There almost certainly is life elsewhere in the universe. There is no reason to think that conditions and events that led to life on earth are unique, and the universe is a ridiculously vast place. So the odds strongly favor that there must be many occurrences of life out there. There are interesting sub-questions, however – how common is life, how common is complex life, and how common are technological civilizations? Is the universe teaming with bacteria and fungus and little else, or are the stars buzzing with spacefaring races of every description?

The problem with trying to answer this question is that we have an N of 1 – Earth is the only example of life in the universe that we have. We may find examples of life elsewhere in our own solar system (Mars, Europa, Titan, and Enceladus are the current prime candidates), but that will only give us a tiny bit more data. Life elsewhere in our own solar system (especially Mars) may have been seeded from Earth or vice versa, and so we may find life on Mars but still only have evidence for a single life origin in our solar system.

We may also find multiple independent life origins in our solar system, and that would be extremely cool, but would still only answer one of the three questions above. That would tell us that the origin of some kind of life is likely common, and can occur under a variety of conditions, but would not tell us how common complex life or civilizations are.

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This news is plastered over every general and science news outlet I can find – Italian scientists have been found guilty of manslaughter for failure to properly warn about the 2009 L’Aquila earthquake. They have been sentenced to 6 years in prison and ordered to pay $12 million in damages.  They have two appeals left, and can remain out of prison until they exhaust their appeals.

It is easy to be outraged at a decision that seems so ridiculous on its face. I always try to find the most charitable interpretation of each side of an argument, and so I searched through the news reports for a cogent explanation of this decision. First, it seems the scientists were not convicted for failure to predict the quake, but for how they communicated to the public about the risk of the quake occurring. I could not find a full exact quote of what they did say. The two partial quotes I could find indicate that they said the small tremors that preceded the 6.3 magnitude quake that killed 309 people were “unlikely” to be followed by a large quake. Further, they indicated that small tremors may actually decrease the risk of a larger quake by dissipating energy.

The guilty decision seems to hinge on the fact that many residents were afraid that a large quake was coming and would have evacuated, but were reassured by the risk commission’s statements and decided to stay, leading to their death.

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I don’t have any a-priori or ideological issue with any of the specific practices that fall under the “organic” rubric. I do have a problem with the fact that there is an organic rubric. In fact I think the USDA made a mistake in giving into pressure and creating their organic certification. At the time they tried to make it clear that “certified organic” said absolutely nothing about the product itself, only that certain rules and restrictions were followed in production. It was not an endorsement of organic farming, just a way to regulate the use of the term in labeling food. Unfortunately, it further solidified the organic false dichotomy.

I recently wrote about the Stanford study – a systematic review of studies of organic produce. They concluded:

The published literature lacks strong evidence that organic foods are significantly more nutritious than conventional foods. Consumption of organic foods may reduce exposure to pesticide residues and antibiotic-resistant bacteria.

Some of the reaction to the Stanford study, and my discussion of it, illustrates the problem with the false dichotomy – it encourages muddy thinking. There is a range of practices that are allowed and not allowed in organic farming to meet USDA certification. Excluded practices include genetically modified (GM) ingredients, ionizing radiation, and use of sewer sludge. There is also a long list of allowed and excluded substances (such as organic vs non-organic pesticides).

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Published in Nature this month is a report of the entire genetic sequence of Musa acuminata – the Cavendish banana. The banana is the most popular fruit in the industrialized world. Banana varieties are also an important staple crop in much of the world. The Cavendish, however, is threatened by two fungal infections – Panama disease and black leaf streak disease. Hopefully knowledge gained from the banana genome will lead to new varieties of acuminata that are resistant.

Part of the problem is that the Cavendish is a highly cultivated variety. Starting about 7,000 years ago the banana was cultivated by hybridization of various varieties. Interestingly, most acuminata varieties are triploid, meaning they have three copies of each chromosome, while some are diploid with two copies. Diploid and triploid varieties were hybridized together.

One trait in particular that was selected for was being seedless. Most banana varieties contain numerous large seeds. The Cavendish has none, which makes it an attractive variety as a dessert fruit. However, this also means that there is no longer any sexual recombination within the Cavendish variety. Every Cavendish banana  plant (representing about half of all bananas in the world) is a somaclone derived from the single variety. A somaclone refers to a plant derived ultimately from a single somatic parent cell. This means that every Cavendish banana plant is virtually identical genetically to every other. They are not strictly identical because somaclone variability is possible through spontaneous somatic mutations.  But variation is minimal.

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According to reports, 21 people had to be treated for burns from walking over hot coals at a Tony Robbins inspirational event.

Robbins is a successful self-help guru with a schtick that depends upon the scientific illiteracy of his audience. After a session of telling people how to “unleash the power within” he demonstrates their new-found power by inviting them to walk barefoot over hot burning coals while thinking about cool moss. This is meant to demonstrate the power of mind over matter. This is, of course, nonsense.

The Hot Coal Deception

Many physicists have used the hot coal demonstration to teach a bit of elementary physics, as there is a very simple explanation for how people can walk over hot coals in their bare feet. I have, in fact, heard three (non-exclusive) explanations. The first, and the one that I think is probably the biggest factor, is that wood coals have a very low thermal capacity and conductivity. This means that they do not hold on to a lot of heat energy, and they conduct that energy very slowly. Therefore little heat is transferred to the soles of the feet – if you walk briskly across them and give little time for heat transfer.

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One of the themes of this blog is the misreporting of science information in the lay media, so I am always interested in a particularly bad piece of science reporting. Several readers pointed me toward this piece in The Telegraph about studying genetic ancestry. I know newspaper writers usually don’t write their own headlines, but in this case the headline is partly a quote from the article itself: “Scottish lecturer found to be ‘grandfather of everyone in Britain.’”

That is a misleading and useless characterization of the science story covered in the article. The phrase “grandfather of everyone in Britain” does appear as a quote from “scientists”, although no specific name is given. I know from personal experience and talking to other scientists who have been misquoted by the media that the presence of quotation marks does not mean that a real scientist actually uttered those words. It is possible that they did, however. Typically a reporter will interview an expert for thirty minutes or more about the topic of their report, and then use only small bits from the interview, or perhaps none at all. Good journalists will use the expert to help them understand the topic and shape the article they are writing. However, too often journalists (especially those who are not specifically trained as science journalists) will just fish for provocative quotes they can weave into the article they have already mostly written. Even worse, they may put quotes into the mouths of their experts. “Would you say that…”

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The history of governments meddling in the practice of science is not a good one. The most infamous case is that of Lysenkoism -Stalin backed the ideas of Trofim Denisovich Lysenko who believed in the inheritance of acquired characteristics. His ideas became of the official sanctioned science of the Soviet government. Genetics was declared a “bourgeois science,” or “fascist science,” and many geneticists who disagreed with Lysenko were executed or sent to labor camps. Execution tends to have a chilling effect on the free exchange of ideas and the practice of science. Over seven decades later genetic science in Russia is still lagging behind.

In the US we have a similar problem – not the Gulag, but political factions that disagree with certain findings of science that are ideologically inconvenient for them. The two biggest issues being targeted (but certainly not the only ones) are evolution and climate change. Much of the focus has been on what should be taught to students in science class (my vote is for science).

Recently the North Carolina legislature proposed House Bill 819 to study the effect of climate change on sea levels, and therefore coastlines. For some reason the legislators felt the need to include in the bill specific restrictions on how the science can be done. Section 2 includes this line:

These rates shall only be determined using historical data, and these data shall be limited to the time period following the year 1900. Rates of sea-level rise may be extrapolated linearly to estimate future rates of rise but shall not include scenarios of accelerated rates of sea-level rise.

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Pigeons have an uncanny ability to navigate accurately over long distances. This has been clearly established and exploited for centuries. Yet scientists are still uncertain about the underlying biological basis for this ability. There are four basic mechanisms that pigeons appear to use in returning to their home loft from an unfamiliar location. They use the position of the sun, the magnetic field of the earth, visual cues, and the dispersal of odors in the environment.

Pigeons, therefore, may get a general direction and orientation so that they know which direction to head in. Once they get to familiar territory they then can use visual and olfactory information to zero in on their home. There has been robust research and at times fierce debate about all of these mechanisms. The one that seems to get the most attention in the press is the orientation to the earth’s magnetic field, which is the subject of a new interesting study.

Researchers looking at the brains of pigeons have found 53 neurons that appear to fire in response to the presence, strength, and orientation of an external magnetic field. If true this would point to an important component of the pigeons “gps” system for sensing not only their directional orientation, but perhaps even their general location. The neurons also seemed to have a maximal response to the approximate field strength of the earth’s magnetic field.

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Earlier this week I wrote about paradoxes in science, about how they are good things pointing the way toward new research and possibilities. Science deniers, however, exploit them to cast doubt on established science, without creating a viable scientific theory of their own. I gave as an example the solar neutrino problem – the fact that in the 1980s and 1990s neutrino detectors were detecting 1/3 to 1/2 the solar neutrinos than the standard model of particle physics predicted. Creationists used this to argue that the entire nuclear fusion model of stars was wrong.  It wasn’t long, however, before the missing neutrinos were discovered and the paradox resolved.

Recently I was asked about another sun-based paradox that creationists use to argue for a young earth – the faint young sun paradox. This was first pointed out by Carl Sagan and George Mullen.  Our models of stellar evolution indicate that the sun has been getting steadily brighter and hotter over the last four billion years. As hydrogen is fused into helium and helium therefore builds up on the core of the sun, it has to burn a little hotter in order to maintain equilibrium. The sun is burning about 30% hotter today than it was four billion years ago.

The sun is the major source of heat for the earth’s surface, and therefore a colder sun in the past would mean that the earth was colder, by about 25 °C.  By this factor alone the earth should have been mostly a ball of ice and snow up until 1-2 billion years ago. However the geological evidence points strongly to there being liquid water on the earth even when it was young.

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Paradoxes exist in science for a very good reason. Science is a human-wide effort to understand how the universe works. When functioning properly it is therefore transparent and open. Further, science is describing one reality, and therefore all of the various scientific models for how bits of the universe work must all be compatible with each other. Science needs to all mesh into one big model of reality. Science also follows rules of evidence, logic, and cause and effect. You cannot invoke magic or arbitrarily suspend laws of physics as needed.

When one bit of evidence or scientific model contradicts another (they both cannot be correct at the same time) we have a scientific paradox. Since our models of reality are incomplete (and arguably always will be) scientific paradoxes pop up all the time.

How one responds to a scientific paradox reveals a great deal about how they approach science and knowledge. Those who crave certainty are made uncomfortable by paradoxes because they point to uncertainty. To a scientist, however, paradoxes are nothing less than awesome, the holy grail, the best thing since sliced bread. To a scientist an apparent paradox (really all scientific paradoxes are temporarily “apparent”) is a bright neon sign proclaiming, “This way for discovery!”

Paradoxes do not exist in reality, only in our current models of reality, and so they point the way to flaws in our current models. They therefore also point the way to further research to improve those models, fix errors, or fill in missing pieces. In short, scientists love paradoxes.

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