Science – Page 68 – a sibilant intake of breath

Evolution and ‘Darwinism’

In the New York Times, Carl Safina has written an essay arguing that the common conflation of evolution with the work of Charles Darwin is deeply damaging: Darwinism Must Die So That Evolution May Live. There is certainly a good case to be made here. While Darwin’s insights were profound and highly significant, he knew nothing about DNA, patterns of heredity, or the mechanisms of microbiology. Furthermore, it is problematic to associate the work of one person with an entire scientific discipline. As the essay asserts: “We don’t call astronomy Copernicism, nor gravity Newtonism.”

Overall, I agree that the link between Darwin and contemporary evolutionary science ought to be softened. We can recognize the genius of Newton without asserting that his ideas are the be-all and end-all of physics, or optics, or whatever.

At this point in the history of science, we should recognize that evolution has progressed far beyond Darwin. In some cases, his insights have been deepened and expanded through the emergence of new knowledge. In other cases, misconceptions of his have been successfully challenged. The fact of evolution is widely recognized as one of the most important elements for understanding our world – that status is justified regardless of the individuals who most visibly brought the fact to our attention.

The MMR vaccine and autism

I am glad to see that an American court has rejected allegations that the MMR vaccine causes autism. The anti-vaccine movement that is gaining ground in Europe and North America is a worrying one. It is worrying on a direct level because it exposes children to new dangers and raises the risk that diseases that have been all but eradicated will return. It is also worrying insofar as it demonstrates the depth of the lack of trust between large elements of the population and doctors and scientists.

As with the alternative medicine craze, a disturbing number of people have decided that evidence-based medicine is lacking and have opted for alternatives that range from relatively harmless quackery to dangerous malpractice. It leaves one wondering if there is any mechanism through which broad public confidence could be restored.

Avocado trivia

XUP’s blog has a surprising and entertaining compendium of facts about avocados. My favourite among them is the fact that all the animals native to the Americas and large enough to pass avocado pits through their digestive tracts are now extinct – among them, the giant sloths that were of such interest to Thomas Jefferson.

I have generally found avocado tastiest when incorporated into the right kind of sandwiches.

Video on the history of the Earth

Seed Magazine has a neat video up, in celebration of Charles Darwin’s 200th birthday. It condenses the 4.6 billion year history of the Earth into one minute of footage. As such, it gives one a sense of perspective, in terms of how little of the history of life humanity has witnessed.

One quibble: the video refers to photosynthesis by ‘blue-green algae,’ which is a misnomer. So-called ‘blue-green algae’ aren’t algae at all; they aren’t even plants. They are cyanobacteria.

OxBridge and the future

The two books I am reading most actively right now both make me miss Oxford. They also make me regret the fact that I am not out traveling or working somewhere exciting.

The first book is Simon Winchester’s The Man Who Loved China: The fantastic story of the eccentric scientist who unlocked the mysteries of the Middle Kingdom. I have read several of his books before: one on the Mercator projection, and another on the genesis of the Oxford English Dictionary. While I am only halfway through this latest book, I think it is better than Mercator but worse than OED, though that probably reflects my own interests as much as anything else. In any case, the book conveys a wonderful sense of what was possible for a motivated and intelligent individual in the position of its protagonist: Noel Joseph Terence Montgomery Needham.

The second book is Oliver Morton’s Eating the Sun: How Plants Power the Planet. Evidently, it is largely a study of the nature and history of photosynthesis. The book contains a good summary of early climatic science, with engaging and informative asides on nuclear physics, biochemistry, and much else. It also includes a great many references to life in Cambridge, during the period between the early outbreak and late aftermath of the second world war. It is a period of unusual interest for climatologists, for reasons I described in my barely-remembered thesis. Personally, my impressions of Cambridge are dominated by the music video to Pink Floyd’s “High Hopes” – one of the very few music videos I have ever watched, and one of the handful I have enjoyed.

What they brought to the forefront is that it is possible to be out and doing interesting things (though certainly more challenging if you mean to do it in a low-carbon way). I would certainly be strongly tempted to strike away from Ottawa to more interesting places, once societal dues have been paid. Where or what that would involve, I cannot yet guess.

Physics and the size of creatures

A book I am reading made reference to an interesting essay from 1928 that I thought I would share. It is about the basic physics of plant and animal pyshiology, as it relates to the size of creatures. It was written by J. B. S. Haldane and is entitled: “On Being the Right Size.” Along with discussing matters like bone strength, gravity, surface tension, and breathing, it features some unusually clear and poignant imagery:

You can drop a mouse down a thousand-yard mine shaft; and, on arriving at the bottom, it gets a slight shock and walks away, provided that the ground is fairly soft. A rat is killed, a man is broken, a horse splashes.

In short, it is an interesting thing to read and contains many facts and observations that are useful to know.

Many of the issues raised in this essay re-appear in Insultingly Stupid Movie Physics explanation of scaling problems in films.

The oil sands, coal, and new regulations

The sheer determination of Canada’s current government to protect the oil sands by undermining Obama’s climate policy is considerable. Most recently, they have been arguing that oil sands extraction operations should be treated in the same way as American coal plants, and thus partially or fully protected from expensive new regulations.

For one thing, an ideal climate policy would drive the rapid replacement of existing coal plants with renewable sources of energy. For another, coal plants that were given free credits in some kind of ‘grandfathering’ system would be pre-existing facilities, built before climate concerns were as acute as they are now. A decent climate policy absolutely needs to prevent the construction of new coal power plants. If someone demonstrates safe, effective, and economical carbon capture and storage, that requirement may relax somewhat but, for the moment, we cannot assume that coal has a place in our next-generation energy mix.

Given the ambitious plans for expansion, the oil sands are much more like new coal plants than like old ones. As such, they should face the same tough rules as new facilities. Special exemptions may serve the short-term interests of some individuals and companies, but allowing the oil sands to develop along their present course is very much against the long-term interests of Canadians.

NASA’s Orbiting Carbon Observatory

Later this month, NASA will be launching the Orbiting Carbon Observatory (OCO): the first satellite designed to make precise measurements of carbon dioxide release and absorption around the world. This should provide important new information about how carbon dioxide is being emitted from human activities and degraded sources (such as decaying forests), as well as the operation of those natural sinks that continue to absorb atmospheric carbon dioxide.

The OCO will work using three parallel high-resolution spectrometers, being fed light by a common telescope. They will simultaneously measure concentrations of CO2 and molecular oxygen.

The new satellite will be placed at the front of a string of satellites in the same orbit: the Earth Observing System Afternoon Constellation, known more informally as the A-train. By having the satellites all look at the same areas in quick succession, the data from their various instruments can be assembled into a single high-quality, three-dimensional dataset. Five satellites are already in orbit, with two planned, including the OCO.

If all goes well, the OCO should be in orbit on February 24th.

[Update: 24 February 2009] It seems the launch has failed and the satellite has been destroyed. This is very disappointing: a blow to climate science, and to our chances of avoiding dangerous climate change. Hopefully, NASA will rebuild the satellite and try launching it again.

That would be a much better expenditure of resources than adding to the ISS or flying shuttles.

Climate change and salt water infiltration

In addition to the direct effects of climate change induced sea level rise, it is important to be aware of the effect of salt infiltration on farming. Much of the world’s cropland is near the coast and at low altitude. It is therefore vulnerable to being rendered infertile by salt from the oceans, as increased sea levels produce brackish rivers and more extreme storm surges. Many of these croplands are in developing countries, where the compounded effects of climate change are most likely to overwhelm domestic adaptation capacity.

Scientists have predicted that a 90cm increase in sea level would cause major infiltration problems in Bangladesh. Most recent scientific evidence suggests a sea level rise of about 1m by 2100, and possibly significantly more.

Global glacier index

This winter has involved a lot of debate on climate changed based around anecdotes: ‘it is snowing in England, therefore it isn’t happening’ or ‘there are terrible fires in Austalia so it is.’ In the end, while anecdotes can provide the imagery that motivates people to act, it is only through the analysis of large amounts of data that high quality conclusions can be reached.

On that front, the global glacier index update on RealClimate is a good example. They examine data on the mass balances of glaciers around the world between 1980 and present, revealing a very clear trend. Similar statistical analysis is performed on the terminus behaviour of the glaciers.

Human beings have a tendency to place undue weight on things we happened to personally observe recently. It’s part of a set of heuristics that aids our functioning in some circumstances, but it does us a great disservice when we are contemplating phenomena that are exterior to our normal modes of operation.