July 19, 2015 | David F. Coppedge

Tiny Organisms Control the World

An unexpected source that regulates global climate is found among the smallest of living things.

In a piece entitled, “Sea Creatures Make Brighter Clouds to Cool the Earth,” Live Science reports on research out of the University of Washington on the role of plankton in cloud formation, a major regulator of the climate.

Marine phytoplankton, which are tiny organisms that rely on light to grow and spread into globs in the ocean, influence how clouds accumulate droplets. Researchers found that the number of droplets over the Southern Ocean nearly doubles during summer months because the sun-loving plankton are more abundant then. Clouds with more droplets are brighter and able to reflect more sunlight, preventing solar radiation from reaching Earth, the scientists said.

The reflection of these droplets prevents excessive heating of the atmosphere. Although particles from volcanoes and industrial smoke can also form condensation nuclei for clouds, the waste products of marine algae fluctuate through the year, providing more bright droplets for clouds when they are needed most for cooling.

Phytoplankton — the tiny, green algae at the surface of the ocean — produce airborne gases and organic matter that form marine aerosols. During the summer, when phytoplankton take advantage of the extra sunlight to proliferate, the wind picks up water and releases it into the atmosphere as sea spray. This enriched salty water enhances the ability of the sea spray aerosols to attract water droplets that eventually condense into cloud droplets, [Daniel] McCoy said.

The Invisible Jewels

Speaking of small marine organisms, the light & magic show of tiny copepods (crustaceans) known as “sea sapphires” (3/03/14) has been partly explained. PhysOrg revealed the secrets in “The secret to the sea sapphire’s colors—and invisibility” from work at the Weizmann Institute.

Sapphirina, or sea sapphire, has been called “the most beautiful animal you’ve never seen,” and it could be one of the most magical. Some of the tiny, little-known copepods appear to flash in and out of brilliantly colored blue, violet or red existence. Now scientists are figuring out the trick to their hues and their invisibility. The findings appear in the Journal of the American Chemical Society and could inspire the next generation of optical technologies.

The invisibility trick appears to come from these animals’ ability to shift the wavelength of their intensified reflections into the ultraviolet. Will invisibility cloaks for humans be coming down the line?

The researchers measured the light reflectance—which determines color—of live Sapphirina males and the spacing between crystal layers. They found that changes of reflectance depended on the thickness of the spacing. And for at least one particular species, when light hits an animal at a 45-degree angle, reflectance shifts out of the visible light range and into the ultraviolet, and it practically disappears. Their results could help inform the design of artificial photonic crystal structures, which have many potential uses in reflective coatings, optical mirrors and optical displays.

As crustaceans, these marine animals possess compound eyes, a mouth and gut, an excretory system, swimming appendages and sensory antennae. Only the males produce the brilliant colors and perform the invisibility trick.

Evolutionary theory provided neither a foundation or added value to these amazing stories.  One can imagine them trying.  Let’s imagine; clouds were rare or absent in the early earth atmosphere, so the heat caused more mutations in simple microbes. These mutations tweaked membranes to become chloroplasts. More mutations in the chloroplasts developed into photosystems I and II with the ability to harvest light with quantum-mechanical efficiency, all by mistake. The lucky mistake cooled the atmosphere, so that trillions of other mistakes allowed animals to spring into existence in the Cambrian explosion. How’s that?

For the sea sapphires, females were having a hard time finding the males. Once upon a time, a male had a mutation that made it develop crystal layers on its outside with precise spacing. (Maybe that took hundreds of mutations, but who knows? We can imagine anything.) The one that reflected better was easier to find by the female. Males that adjusted their layers with different spacing got brighter, and had more kids. But they also attracted predators, so they had to adjust their spacing to go invisible. (They couldn’t see themselves in the mirror to tell if this worked, but it must have, because they survived.) Over billions of years, they became the beautiful little jewels we see today. How’s that? Storytelling is so much fun; that’s how Kipling inspired the Darwin Party.


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