Wednesday, June 05, 2013

A garden of earthly delights


A few weeks ago, Paul drew our attention to a rather unusual "flower garden," seen here on the cover of Science (click to enlarge). Not flowers at all, but non-living crystals, micrometers in size, grown in solution and here colored artificially by computer to more dramatically resemble flowers. This whole garden would fit on the period at the end of this sentence. These, and other crystalline forms, can be rationally grown by changing such parameters as pH level, temperature, and carbon-dioxide concentration.

Neat, but nothing compared to what nature does all on her own.

Consider the foraminifera (forams), tiny amoeboid creatures that live mostly in sea-floor sediments. They construct a bewildering variety of shells, typically sub-millimeter in size. You can see a photographic atlas of foraminifera here, on my daughter's web site.

For much of her research into past climates, Mo has relied upon sediment "cores" pulled up from the bottom of the sea. These are typically full of fossil forams whose forms, colors and composition contain multiple clues to the conditions in the sea (and by extension, the atmosphere) when the forams were alive. I previously wrote about one such exercise here.

As sea-floor sediments accumulate, they gather and bury a history of the Earth, page by page, reaching millions of years into the past.