Giants in a Giant World: Why Were Dino’s So Darned Big?

Brontosaurus-Triceratops

Dinosaurs were big, some of them were monstrous.  But, how is that even possible?  Aren’t there natural constraints on size that prevent our own big mammals from getting to the size of buildings?

There are a few key problems that have contributed to what is known as the Dinosaur Paradox.

Cromercrox tries to hash it out:

First, the digestion …

Sauropods swallowed enormous amounts of low-quality food that simply composted in their enormous bodies. The food wasn´t processed in the complex ways seen in ruminants or rabbits – it just went in the thin end, down to the thick middle, and took a long time to digest. As every gardener knows, the best and most efficient compost heaps are also the largest, so large gut volume combined with an active microflora and long retention times means an emphasis on size. Sauropods were gigantic walking compost heaps. (And I bet they farted like anything).

But wait, there´s more.

Indeed there is.  As I mentioned in an early article on whether dinosaurs were warm blooded, the lungs that these beasts had are quite different than ours (and other mammals).  Basically, they have the lungs of birds – air sac lungs.  These would have aided in the expelling of the enormous amount of heat generated by the fermentation process we talked about above.

Unlike mammals, which have a simple set of lungs that pulls air in and expels carbon dioxide, birds have a complex series of air sacs, accessory to the lungs, which penetrate many parts of the body, including the bones. At least some dinosaurs are known to have similar arrangements. The apposition of air sacs to the surfaces of the gut in sauropod dinosaurs would have allowed for the transfer of terrific amounts of excess heat, dumped through to the wet surfaces of air-sac membranes and converted into water vapour. Another constraint on size, lifted.

The last reason sited for their excessive size is reproduction.  Unlike the modern form of large animals like elephants and hippos, dinosaurs laid eggs.  This meant that it was easy to create new ones.

Sauropods were hard to kill not just because they were big, but because replacing them was relatively easy  – just lay a pile more eggs and bury them, the work of a moment, rather than incurring the energetic and temporal costs and life-historical limitations of gestation. Another constraint lifted – sauropods could grow bigger in a given environment, because making more of them was easier; they fed full-time on low-quality browse which they took time to digest (another incentive to grow larger) without having to chew it (ditto) and because of their bird-like structure, they were good at dissipating excess heat (the same) and were relatively lightly constructed (the same again, with a bag of crisps, please).

Bada-bing, bada-boom!  You get big-ole dino’s roaming the earth.

What he didn’t mention was that the earth had a far thicker atmosphere during this time.  In fact, during the time of the Mesozoic it is often compared to the thickness of water! Sure, it would feel different because air is not water. But, the thickness would be similar. While this could not account for all of the size issues (as even with the buoyancy of water, the shear size of these guys was still ridiculous), when combined with the above data, it helps to explain how the biggest of the biggest got so darn big.

Is Kin Selection Dead?

Nature-ants

None other that E.O. Wilson, father of Sociobiology, and one of the greatest minds in Biology of the last half-century says that it’s time to dump the idea of kin selection:

"We hope our new theory for the evolution of eusociality will open up sociobiology to new avenues of research by liberating the study of social evolution from mandatory adherence to kin selection theory. After four decades ruling the roost, it is time to recognise this theory’s very limited prowess."

Kin Selection, as defined by John Maynard Smith (the great mathematical biologist, and likely the inventor of the term) is:

By kin selection I mean the evolution of characteristics which favour the survival of close relatives of the affected individual, by processes which do not require any discontinuities in the population breeding structure.

Say what?

This is a better one:

It seeks to explain why individuals take the seemingly paradoxical step of sacrificing their own reproductive potential in order to care for the offspring of relatives.

OK, think of ants. Worker ants will do all kinds of crazy stuff that results in their death in order to increase the likelyhood that the queen ants can continue to breed.  This SEEMS like a bad idea on the part of the worker ant, since from his own perspective … he’s dead.

The idea, then, has been that over time, the genes of the species evolved in such a way as to cause certain members of the same family-line to sacrifice themselves so that others can breed.  Since they are kin, they share a large portion of their genomes, and therefore it is believed that the sacrifice isn’t actually all that crazy, since the sister will be passing on what basically amounts to YOUR genes.

Kin selection has been the dominant method of explaining the eusociality of hierarchical species such as ants, bees, and even wolves and humans.

What’s amazing here is that Wilson has been a long-time backer of kin selection theory.   So, to see him pull back is something interesting. I’m not sure if I agree with him yet. But, he ain’t no dummy.

100th Four Stone Hearth Blog Carnival

piltdown-men

What happens when you stuff an Orangutan jaw into a human skull?  You get a great hoax to perpetuate on the scientific community that lasts for 30+ years! 

The Piltdown hoax is only one of the many great articles featured in this 100th “episode” of the Four Stone Hearth anthropology blog carnival

Mosque Madness Continues

Ground Zero Mosque

Aziz Poonawalla makes a compelling argument in favor of the building of the Mosque in NYC:

[I]t really does boil down to an issue not just of religious freedom but also a means of putting into practice the very American values which Al Qaeda seeks to deny. A mosque in NYC, near to the site of 9-11, is not a “monument to the attackers” (a pernicious claim, which puts collective responsibility for the terrorist attacks on all Muslim Americans) but actually a repudiation of the Al Qaeda ideology. What they want is to make Muslim Americans reject American identity and follow their call to jihad – explicitly, as Anwar al Awlaki has repeatedly stated, and even succeeded (ref the cases of Fort Hood and Times Square). An American mosque, built for American Muslims, is literally the antithesis of what the enemy most desires.

The bigotry unleashed by this whole affair plays perfectly into our enemies’ hands.

The above picture just freaks me out.  What scares me is the fact that humans have the capacity to be so illogical.  We love to toot our own horn as a species – we’re so smart compared to other animals, we’re so superior.  The fact is, we’re a race of idiots blessed periodically with a few people who aren’t quite as dumb who do all of the inventing, writing, thinking, and other braniac stuff. 

Here’s the guys “great logic”.  Ground zero is to Auschwitz what Muslims are to _______ ?  If you answered, “Hitler” you’re correct! Muslims are like Hitler. 

Even if we allowed the metaphor of ground zero to Auschwitz (already a bit strange), the next line hardly follows.  For one, Hitler was one dude who had absolute power over a country, an army, etc.  Islam is a religion that has NO power because it isn’t human.  Only humans have power.  Sure, there are dumb-asses who use religion to justify – post-hoc – their political violence, but that doesn’t make them members of that religion. 

I can say I’m a robot, kill a bunch of people in the name of machine-kind, but that doesn’t make me a robot.  It makes me an insane murderer.

Fucking idiots. 

Whatever, I’m sure this guy doesn’t believe in evolution either, or who knows?  Maybe he doesn’t even believe in gravity!  It’s just a theory, after all …

Here’s a happier picture:

ground zero mosque2

Bubonic Plague Around the Corner?

A new study looks at the history of climate and its relation to the spread of bubonic plague.

Pandemics of bubonic plague have occurred in Eurasia since the sixth century ad. Climatic variations in Central Asia affect the population size and activity of the plague bacterium’s reservoir rodent species, influencing the probability of human infection. Using innovative time-series analysis of surrogate climate records spanning 1,500 years, a study in BMC Biology concludes that climatic fluctuations may have influenced these pandemics. This has potential implications for health risks from future climate change.

 

The plague has been at the heart of many historians theories about how some of the largest changes in European and Asian history have gone down.

Did the Justinian Plague contribute to the terminal weakening of the eastern Roman Empire [2]?

Did the Black Death hasten the collapse of Europe’s feudal system, and the advent of liberalizing moves towards mercantilism, literacy and the Renaissance [3]?

(And was the rise and fall of the Mongol-controlled Yuan Dynasty in China, from the mid-12th to mid-13th centuries, influenced by flickering pre-pandemic plague epidemics in China during that Medieval Warm period?)

Turns out that there’s a growing batch of evidence showing a connection between fluctuations in climate, and incidence of plague.  See the figure:

climate-plague

Here’s their description of the graph:

Modeling the effects of climate on plague. In the top plot, the solid black line represents plague activity in the central Asian rodent population (Y(mean)) over the past 1,500 years, as estimated from the authors’ model of the effects of climate (including via observably correlated vegetation indices) on this natural reservoir (sylvatic) plague activity. The broken gray lines show 95% quantiles and the red line represents the multi-frequency (2 to 60 years) Gaussian moving average. The dark-blue plot represents the long-term (2 to 400 years) multi-frequency mean, with the maximum (upper broken line, Y(max)), minimum (lower broken line, Y(min)) and sum of minimum and maximum (solid line, Y(qu.)). The periods leading up to the Justinian Plague (1), the Black Death (2), the 19th-century pandemic (3) and the Manchurian epidemics (4) are shaded in pale blue. The third plot shows the index of conflict between Chinese and nomad societies (solid black line, War). Below this are shown the coverage of the climatic data used in the modeling: glacial series (blue), tree-ring index (green), and the decadal coverage in the monsoon proxy (brown). Taken from Figure 3d of Kausrud et al. [1].

This type of study is both kick-ass (because of how interesting it is) and frightening! 

Russian History in Pictures

These are some great photographs.  Most of them hovering from around 1910.  In full color. 

Here’s one of the Emir of Bukhara, Seyyid Mir Mohammed Alim Khan, in modern day Uzbekistan.  Awesome outfit. (The ones at the site are larger.)

Emir

Portland Folk Are Just Plain Smarter

Well, if it wasn’t enough that those of us in Portland already suffer from a superiority complex based on our early adoption of biking, going “green” in nearly every way possible, high per capita college degree holding, and abundunt strip clubs (what?) …

It turns out we also read more than everyone else in the nation. 

Multnomah County
has the highest collection turnover rate per capita — meaning its
books, CDs, DVDs and other materials are checked out at twice the rate
of the national average.

Seriously, Portland is a weirdo place. I can’t tell you how many coffee shop barristas I know who have masters degrees, but decided that they wanted a more mellow life.  One of the coffee shops I frequent regularly is owned by a guy who will sit with me and talk about Foucault, neuroscience, and Quantum game theory (my masters-degree focus).

People here are freakishly well read.  Now I know why: all that “liberal” access to libraries – Oh My!

As my friend, Tony, once said, “In every city, the strippers say they are ‘working their way through college’.  In Portland, it’s true.”

98th Four Stone Hearth – Anthropology Blog Carnival

stone-age-dildo

In this, the 98th Four Stone Hearth, there are a number of cool articles.  But, I think this one takes the cake: Stone Age Dildo Found in Sweden.  Wow …

New Generation Less “Nice”

grand_theft_auto_san_andreas

Found this at the NY Times:

Vindication for crotchety Gen-Xers — already depressed to find themselves the elders in this social relationship — arrived in a paper presented in May at the annual meeting of the Association for Psychological Science in Boston. “Changes in Dispositional Empathy in American College Students Over Time: A Meta-Analysis,” by Sara Konrath, a researcher at the University of Michigan, found that college students today are 40 percent less empathetic than those of 30 years ago, with the numbers plunging primarily after 2000.

As one of those crotchety Gen-Xers myself, I do feel vindicated.

Today’s students scored significantly lower in empathic concern (a 48 percent decrease) and perspective taking (34 percent), considered the more important indices of empathy. In a decisively everyone-for-themselves manner, they are less likely to agree with statements like “I often have tender, concerned feelings for people less fortunate than me” and “I sometimes try to understand my friends better by imagining how things look from their perspective.” This is particularly notable since these are considered shared social ideals: people are more likely to say they agree than they really do.

This is bad news, if it’s true:

The implications are hardly superficial. Low empathy is associated with criminal behavior, violence, sexual offenses, aggression when drunk and other antisocial behaviors. Depressing news. Just don’t expect the next generation to sigh over it, too.

We’ll just have to wait and see if these types of crimes go up, and if we can link them to a general drop in social empathy – no easy task. 

What happened? “We don’t actually know what the causes are at this point,” Dr. Konrath said. But the authors speculate a millennial mixture of video games, social media, reality TV and hyper-competition have left young people self-involved, shallow and unfettered in their individualism and ambition.

I’d blame parents, personally.  These outside factors are not all new.  Hyper-competition was high in the ‘80’s, reality TV has been around in various guises for a while (and bad TV has been on for decades), video games have been around since the ‘70’s, and humans have been prone to idiocy since the dawn of time.

I think, if anything, parents are less involved with their kids.  It’s the same reason kids are fat.  Parents don’t cook healthy meals, they don’t spend enough quality time with their kids, and they don’t know how to say “no” to the kid spending all of his/her time in front of a TV or video game or facebook or their iPhone. 

You can’t blame society at large for your own child’s behavior.  If your kid has empathy problems, that’s your fault.  If you kid is fat, that’s your fault.  It used to be understood by parents that their kids behavior reflected poorly on them.  Now parents think they can blame outside forces – and teachers, principles, and councilors will aid them in that belief. 

If your kid has trouble focusing, it’s ADD.  It’s certainly not that you take them to Starbucks every morning and get them a 700 calorie latte, you never get them to exercise, they are 40 pounds overweight (at 12!!), and they spend all their free time playing Grand Theft Auto.  Nope, it’s the mystical ADD. 

Give me a break.  If this study has any basis in reality, it is a clear indication that the parents of today suck in comparison to the parents a generations ago.  And that is saying something … because our (Generation X’ers) parents were a bit nutty. 

Sociobiology vs Evolutionary Psychology

eo-wilson
In 1975, Edward O. Wilson published a book that has been sending ripples out into the world of human psychology ever since.  His book was largely about the evolved psychology of animals, and only at the last second (in the last chapter) did he talk about humans.  But, it was the last chapter that caused the stir.  In 30 pages, he ripped open a hole that can’t be sown shut.

His book was called Sociobiology and it spawned a movement in the scientific fields of biology and psychology of the same name that took as its central premise that human behavior, like animal behavior, evolved.  It’s a simple idea, intuitive, and (like so many brilliant ideas) obvious in hindsight.  However, it comes as jarring to many.

Early Detractors

From Feminists on the Left, to Christian Conservatives on the Right, people have found this simple idea to go against the belief systems they already had in place, and therefore the idea was scary and had to be stopped. 

Feminists didn’t like the notion that some of how our society is (and certainly was at the time Wilson’s book was published) was “natural” (don’t flip, I’ll deal with that word below).  Christian Conservatives didn’t like it because it was based on evolution (which is wrong, right?) and promoted the ideas of reciprocal altruism, emphasized sexual selection, and linked modern religion with a polytheistic tribal past.

The Left suffers (often) from the Naturalistic Fallacy – confusing the word “is” with “ought”.  It is true that humans can be prone to violence, but that doesn’t mean that they should engage in violence.  Similarly, if it turns out to be true (jury is still out) that human society is prone (by a push from our genetics) to be male “dominated” that doesn’t mean it should be that way, nor does it mean we aren’t allowed to set up social stop-gaps to mitigate those tendencies.  (After all, that is exactly what we do with violence.)

The (far) Right is just off its rocker.  They don’t believe in evolution generally, so there is little hope there.  And even in the cases where they are willing to engage in the argument (starting from the premise that evolution exists, but doesn’t apply to human behavior) their religious feelings still get the better of them. 

Evolutionary Psychology

homer-simpson-brain

Over the last 45 years, Sociobiology has spawned a child: Evolutionary Psychology. 

Where the parent was an umbrella theory that claimed behavior is an evolved trait, the modern child has added multiple premises that make it more vulnerable to attack.

Take this interview with the philosopher of science David Buller whose recent book, Adapting Minds, takes on Evolutionary Psychology directly.

JRM: Why do you say the evolutionary psychology paradigm is problematic?

DB: There are three foundational claims that it makes. One is that the nature of [evolutionary] adaptation is going to create massive modularity in the mind–separate mental organs functionally specialized for separate tasks. Second, that those modules continue to be adapted to a hunter-gatherer way of life. And third, that these modules are universal and define a universal human nature. I think that all three of those claims are deeply problematic.

If anything the evidence indicates that the great cognitive achievement in human evolution was cortical plasticity, which allows for rapidly adaptive changes to the environment, both across evolutionary time and [across] individual lifetimes. Because of that, we’re not quite the Pleistocene relics that Evolutionary Psychology claims. [Regarding universality,] all of the evidence indicates that [behavioral] polymorphisms are much more widespread in all sexually reproducing populations than the idea of a universal human nature would require. So I think the theoretical foundations from which a lot of predictions get made, about what our mate preferences are going to be, or what the psychology of parental care is, are problematic because the theoretical foundation is mistaken.

I agree with Buller, generally.  Evolutionary Psychology has adopted far too many extra hypothesis to be workable in my book.  (And it’s one of the reasons I prefer to call myself a Sociobiologist)  In the modern scientific community the two names – Sociobiology and Evolutionary Psychology – have become synonymous.  That’s a shame.

While some of the early proponents of Sociobiology got overzealous, it remains a simple idea – behavior evolves just like everything else does.  Evolutionary Psychology adds in too much of the “How it Works” into their starting positions.  I think that’s a mistake.  The “how” questions are the hardest and least understood. 

Again, I agree with Buller when he was asked about the value of modern Evolutionary Psychology, he says:

It has led to the asking of questions that needed to be asked, so in that regard I think it’s been a very positive development. Evolutionary theory has not been applied to the study of humans to quite the extent that it should have been to date. I think looking at an emotion like jealousy from an adaptationist standpoint is very positive. It stimulates lines of research that would not have occurred otherwise. But immediately then the paradigm kicks in with its big theoretical apparatus and says, "Oh, well ok, but if jealousy is an adaptation, then differences in the sexes require differences in modules in the sexes." So then you get the whole account of jealousy that’s propounded in the paradigm–the idea that there’s an evolved sex difference, where males are sexually jealous and females are emotionally jealous. So while I think the paradigm has been an extremely positive development on the whole, it has tended to prematurely narrow the kinds of hypotheses that are considered about human evolution.

That is, we shouldn’t throw the baby out with the bath water. 

Modern Evolutionary Psychology may have some big holes in it, but the central premise of Sociobiology is sound.  Ultimately, we are an animal, and like all other animals our behavior is caused by biological processes that include the brain, hormones, neurons firing, etc.  It is only reasonable to suppose that there is an evolutionary basis for our behaviors, even if in the proximate case, it may not seem so obvious. 

JRM: Do you think people tend to resist any evolutionary account of human behavior because it seems to reduce important aspects of our emotional lives–romantic and parental love, for example–to an impersonal desire for reproductive success?

DB: When we introspectively focus on the proximate cause of our behavior, we tend to think it’s sufficient explanation of my getting married that I love this person, and that I have no desire to have children. So the idea that [reproduction] is a complete explanation sets up a resistance in a lot of people [to questions such as] why is it that these emotions have evolved, and what evolutionary function do they serve? That’s actually a different kind of explanation. It’s not an explanation of how proximate mechanisms function, but an explanation of why we have those kinds of proximate causes driving our behavior.

Even an evolutionary biologist like [the late Stephen Jay] Gould was prone to this slippage between proximate and ultimate explanations, and then to rejecting an ultimate explanation because of thinking a particular proximate explanation was sufficient. In Gould’s critique of Evolutionary Psychology, he said, "I don’t think that males are willing to rear babies only because clever females beguile us. A man may feel love for a baby because the infant looks so darling and adorable." Gould was slipping there between the proximate and ultimate explanations. The ultimate explanation is female sexual selection for care-giving males. The proximate explanation has to do with what causes males to respond that way to children, and that can be entirely because they look so adorable. That’s not incompatible with an evolutionary account.

There is such a thing as “human nature” if we use the term loosely.  That is, humans have behaviors, and “human nature” describes the nature of those behaviors – and how they got that way, etc.  But, the reactions people have against such a study comes from the overreaching of some who try to simplify what the term means and turn the term “human nature” into a synonym for “normal” (if we use the word normal to mean anything that is in the majority).  

Being gay is not normal in the sense that it is statistically less likely that someone will be gay than be straight.  But, it is normal for their to be gay people in society.  It is part of human nature for their to be both straight and gay people in certain proportions.  Human nature describes the nature of all human behaviors, not just what is found to be in the majority.  If Sociobiology is the search for human nature – and how it got that way – then it is in this very particular sense of the term.

Modern Evolutionary Psychologists have a tendency to get off track.  Maybe that’s just human nature.  But, if we’re serious about studying why humans act the way that they do, we can’t ignore evolution.