited fairly robustly (if you'll pardon the pun), and when I ask around among my anthro friends, it seems that this interpretation is shaping up to be the standard view of Paranthropus robustus.

What happened here is simple: whoever manowar40's been getting his paleo information from is behind the learning curve. That's not mano's fault, and it doesn't quite add up to an Idiotic Omnivore Claim because it's not exactly a claim that's detached from reality.

It just shows that scientists need to do a better job of communicating their work to the general public.

26 August 2011

Rat Race Or Living Space: What Really Drives Evolution?

Everyone (even Darwin) knows evolution is all about competition. And everyone (even Darwin) might be wrong, at least when it comes to land animals.

That's the conclusion reached in a paper published last year in Biology Letters: Links between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land.

The authors conclude:
The data support the growing evidence that, except following mass extinctions, tetrapod diversity was primarily achieved by unrestricted expansion into empty ecospace, that is by the filling of unrealized modes of life, and multiplying into already realized modes. As taxonomic diversity has increased, there have been incentives for tetrapods to move into new modes of life, where initially resources may seem unlimited, there are few competitors and possible refuge from danger. And as ecological diversity increases, taxa diversify from their ancestors at a much greater rate among faunas with more superior, innovative or more flexible adaptations.
In laymen's terms, they're saying that evolution is driven not by competition, but by the lack thereof, when species escape direct competition by moving into new, unoccupied niches.

The dearth of evidence supporting large-scale biotic replacements driven by competition is nothing new; as the paper notes, Stephen Jay Gould noticed this back in1980, and he wasn't alone. And it's long been understood that when selection pressures are eased (say, by moving to another ecospace), all species will over-reproduce (which probably increases adaptive opportunities). What's new here is the bold claim that this expansion of opportunities, rather than the constraint of competition over resources, appears to be a prime mover of tetrapod evolution.

The paper has since been cited only six times on Google Scholar, including in one paper published just today. So, it's still too early to tell whether its assessment will have a major impact in our understanding of evolution. But the hypothesis instantly appealed to me, so I am going to keep an eye on it.

Reading it, my first thought was that someone ought to test the hypothesis by applying it to hominin evolution, and see whether the diversification of australopiths and their descendents in the Plio-Pleistocene follows the same pattern. That's when hominins moved out of the forests and onto savannah and woodland biomes... niches that had no prior hominoid primate presence. If it held up at this smaller scale, the hypothesis would receive some firmer experimental support, and also potentially shed some light on just what it was, precisely, driving the rapid hominin evolution of this time period.

That question, in case you didn't know, is the big mystery of human evolution, particularly the evolution of our freakishly large brains. Could our big brain be a consequence of the sudden expansion of hominin eco-space, a brain born out of opportunity rather than struggle? It's certainly romantic to think so. But romance won't cut it in science.

As far as I can tell, no one has run such a test yet. I'd like it to be me, but I currently lack the resources and full training to do it properly. I'll just have to keep my eyes peeled and hope that no one gets to it before I do.

21 August 2011

A Reason To Get Out Of Bed

And then, there is good news, too. But this time on a personal scale.
"We are happy to inform you that Rocco was recently placed in a safe, loving and permanent adoptive home. We know that you will miss him as we do, but hope it makes you happy knowing that his adoption opens our doors to one more suffering animal who desperately needs refuge."
That's good news I received in the mail yesterday about my pet dinosaur, previously of Animal Acres Farm Animal Sanctuary in Acton, CA, a piece of paradise if ever there was one. My sponsorship donation is now being used to pay for the care and upkeep of another lovely theropod, Lila, who was rescued in 2008 after being abandoned at a factory farm.

Go to their site and become a member today. Or do the same at a farm sanctuary near you. It's one of the most immediate and intimate things you can do to help an individual farm animal, and most such sanctuaries will allow you to visit with and get to know your new friend.

I got to meet Lila last weekend, and I'm glad I made the drive. Although at the time, I hadn't gotten the above mail yet, and so was a little distressed that I was unable to find Rocco. I'm glad to hear that he is safe and loved, and that I got to meet Lila. I hope she will find some happiness, too.

Gator Power: Meaner Than A Gator

File this one under "can doesn't mean should": Alligator fat could be used to make biodiesel.

The shocking thing to me was the sheer size of the alligator meat industry: it "disposes of" 15 million pounds (!!!) of alligator fat in landfills every year. That seems to be separate from the gator skin industry, though I could be wrong. Gators are already victims of factory farming for their skins: 
Other “exotic” animals, such as alligators, are factory-farmed for their skins and meat. Young alligators are often kept in tanks above ground, while bigger animals live in pools half-sunken into concrete slabs.(5) According to Florida’s regulations, as many as 350 6-foot alligators can legally inhabit a space the size of a typical family home.(6) One Georgia farmer had 10,000 alligators living in four buildings, where, according to the Los Angeles Times, “hundreds and hundreds of alligators fill every inch of [each] room.”(7) Although alligators can live up to 60 years, farmed alligators are usually butchered before the age of 2, as soon as they reach 4 to 6 feet in length.(8,9) Humane treatment is not a priority for those who poach and hunt animals to obtain their skin or for those who transform skin into leather. Alligators on farms may be beaten to death with hammers and axes, sometimes remaining conscious and in agony for up to two hours after they are skinned.(10)
 The last thing they need is a discovery like this to provide an incentive to escalate cruelty to alligators.

Some days, I just don't want to get out of bed.

19 August 2011

Rewinding Evolution At Chickens' Expense; And A New Living Fossil

Here's what was at the top of  my Google alert this morning: Scientists altered DNA to create snouted chicken.

Exciting, troubling and totally amazing all at once, if true. Although the scientists didn't alter the DNA at all; they simply altered the development of the DNA in the egg. People -- including, apparently, intrepid science reporters at MSN News -- misuderstand what DNA is and what it does, and so we end up with sloppy phrasing like this headline and some of the sentences in the article itself.

All that happened here is that the team counteracted the development of one molecule and activated another -- both of them already present on the DNA strand -- by adding a protein to the embryonic environment. The chicken DNA remains unchanged, and it is only the expression of that DNA that gets altered.

This isn't genetic engineering, where scientists splice DNA from two different species together to produce a new one. No one imposed alien DNA on these chicken embryos to produce maniraptoran traits. They simply verified the hypothesis that chickens -- and all other birds -- are, in fact, dinosaurs.

Now, I'm not opposed to genetic research, or even genetic engineering per se; like any other tool, it will have both positive and negative consequences. Our job as activists and citizens is to monitor that tool, minimize the negatives and allow the positives to flourish.

Having said that, though, and as neat a trick as the paleontologist side of me thinks this is, it's just that... a trick. It hasn't really told us anything we didn't already know, and strikes me, on the whole, as frivolous at best, cruel at worst.

But, in less-invasive paleo news this week, we've discovered a new/old "living fossil" eel in the Pacific, a primitive taxon now dubbed Protoanguilla palau.  I have to say, the deeper into evolution I get, the more I am loving "fish." For the past few months, I've been seriously considering an effort to forge a future for myself in fish paleontology. Fish are such deeply misunderstood and underestimated creatures among the general public that it's difficult to convince people that we shouldn't exploit and eat them, either.

But then, you already know fishing hurts.

14 August 2011

More On Miocene "Apes"

It's not that I don't trust you. I know I included a link in my last post to an article about a time when Earth really was the Planet of the Apes. And I hope you read it. But I still can't stop thinking about it. For about the third or fourth time in my life, I've started going ape for the Miocene apes.

Of course, "apes" don't really exist. That's an old, pre-cladistic term that we paleo students and professionals call a paraphyletic taxon, because it usually excludes the direct human lineage, who sprouted from the same common ancestor. A more proper term would be "Miocene hominoids," but let's face it, when's the last time you called that boorish meat-head who's always trying to muscle you out of the way and steal your mate a "big dumb hominoid"?

It'll never catch on.

So, apes it is. You might think you know what "ape" means, so I'll get back to that in a sec. First, let's talk about this word "Miocene."

As mentioned in my post about giraffes, the Miocene Epoch was a time of great tectonic, climatic and ecological change that proved a crucible of evolution for many lineages. At its start, about 23.8  Ma, the non-avian dinosaurs had already been extinct for 42 million years. Avian dinosaurs (aka, birds) and mammals flourished in their absence, expanding into all terrestrial niches. Mammals had returned to the sea, and were starting to develop their special brand of echolocation (like "apes," cetaceans reached the period of their greatest diversity during the Miocene). Grasses and kelps were radiating into new regions, while the planet's tectonic plates were coming close to their current positions (although South America and North America were not yet connected, and India was only beginning to collide with Eurasia). The uplift of the Andes and Himalayas mountains and the closing off of the Tethys Ocean slowly but radically altered Earth's climate, so that by the end of the Miocene, many animals had been forced to migrate to mid-latitudes as the world got colder.

At the start of the Miocene, monkeys were the biggest game in town among the primates. At the end, they had been supplanted by the apes, who had already begun to evolve into our direct ancestors.

When I was a kid, I used to call the Miocene "the Age of Apes," to make it sound equal to the "Age of Dinosaurs." Mostly, that was human bias talking, but there's still some justification for the name (provided you pay no never-mind to those cetaceans and grasses staking their claims): apes reached the height of their diversity in the Miocene, radiating across Eurasia and Africa into nearly 100 different species. Sadly, most of them went extinct as the Miocene climate got steadily colder, and the survivors fled to Africa and southern Asia, where they became gorillas-chimps-humans and gibbons, siamangs and orangutans, respectively.

When most people think of an ape, they imagine either a knuckle-walker like the gorilla and chimp, or a tree-swinger like the gibbon and orangutan; but the apes of the Miocene were more diverse than that. They had mastered just about every form of terrestrial locomotion except flight and bipedalism... and we're not sure about bipedalism.

But I'm putting the monkey ahead of the banana here.

What's In An Ape?
It's common to use the words "monkey" and "ape" interchangeably, but this isn't quite accurate. Apes diverged from a monkey-like common ancestor a long time ago, most likely before the Miocene began, and there are numerous anatomical differences between them. Notably, apes have no tails and larger brains in relation to body size than monkeys do. Their arms are longer and, along with their hands, more flexible than those of monkeys. Some people get confused here, though, because when you look a little more closely, you find that apes have many things in common with some monkeys, but not others. Usually, the monkeys who share traits with apes are called "Old World" monkeys (because they're found in Africa and Eurasia), and the ones who don't are called "New World" monkeys (guess where they come from?).

Apes share a common ancestor with Old World monkeys, and together with them make up a group of primates called the Catarrhines, who are characterized by their downward facing nostrils and tails used for balancing rather than grabbing. New World monkeys form a group called the Platyrrhines, or flat-nosed monkeys.

The lines of the Catarrhines and Platyrrhines diverged from each other about 40 million years ago, when a group of Platyrrhine ancestors somehow made it across the Atlantic Ocean to South America, in one of paleontology's biggest mysteries. We're still nowhere close to figuring out how that happened.

So, apes are monkeys, sort of, because they are Catarrhines and display most of the Catarrhine characters. Except that "monkeys" aren't really monkeys, since there are two independent lineages who diverged from some common ancestor that wasn't quite a monkey,  either.

Got that? Good, because there will be a quiz.

The main point I'm working up to here is that most people today, if pressed to describe how an ape moves, would say either, "walking on their hands and feet" or "swinging from trees." Those of more precise observatory skills would point out that ground-walking apes specifically walk on their knuckles rather than their palms, and tree-dwelling apes get around by hanging and swinging below branches rather than on top of them. These methods are distinct ways of movement among living apes, so there's a temptation to define the group "apes" by them.

But just as, paleontologically, giraffes are not defined by their long necks, "apes" aren't defined by these ways of moving. And for the same reasons: most of their ancestors didn't do it that way.

The earliest true "ape" (whom you met in my hokey screenplay spoof) was Proconsul africanus, a hominoid who lived between 25 and 15 Ma in the forests of east Africa, but had cousins all over Eurasia, as well. If you saw a Proconsul today, you'd probably think it was a giant tailless monkey, because like monkeys, it walked with its body parallel to the branches (rather than swinging perpendicularly below them like gibbons and orangs) and walked on its palms (instead of its knuckles like chimps and gorillas). The technical term for this is "pronograde arboreal quadrupedality."

P. africanus retained several monkey-like features, such as thin tooth enamel, a narrow torso and relatively short arms. But its brain was larger than those of monkeys relative to body size, and it lacked a tail. Since Catarrhines used their tails for balance, their hominoid descendants had to find a way to compensate for this ability upon losing their tails. That's where their hands and feet come in.

Proconsul's hands and feet are distinct from those of monkeys in that their first rays are well-developed and their phalanges are elongated. In layman's terms, Proconsul had more flexible wrists, ankles, fingers and toes than other Catarrhines, and used them rather than a tail to balance themselves.

P. africanus and the other members of its genus represent the basal-most "ape" body plan, the foundation from which subsequent species evolved increasingly diversified and specialized forms of locomotion, including the knuckle-walking of chimps and gorillas, the tree-swinging of gibbons and orangs, and the obligate bipedality of humans.

Understanding this point about Miocene hominoid locomotion is important, because a lot of people tend to think that evolution stood still for apes while it marched onward for humans. They imagine that our common ancestor with, say, chimps was basically a chimp. But chimps have been diverging from the common ancestor for 6 to 7 million years, just like we have. Unfortunately, the fossil record of chimp evolution is currently poor, but it's likely to contain as many extinct intermediaries as the human one does, possibly even with as much diversity.

The same is true for all other apes, extant and extinct. Various traits of the still-living hominoids -- including precision grasping and a possible form of bipedalism -- all have their precursors among the Miocene apes, who added in many other locomotive and dietary specialties no longer found among the living "great apes."

Since this post is getting a bit long for my preferences, I'll end it here. But this won't be the last you hear of the Miocene apes. I'll do future posts on many of them individually.

Meanwhile, please do not neglect the ape protection and rescue links I provided in my previous post. If no other animals deserve "rights," the apes most certainly do.

13 August 2011

Rise Of The Planet Of The Apes: Been There, Done That

Look, Hollywood, I get it, OK? I understand you've got to get butts in seats, and so feel the need to erect -- or resurrect -- franchise tent-poles every year. But would a little originality now and then be too much to ask?

I mean, c'mon: apes rising up to conquer the world? What a bunch of hackneyed Miocene tripe!


An idyllic jungle scene, erupting with the full spectrum of the rainbow, something out of a Disney movie. Animal calls abound. Familiar-looking, colorful birds flutter about among gorgeous flowers and bright green leaves. The wind rolls through and rustles the foliage aside, revealing a huge cluster of STRANGE, BRIGHTLY-COLORED FRUIT, hanging succulently from the branches, making our mouths water.

We're not alone in that reaction.

Suddenly, we hear a chorus of joyful HOOTS and GRUNTS, presaging the arrival of a band of CATARRHINE MONKEYS, who scamper elatedly across branch-tops, driving away the roosting birds.

There's an arrogance to these almost-familiar monkeys, with their downward-facing nostrils and tails used for balance rather than grasping. They've ruled the primate world for millions of years, and they know it. They want the fruit, and there is no one to stop them.

Except each other. A fight breaks out when it becomes clear there isn't enough fruit to go around. Rocks and bark are thrown. Teeth are bared in screeching contests. Loose leaves rain down from the canopy as the treetops shake from the monkey fight. And finally, there is a victor.

One relatively big male -- we'll call him HANUMAN -- wins the day, with the help of his betas. They form a defensive ring around the fruit, holding off the other bands of monkeys. Their females, some with babies clinging to their fur, come out of hiding, to groom the males and share in the spoils of war.

HANUMAN perches on a high, sturdy branch, as though he's about to give a speech. The others look on with admiration, especially the younger males who envy his position and access to mates.

Though he speaks in hoots and grunts, we can still understand him.
Brothers, friends, wives, lend me your ears. You fought well, and deserve these sweet treats. But we must conserve our strength.
Finally ready to give up some wives, eh, old man?
The other males let forth with hearty monkey-laughs.
No, young one. I'm as strong as ever. But if we are not careful, we will all have to give up more than wives. Maybe everything.
This gets everyone's attention.
There's a new creature in our forests. A giant who has come from far away to take our fruits and our bugs and our trees. And he is not alone.
Bah! More fear-mongering from an old tyrant. Have you seen these giants, Hanuman?
HANUMAN cuffs the BRASH YOUNG MALE, silencing him.
No, but others have. It is said they walk like monkeys, but they have no tails. And their arms are too long. And their faces... I am not ashamed to admit, brothers, that I am concerned. Long we have ruled these forests, but I fear our days are ending.
(now out of cuffing range)
Phish! I'll believe it when I see it, old fool.
Other young males hoot their agreement. HANUMAN scowls, ready for a challenge from the BRASH YOUNG MALE, who's puffing his chest and baring his teeth, posturing for a fight.

They circle each other, male and female monkeys alike making room on all sides. But just as they are about to pounce, something in the air changes.

Everyone senses it, and freezes in their tracks. The hooting stops, so they can all be sure they hear it.

Over there! And there! All around them, it's coming through the trees. Something big. And it is not alone.

The monkeys forget their quarrel, and pull in close to one another, HANUMAN and BRASH YOUNG MALE now united in common defense of their band. They all take slow steps back, until they're pressed against each other and can go no farther.

That's when it comes out of the forest, slow, confident, arrogant as a monkey and twice as cunning. It does not need to push aside the leaves and branches; instead, they simply seem to flow around him.

After a beat, others like him follow. They have the monkeys surrounded.

These new creatures look half-monkey, half-something-else. They walk on the branch-tops, using the palms of their hands and the soles of their feet, like monkeys do. Their hips move in monkey-like fashion, too, but are more flexible. 

And there are differences that set them dramatically apart. First, and most obviously, they have no tails, and this accounts for the strange grace of their movements. Their bodies achieve balance in the treetops through other, more subtle structures. Their arms are too long. Their hands and shoulders seem more pliable, with greater ranges of movement. And their faces, too, are all off-kilter compared to the monkeys, in subdued and awful ways.

Alone, these differences would not stand out. But taken together, they make something completely new, and completely alien to the Miocene world.

These are the first apes.

Their leader, an old and powerful-looking gray-hair, steps forward with the self-assurance of a natural ruler. We'll never know his real name, but one day we'll call him, and his people, PROCONSUL.
We have not come to fight, friend monkeys, but be assured, we will if we must. I know we look strange to you, but we are brothers nonetheless.
Then why do you steal our food, brother?
Steal? The food is ours. As is the land, though we come from far away. We are the first of our kind, but we will not be the last. 
HANUMAN puts up a good show, enough to save face with the monkeys. But PROCONSUL cuffs him, and it's clear this fight is over before it started. The monkeys all hang their heads in shame... all except HANUMAN, who nonetheless looks away.
There is no shame in standing aside. You have been good stewards of the land, but your time has passed. That is the way of things. Just as you assumed the mantle from the tarsiers, now we assume it from you. The age of monkeys is at an end. The world now belongs us.
At a gesture from PROCONSUL, the apes make room and let the monkeys pass. One by one they leave, mourning the end of their supremacy, fading into the background of the jungle.

HANUMAN is the last to go. He dares one last moment of eye contact, and hands PROCONSUL the juicy FRUIT he'd been defending.

PROCONSUL nods his thanks, and lets the King of the Monkeys go to his people.

When the monkeys have gone, PROCONSUL looks to his fellow apes and smiles. They all hoot and screech triumphantly as he hands out the fruit.

Truly, it is a new world...
So, you've probably figured out by now that this isn't a review of the new James Franco vehicle in which uplifted and put-upon apes launch a revolution by attacking humans during rush hour (at our most vulnerable!).

And I'm not going to post any such review. I'm not even sure I'm going to see the movie, at least in a theater. But I will confess to being perversely interested in it, for two reasons.

1) It looks like it has an anti-vivisection message (though it'll probably be of the typical, reactionary Hollywood science-phobic variety, and not one that makes people think about the ethics of animal experimentation); and,

2) It's gotten me fired up about an old paleo-passion of mine: the Miocene apes, who dominated Eurasia for millions of years, radiating into possibly 100 different species in 40 genera, including the lineage who eventually migrated back into Africa and became us. This was the real "rise of the planet of the apes," and it's one of the most fascinating periods of mammalian evolution, to boot (don't let the corny screenplay above dissuade you).

So, in a shameless attempt to capitalize on Google searches for the movie's title, here are some great links about both subjects.

Learn about the true Planet Of The Apes. Way cooler than the movies.

And then, stick your neck out and do something to help preserve the apes we still have left.

05 August 2011

Idiotic Omnivore Claims

Yes, it's not just (some) vegans who wear their ignorance of biology and evolution like a badge of honor. Turns out, paleos can also drink from the Well of Evo-Woo. Try to contain your shock.

See, seems there's a meme floating around in some omnivore circles that personifies the title of this post: namely, that human production of hydrochloric acid in the stomach is proof that we are "meant" to eat meat, because herbivores don't produce HCl in their stomachs.

I've encountered it three times in online comments sections; once at Let Them Eat Meat; once at The Huffington Post; and most recently on the comments of a YouTube video featuring Jonathan Safran Foer. I've stopped counting the number of times I've heard it from meaty-mouths here in meatspace.

But, I did start to wonder where this embarrassingly moronic claim originated.  So, I've been trawling the depths of Google and Bing on my quest to find out, and I think I nailed it down.

From what I can tell, the meme got its start with The Myths Of Vegetarianism by Dr. Stephen Byrnes. Check out paragraph 2 of his Myth #11:
Some vegetarian groups claim that since humans possess grinding teeth like herbivorous animals and longer intestines than carnivorous animals, this proves the human body is better suited for vegetarianism (123). This argument fails to note several human physiological features which clearly indicate a design for animal product consumption.
First and foremost is our stomach's production of hydrochloric acid, something not found in herbivores. HCL activates protein-splitting enzymes. Further, the human pancreas manufactures a full range of digestive enzymes to handle a wide variety of foods, both animal and vegetable.
Further, Dr. Walter Voegtlin's in-depth comparison of the human digestive system with that of the dog, a carnivore, and a sheep, a herbivore, clearly shows that we are closer in anatomy to the carnivorous dog than the herbivorous sheep. (124)
I don't know much about Byrnes; he's described as a naturopathic doctor (warning klaxon #1), recommended the Weston Price Foundation (klaxon #2... and no, I will not link), and apparently did good work for HIV/AIDS patients in Hawaii (genuine applause) before dying suddenly of a stroke in 2004. Nor do I know where Byrnes came up with this silly idea about herbivore digestion. But since the encounters I've had with this meme have all been worded almost exactly like the emphasized paragraph above, I think I can safely blame Byrnes for giving this one legs.

He should have known better, and shame on him for starting it. More shame on those in "paleo" circles who should also know better and should have corrected him on this point long ago. I mean, they wouldn't want to embarrass themselves and their cause by spouting provably false information and then getting publicly called on it, would they?

Like suffering and empathy, gastric secretion of HCl is conserved in all vertebrates. Without knowing which specific digestive enzymes Byrnes was referring to (though I suspect it's elastase, which I've heard more than one carnist apologist invoke), I can still safely predict that the same is true for his pancreas claim, as well.

To put it plainly: yes, herbivores do produce hydrochloric acid in their stomachs. So do carnivores and omnivores. There's nothing particularly noteworthy about it; it's just part of all vertebrates' fishy ancestry.

The fact Byrnes was pointing to, without seeming to realize it, is that carnivores and herbivores produce differing amounts of HCl, reflecting their different trophic strategies. Hominins fall here, as in most other ways, somewhere in the middle range, making them generalists or "omnivores." Which is a perfectly valid point to make when arguing against the "man-is-a-natural-vegan" claim; it's too bad a guy with a Dr. in front of his name didn't possess enough of a grasp on basic biology to spot such a simple error, and thus lured himself and his readers into looking like bozos. But then, that's what you get for credential-mongering.

Fact-checking: it's the science-y thing to do, friend paleos. Given your self-chosen moniker, you guys really ought to be more careful. Call this one a gift.

NOTE: I'm not planning on Idiotic Omnivore Claims becoming a regular feature at PaleoVeganology, but I will keep my peepers peeled nonetheless.