Monday, June 27, 2016

Metals in Biology

For any regular readers, I'm sorry to have missed posting last week. I was knocked offline by my computer spraying sparks (from a failed video card). After some troubleshooting, I determined that increasing amounts of sparks would be generated each time I applied supplementary power to the video card. So, now I have a nice and new video card and can once again do computery things.

Even though such things seem to be more in the realm of science-fiction than biology, I really like the idea of metals being used in biological systems. Specifically, metals being used for their structural characteristics, not simply as ions in protein complexes (hemoglobin, chlorophyll, cytochromes, etc.).

If the sauropod dinosaurs had built their bones from steel, they might have been able to grow far larger than they did. If turtles grew iron into their shells, they would be protected from even the most determined of [existing] predators. Organisms with metal threads through their skin might be able to perceive and/or generate radio waves. Essentially anything our technology uses metals for would potentially be within the realm of evolutionary biology (since it all comes down to physics in the end). The world would be a very different place.

It turns out that some organisms actually do grow metal in specialized tissues. Well, not exactly metal, usually, but more like heavily metal-reinforced tissues.
Metal-infused tissues have appeared sporadically in a range of lineages. In every example I've been able to find, the tissues are directly involved in predation or defense. The ever-present biological arms-race between predator and prey has drove the evolution of advanced [metal] weaponry and armor. Maybe one of the lineages will adapt to use metal more generally and evolve into a space-living creature that can migrate to other star systems and thus survive the death of our sun. Maybe I should read less science-fiction before bed-time.