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Our future, our universe, and other weighty topics

Friday, December 22, 2017

He Thinks His Beloved Specks Have Cosmic Implications

Some of the discoveries of scientists are monumental, like the discovery of DNA or the discovery of the cosmic background radiation. But in other cases a scientist may find something tiny and borderline,  but that doubtful little thing may be hyped up to look as if it was something mountain-sized.

An example of such hyping might perhaps be found in a recent announcement about alleged microfossils. The controversial geological specimens were discovered in Western Australia. A UCLA press release tells us matter-of-factly that the “microorganisms” are 3.465 billion years old. The UCLA press release does not mention any controversy about whether these tiny things were microorganisms.

But researching how the story was covered on other news sites, I find there is quite a bit of controversy. For example, an article on LiveScience tells us that “other researchers have cast doubt on whether these sediments house traces of life at all, suggesting that chemical markers thought to represent biological evidence were the result of geothermal activity.” The same article says, “Billions of years of geologic changes leave behind chemical traces in rocks that often resemble signatures of biological remains, according to previous studies.”

A scientist has used some fancy new technique to analyze these geological specimens. Some new gizmo was created to analyze the specimens, but it sounds like possibly unreliable “bleeding edge” technology; the UCLA press release calls it “cutting edge technology.” “It took us 10 years to develop the ability to make these measurements accurately," said one of the scientists.

But Science magazine tells us the following:

[Rasmussen] is concerned that the microfossils may have been badly preserved. Olcott Marshall, who thinks the rock impressions are not fossils at all, but the product of geological processes, is even more critical: “The errors produced by this analytical technique are so large” that the data are not clear enough to say there are different types of microbes in rock, she says.

We learn from the UCLA press release that the scientist making the claim that these microscopic geological specimens are 3.465 billion-year-old and are microfossils is a scientist named J. William Schopf, who has published several papers on these specimens over the course of 25 years, since 1993. He's apparently one of the scientists who spent 10 years working on these little specks. We may wonder whether someone with such a large investment of time in these speck specimens may be biased in his examination of them, more prone to regard them as biological than the evidence warrants.

Schopf's latest conclusions are based on an analysis trying to use radioactive dating to date microscopic specks. The problem with that is while radioactive dating may be reliable when used to determine the age of a skull or a big dinosaur bone, when you try to use radioactive dating on some microscopic specks, radioactive dating isn't terribly reliable – hence the previous quote that “errors produced by this analytical technique are so large.”

The latest work on these alleged microfossils should have been announced with the appropriate caution, with a headline such as “Debate Continues on Whether Australian Microscopic Traces Are Fossils.” But instead our UCLA press release has done the opposite. Not only has the UCLA press release hidden the scientific controversy, but it has announced, most absurdly, that these microscopic traces of an uncertain nature “indicate that life in the universe is common.”

Schopf claims that his research “tells us life had to have begun substantially earlier and it confirms that it was not difficult for primitive life to form and to evolve into more advanced microorganisms.” No, his research tells us no such thing. The age of the earth is believed to be 4.6 billion years old. Finding a microscopic fossil about 3.5 billion years old tells us nothing about how hard or improbable it was for primitive life to form.

Even if it were true that life on Earth arose 100 million years after it first had the opportunity to arise, this would not be a strong reason for thinking that life in the universe is common. Consider this case. You open your new pastry shop one day, and within an hour someone comes in trying to order a pizza. The chance of this happening is very low. You would be mistaken if you reasoned that the chance of such a thing happening must have been high, or else it would not have occurred within the first hour of your shop being open. You are not entitled to draw such conclusions based on the timing of a single occurrence.

The article here states the following by MIT professor Joshua Winn (referring to this scientific paper):

There is a commonly heard argument that life must be common or else it would not have arisen so quickly after the surface of the Earth cooled," Winn said. "This argument seems persuasive on its face, but Spiegel and Turner have shown it doesn't stand up to a rigorous statistical examination — with a sample of only one life-bearing planet, one cannot even get a ballpark estimate of the abundance of life in the universe."

This announcement may end up rather like the “Life on Mars” affair of the 1990's, when some scientists announced with great fanfare that some meteorite that supposedly had come from Mars had evidence that life had existed on Mars. The evidence consisted of marginal specks like the Australian specimens Schopf has studied. In the subsequent years this claim ended up being mainly rejected by other scientists.

 Hyped-up science press releases often are like this

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