Biological complexity: bacteria 'see' light (Introduction)

by David Turell , Wednesday, February 10, 2016, 15:25 (3209 days ago) @ David Turell

It is known that bacteria can respond to light. An understanding of that mechanism has appeared:-http://www.the-scientist.com/?articles.view/articleNo/45296/title/Sighted-Microbes/-"A cyanobacterial cell acts like an eye, refracting light onto the cell membrane in a similar way to how the lens of a human eye refracts light onto the retina, according to a study published yesterday -***-"The fact that bacteria respond to light is one of the oldest scientific observations of their behaviour,” said study coauthor Conrad Mullineaux of Queen Mary University of London in a press release. “Our observation that bacteria are optical objects is pretty obvious with hindsight, but we never thought of it until we saw it. -***-"Mullineaux and colleagues showed that a cyanobacterium, about half a billion times smaller than the human eye, refracts light onto the opposite side of the cell from the point of incidence. The focusing of light on photoreceptors in the cytoplasmic membrane then triggers the cyanobacterium to move in the opposite direction—i.e., toward the light source.-“'We noticed it accidentally,” Mullineaux told BBC News. “We suddenly saw these focused bright spots and we thought, ‘bloody hell!' Immediately, it was pretty obvious what was going on.”-"Gáspár Jékely of the Max Planck Institute for Developmental Biology in Germany told BBC News that the study offered an “elegant demonstration” of the mechanism for phototaxis in these bacteria. “Cyanobacteria are 2.7 billion years old, so it's much older than any animal eye,” he said. “Presumably, this mechanism has existed for a very long time.'”-Comment: It is as if a light-sensing structure was put in place long before evolution got to making camera eyes. Structural preparation for the future as Denton would view it. Structure first, function second. Gould also understood this, I have found in my reading.