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A Slow Day in the Science Newsroom: Much Ado About Algae

When we last checked in with Michael Travisano, a Richard Lenski disciple, and William Ratcliff they were garnering headlines in the New York Times and elsewhere for doing wonderful things with yeast. Carl Zimmer enthused:

Our ancestors were single-celled microbes for about three billion years before they evolved bodies. But in a laboratory at the University of Minnesota, brewer’s yeast cells can evolve primitive bodies in about two weeks.

Writing at ENV, however, Michael Behe entertained doubts about how impressive this really was as a demonstration of Darwinian processes, illustrating how multicellular organisms could have arisen without intelligent guidance ("More Darwinian Degradation: Much Ado About Yeast"):

It seems to me that Richard Lenski, who knows how to get the most publicity out of exceedingly modest laboratory results, has taught his student well. In fact, the results can be regarded as the loss of two pre-existing abilities: 1) the loss of the ability to separate from the mother cell during cell division; and 2) the loss of control of apoptosis.

The authors did not analyze the genetic changes that occurred in the cells, but I strongly suspect that if and when they do, they’ll discover that functioning genes or regulatory regions were broken or degraded. This would be just one more example of evolution by loss of pre-existing systems, at which we already knew that Darwinian processes excel. The apparently insurmountable problem for Darwinism is to build new systems.

Now Ratliff and Travisano are back with more claims to have illuminated the origins of multicellular life. From yeast, the pair have turned their attention to algae. In the lab, they showed how single-cell algae may be transformed into multicellular algae.

Under the headline "Alga takes first evolutionary leap to multicellularity," New Scientist has the story:

A single-celled alga has evolved a crude form of multicellularity in the lab — a configuration it never adopts in nature — giving researchers a chance to replay one of life’s most important evolutionary leaps in real time.

This is the second time researchers have coaxed a single-celled organism into becoming multicellular — two years ago, the same was done with brewers yeast. But the alga is an entirely different organism, and comparing the two could explain how the transition to multicellular life happened a billion years ago.

Permit us to say, once again, we’re somewhat less than blown away by this.

Not only did these scientists fail to explain the origin of true multicellularity, but their results also failed to demonstrate anything substantially new. It has been known for decades that bacteria and fungi and other "unicellular" forms will readily group together in multicellular arrangements (and differentiated cell types within those colonies). James Shapiro at the University of Chicago has a 1988 Scientific American piece titled "Bacteria as Multicellular Organisms" that nicely illustrates this fact with a number of examples.

Recall also that fungi such as baker’s yeast produce an extracellular protein (FLO11) that is hyper-variable, so by applying selection one can easily obtain strains that have different degrees and types of colony organization.

Alas, this is another non-story. It must have been a slow day in the science newsroom.

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Evolution News & Science Today (EN) provides original reporting and analysis about evolution, neuroscience, bioethics, intelligent design and other science-related issues, including breaking news about scientific research. It also covers the impact of science on culture and conflicts over free speech and academic freedom in science. Finally, it fact-checks and critiques media coverage of scientific issues.

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