Blessed are the oysters

It is a common fallacy in biology that human kind is the pinnacle of evolution. Mostly this is because as humans, we are both smart and vain. We are smart enough to figure out where we come from (56% of redneck America notwithstanding), and vain enough to believe that this must make us special. But what does it mean to be evolutionarily advanced?

One approach is to look for the tried and true. The less a gene changes, the more superior it must be over any possible alternative that might arise throughout the depths of time. In fact, one could argue that the more something changes, the less evolutionary fitness it possesses. By this argument, the most advanced creatures on earth are not the most different, they are the most simple. So the most evolved creatures on Earth are the Archaea, those primitive, bacteria-like creatures that have been living in hot springs, unchanged, for as long as we have rocks for. These creatures are so advanced that any random mutation makes them less fit than their parent, so they remained genetically static through the entire evolution of multicellular life.

However, the existence of other, more recent forms does tend to suggest that the tried and true is not the only possibility. After all, one of the reasons Archaea are only found in extreme environments is that they get turned into lunch everywhere else. So what other quality could we use to determine the most advanced life form. Most new genes? Dunno how we stack up there, but I doubt we can hold a finger to the conifers, which have single chromosomes that are larger than many creatures’ entire genomes.

Of course, plants are notorious for doubling and quadrupling their genome at the drop of a (pine) needle. The red spruce genome has more repetition than a primary school arithmetic lesson. So perhaps instead of the most genes, it should be the highest number of different genes. But determining that could be rather difficult, considering that each year only a handful of species have their genomes sequenced, while hundreds of new species are discovered.

For this reason, looking at actual genes themselves is a fairly impractical task. After all, natural selection doesn’t work directly on genes anyway. It works on the chemicals and mechanisms for which they code.

This is where the whole idea of human intelligence as the epitome of evolution comes from. Intelligence is not a gene, it the expression of a (or more likely, many) genes.

This is a more interesting argument for the rest of us non-geneticists anyway, since we appreciate eyes and wings and brains more than interminable strings of the same four letters.

It also makes it easier for us to stroke our own egos. After all, we only need to show that the evolution of intelligence is the largest and most unique step ever taken in the history of evolution in order to crown ourselves as the cream-du-jour of this process.

Unfortunately, this may not be so easy. While vertebrate evolution has shown a tendency towards larger and more complicated brains, we are not, pardon the pun, the only fish in the sea. Back when our phyla was just a twinkle in a segmented worm’s eye, other creatures with brains far more developed than our forbearers were taking the Palaeozoic oceans by storm.

I am talking, of course, about the molluscs. The most intelligent creatures alive today outside the vertebrate kingdom are the free-swimming, many tentacled molluscs known as cephalopods. In fact, some of the octopi currently on display the world’s aquariums are actually smarter than the toddlers who come to gawk at them.

But cephalopods are not the most successful molluscs. They are third.

Starting in the late Cambrian, and continuing until the event that wiped out the dinosaurs, cephalopods were doing pretty well. For a time, way back when men were men, graptolites were graptolites, and continents were bare and devoid of multicellular life, they were the most complex and dangerous creatures on the planet. However, they were not the most numerous, or widespread. The molluscs that out-diversified them, gastropods and bivalves, lost their big brains, their free swimming ways, and their manipulative tentacles. Most of them became scavengers or filter feeders. This change to simplicity allowed them to colonize fresh water, and even land. In the process, some of them lost the mobility, the eyesight, even the prehensile manipulators that made their ancestors so complex. So from this point of view, the most evolved mollusc alive today is not the intelligent, free-swimming, predatory nautilus. It is the brainless, sessile, omnivorous oyster.

Is this our future? To evolve from mobile, free thinking predators to sessile filter feeders? It may seem unlikely, but consider that in the last 200 years, hunting and gathering societies have become all but extinct. And what have we invented to fill the time once occupied by devising plans to kill creatures faster and stronger than ourselves?

Oh, sure, some of us have composed symphonies, built cathedrals, and gone to the moon. But have you? I can count the number of men who have been to the moon on both of my six-fingered hands. And the last of these men left the dusty lunar surface before I was born.

No, to judge the true aspirations of mankind, we need to look a little closer. We need to look at ourselves. We need to look at a selection of inventions that all of us have used, and that some of us may be using right now.

I nominate three: The couch, the pizza delivery truck, and the television remote control. We are no longer intelligent, free-ranging, pretatory primates. Brainless, sessile, omnivorous primates are what we have become. It is my prediction that in 300 million years, hyper-intelligent beetles will be harvesting our progeny for pearls.

Of course, pizza on the couch is not the best possible position to be in, it is simply the one most easily obtained on a Friday night. With a little effort, we could evolve our way towards greater comfort. Instead of pizza, it could be nectar and ambrosia, those divine foods of the primordial gods. Instead of the delivery truck, we could have shapely handmaidens of an attractive, fertile phenotype. Instead of the couch, it could be the Jacuzzi. Or a hot spring. The Archaea have known this all along, which is why they have not left their bubbling spas for several billion years. Ladies and gentleworms, we have a winner.

Say a prayer for Todd and Brant

On April 25, a small earthquake in northern Tasmania caused a mine collapse in the Beaconsfield Gold mine. One miner was killed, and two others were reported missing.

Last Sunday, 5 days after the accident, the two missing miners, Todd Russell and Brant Webb, were found to be alive, having been protected by the safety cage of their mining equipment. By yesterday, rescuers were able to drill a 4 inch hole to the cavity where these men are trapped, through which they could pass water, food, and supplies.

The good news is that both men are in fairly good health and spirits. The accident occurred 925 meters (3035 feet) below the surface, so hypothermia is not an issue due to geothermal heat. And at least one miner asked that his supplies include a weekend paper, so that he could look for a new job.

The bad news is that the rockfall in which they are trapped is quite unstable, so that the rescue team thinks that it will be at least three more days before they can drill a hole large enough to evacuate the men. So here’s hoping that they hang in there, and that no complications occur.

A geologic overview of the orebody can be found here:
http://leme.anu.edu.au/RegExpOre/Beaconsfield.pdf (pdf file)

News updates available via the ABC, and all major Australian news media

Sensitivity vs. Stability

As a result of some really sloppy behavior on the part of our instrument yesterday, we tore the whole front end apart, put it back together, and then tuned it back up from first principles. It was a kick-ass learning experience, even if it did take all morning, because when we tuned it back up, we tuned for stability instead of sensitivity. I haven’t actually done that before.

Sensitivity is all the rage these days. You’d think that the geological community’s ICP-MS scientists were a bunch of SNAGS at a speed dating festival, the way they constantly go on and on about their sensitivity, counts per ppm and limits of detection. But stability is also important. Especially in certain contexts.

Yesterday, for example, we were measuring lithophiles in basalt. This sort of measurement doesn’t require sensitivity- any triple-thumbed numbnuts could detect them. In fact, the dilution factor is generally increased to prevent excess detector wear. The errors on the elemental ratios are not count-rate limited; they are limited by the drift in relative sensitivity for the various elements. So we managed to address that really well, and everybody went home happy on Friday afternoon.

Say "hello" to my little friends

Who would have thought that a few simple filaments of hydrated mantle could add so much complication to a home renovation? First person to correctly identify these minerals wins a rodent-sized isolation suit. I'll post more details once I get some sleep.
-LL

Tear down the walls.

My wife and I tore out our kitchen today, Good Friday. If we are lucky, a new kitchen will rise from the grave on Sunday. However, the timescale of this sort of miracle is sufficiently long that I suspect we will have to wait for the contractors. And pay them.

Clean insulators are a man’s best friend

Like all ICP mass spectrometers, our machine spews a lot of ionized gunk into the extraction lens and first lens stack, so after a couple of weeks of operation, these tend to get a little bit grimy. Usually this is no big deal. We swap in the clean sets, clean the dirty ones, and continue on our merry way. But halfway through last month, this technique stopped working.

The clean set of lenses was running at bizarre voltages, and the sensitivity was rather ordinary. So, we cleaned them again, but to no avail. In fact, we ended up purposely running the old, dirty set while we tried to figure out why the clean lenses were not working.

It turns out that taking the gunk off the lenses was necessary, but not sufficient, to restore the machine to its usual happy state. The insulators also had to be replaced, since they had gunked up as well.

So, dirty lens gunk seems to have the bizarre quality that it is insulative enough to build up a static charge sufficient to deflect the beam, but conductive enough to let voltage leak off the lenses. It just takes insulators a lot longer to gunk up to the point where they stop functioning properly, so we can get out of the habit of checking them. This just goes to prove that Murphy’s Law applies to dirt.

I have no idea what this gunk actually is. Most of the material that gets aspirated into the mass spectrometer is argon, which is well known for its reluctance to take solid forms. I suppose that if I really wanted to know what it was, I could just whack a spare dirty lens in the machine and blast away at the gunk deposits. But that would damage the lens more than the gunk does, since craters aren’t easily removed with a bit of polishing compound and some elbow grease.

Besides, it doesn’t really matter what it is, as long as we can prevent it from building up to the point where the machine stops working. It’s not like that knowledge would allow us to scrub less vigorously in order to remove it. So that question, for now, will continue to remain unknown.

Why I became a geologist

Occasionally, I have to do a little science to remind my boss why he pays me. The science I do is geology. It’s a good science- all about the science, not the egos or the cult of personality. Disciplines like physics or biology are filled with great men, and lofty ideas. Earth science is not lofty. Not even when dealing with atmospheres. We don’t go for lofty. We go for interesting, pretty, or cool.

Geology doesn’t have great men, either. There are historically important geologists. But they are men that only other geologists have heard of. And some of them, like Inge Lehmann and Mary Anning, are not actually men at all.

This is not to say that the great men of other disciplines haven’t had any impact on geology. Charles Darwin made important observations in the field of igneous petrology, and Ernest Rutherford was involved in some of the earliest geochronology attempts. But the practice of geology requires a certain amount of perspective; this tends to put the egotists and their self-importance in their properly insignificant place. Everyone in Earth science knows that, no matter how grand their theories or widely applicable their methods, Mother Earth is smarter than they are. Lest we forget, there is always the story of Lord Kelvin to remind us of the dangers of brash predictions.

Lord Kelvin is, of course, the big man of 19th century physics and thermodynamics. He was smart, he was proud, he was arrogant, and he decided that he would use his mighty intellect to determine the age of the earth. So, he measured and calculated, deduced and deducted, and came up with an age of 100 million years.

All the mud-digging, fossil picking geologists scratched their heads and said, “Look, buddy. No disrespect or nuthin’, but that number seems to be a bit on the small side. You know, `no vestige of a beginning, no prospect of an end’?” But Lord Kelvin would have none of it. He did the calculations, he did the maths, he solved the fundamental physics, and it was simply beyond rational comprehension that he could be wrong.

Only he was. Kelvin’s age was too young. 4,460 million years too young. Even the sedimentary rocks that underlie most of England are generally older than his estimate. Because, while he thought he had all the answers, the reality was that he didn’t know as much as he thought he did. And the unknown kicked his ass.

In geology, arrogance isn’t just an obnoxious personal trait. It is a professional hazard, and those who practice it invariably end up making themselves look monumentally stupid, on scales that boggle the mind. That is the main reason I like this profession.

The other, minor reasons are almost inconsequential. Obviously I don’t mind the fact that major meetings serve free beer at morning and afternoon tea. Sure, it’s great, but that is a minor perk, really. I could do better by tending bar for a living.

Geology also often involves a lot of travel. I don’t mind travelling. In fact, I rather enjoy it. But was this a major factor in my professional career? Absolutely not. In fact, I vehemently deny any suggestions that such a base motivation as tourism influenced my choice of an Australian PhD, with field work in Brazil. The meetings in Sydney, Cape Town, and Washington DC were a chore, not a perk. It was tough, serious science, and this is demonstrated by my forthcoming papers, “Porites point break: the impact of intensive surfing on the coral reef ecosystem”, and “The variable effect of sunscreen accumulation on cosmogenic nuclide production in beach sands: Gold Coast vs. Copa Cabana.”

Fire and Ice

Some say the world will end in fire;
Some say in ice.*

Tomorrow we have a total fire ban declared for 24 hours starting at midnight tonight. We also have snow flurries predicted for areas above 1400 meters. I’ve lived in Canberra for over nine years now, but at no time have we had fire and snow forecast for the same day. Gotta love the local climate…

*Some Yank poet