Shil DasSarma - first life pink?

Professor Shil DasSarma University of Maryland marinebiogech.org

Ker Than writes about a suggestion by microbial genetist Shiladitya DasSarma from University of Maryland Center of Marine Biotechnology, that early life on Earth may not have been green nor black but rather pink!

The earliest life on Earth might have been just as purple as it is green today, a scientist claims.

Ancient microbes might have used a molecule other than chlorophyll to harness the Sun's rays, one that gave the organisms a violet hue.

Chlorophyll, the main photosynthetic pigment of plants, absorbs mainly blue and red wavelengths from the Sun and reflects green ones, and it is this reflected light that gives plants their leafy color. This fact puzzles some biologists because the sun transmits most of its energy in the green part of the visible spectrum.

"Chlorophyll was forced to make use of the blue and red light, since all the green light was absorbed by the purple membrane-containing organisms," said William Sparks, an astronomer at the Space Telescope Science Institute (STScI) in Maryland, who helped DasSarma develop his idea.
LiveScience 2007

As a beginner student of the subject, IMHO discussion of the pigment colours on early life forms upon Earth is a good sample of using natural selection as the main tool for explaining the evolution of life.

The idea is there and is fitted to the theoretical discussion of how green might have become the dominant colour and chlorophyll take the leading position in plant life.

Let us suppose a fight for survival on early Earth - let us assume that we need sun to generate energy - who might be competing forcing the choice between black, pink, blue and green?

Indeed, a good show case of evolutionary biology at work explaining the greenness of the plant world!