Earth Alien Discovery Under Attack

The news was that researchers had discovered a form of life in a California lake that is able to live off arsenic. Although arsenic is typically poisonous to life, it is similar to an element crucial for life—phosphorus. For that reason, scientists had long speculated that some life-forms, whether on earth or elsewhere, might be able to live off arsenic in lieu of phosphorus.

Some life-forms might be able to live off arsenic in lieu of phosphorus.

While some of the researchers’ conclusions about the arsenic-consuming bacteria remain, other, more dramatic conclusions have been challenged by other scientists. For instance, the claim that the bacteria were able to use arsenic as part of their DNA was called into question, as was the claim that the bacteria were subsisting entirely on arsenic.

The challengers note that the growth medium for the bacteria may have been contaminated with just enough phosphorus to keep the bacteria alive, giving the false impression that the bacteria were living on arsenic. Further, perhaps arsenic was only “stuck to” the outside of the bacterial DNA, rather than serving as a functional part of the genome.

The original researchers have stuck by their work, pointing out, among other things, that even if the growth medium had been contaminated by phosphorus, it would have been an amount insufficient to allow the bacteria to grow as they did. Nevertheless, a reader points us to one scientist’s blog entry concerning the study. The entry—some of which the scientist has transformed into a letter to the journal Science—concludes, “I don’t know whether the authors are just bad scientists or whether they’re unscrupulously pushing NASA’s ‘There’s life in outer space!’ agenda.”

We’ll let that sink in without further comment!