Biological complexity: more bacterial mat complexity (Introduction)

by David Turell , Thursday, January 06, 2022, 18:03 (1052 days ago) @ David Turell

New layers defined:

https://www.newscientist.com/article/2303605-bacteria-form-complex-structures-like-thos...

"Biofilms, slimy clumps of microorganisms like bacteria and fungi, were long thought to be biologically simple, with no more than a primitive level of structural organisation. This contrasts with many multicellular organisms, including animals, in which cells can grow into different forms at different times and places during the body’s development to produce complex and varied biological structures.

"Now, Gürol Süel at the University of California, San Diego, and his colleagues have discovered that bacterial biofilms are less simple than we had thought. The researchers found that the biofilms form ring-like structures as they grow and consume the nutrients in their environment. As the nutrient supply diminishes, certain cells essentially become frozen in time in terms of the way they function, as a wave of nutrient depletion washes over them. This is known as a “clock and wavefront”, and has previously been seen only in animals and plants.

“'If we just think of [biofilms] as globs of bacterial cells, even if they’re from one species, we’re mistaken,” says Süel. “They’re highly organised, and they’re organised in a very non-trivial way. This organisation seems to be reminiscent of what vertebrates and plants did during development, so there must be a connection there.”

"Though the research was focused only on observing the patterns, Süel proposes that the patterning could be the biofilm diversifying its resilient cells to try to increase its chances of survival.

"While biofilms have been shown to be more complicated in recent years, being capable of forms of memory and long-distance communication, the discovery of complex structures could challenge the assumed divide between simple, unicellular organisms and complex, multicellular ones.

“'That debate will be rekindled by this study,” says Tanmay Bharat at the University of Oxford. “From an evolutionary cell biology perspective, it would be interesting to study where the differences lie. What defines a true multicellular organism?'”

Comment: As usual I have to reinterpret this in ID terms. The designer preplans for the next stage in complexity and a giant step was multicellularity with sexual reproduction.