Not exact matches
Photosynthetic algae
living within the polyps provide the coral
with energy, its vibrant colors, and protection against the acidic byproducts of its respiration.
On the other hand, many anaerobic microbes including methanogens are easily poisoned by oxygen, and the recent discovery of banded sediments
with rusted iron on Akilia Island in West Greenland suggests that oxygen - producing,
photosynthetic microbes (e.g., cyanobacteria)
living on the surface of wet areas to gather sunlight may have developed by the end of this geologic period (3.85 billion years ago) despite continuing bombardment from space.
After over three billion years of evolution in the oceans, multi-cellular
life — beginning
with green algae, fungi, and plants (liverworts, mosses, ferns, then vascular and flowering plants)-- began adapting to land habitats by creating a new «hypersea,» and adding anomalous shades of green to Earth's coloration more than 472 million years ago (Matt Walker, BBC News, October 12, 2010; and Qiu et al, 1998 — more on the evolution of
photosynthetic life and plants on Earth).
As proposed by Andrew Goldsworthy in 1987, cyanobacteria and later chloroplast - related protists and plants developed after microbes that used a purple pigment bacteriorhodopsin that absorbs green light dominated the oceans, and so the new
photosynthetic cyanobacteria were forced to use the left - over light
with chlorophyll that reflects green light, which was too complex to change even after purple - reflecting
photosynthetic lifeforms were no longer dominant (Debora MacKenzie, New Scientist, September 10, 2010 — more on the evolution of
photosynthetic life and plants on Earth).
Earth's much thicker layer of low - level ozone, however, has a much larger contribution from the build - up of molecular oxygen beginning some 2.4 billion years ago from
photosynthetic microbes excreting oxygen as a waste gas, which now along
with plant
life is constantly replenishing Earth's two - atom as well as three - stom ozone oxygen molecules.
Structurally, chlorella is a higher
life form than spirulina, Spirulina is classified as a
photosynthetic bacterium, while chlorella is a plant
with a cell nucleus, making it exactly like the advanced fruits and vegetables we eat everyday.
Recently, laboratory experiments
with live foraminifera have demonstrated that the
photosynthetic activity of algal symbionts and the carbonate ion concentration -LRB-[CO32 --RSB--RRB- of seawater also affect shell d18O values.
The timing of the glaciation also seems to coincide
with the evolution of
photosynthetic life, which would have drastically reduced greenhouse gases through the release of oxygen.
Dr. Kiang also relates this work to research in astrobiology, particularly
with regard to how
photosynthetic activity produces signs of
life at the global scale (e.g., biogenic gases like oxygen and
photosynthetic pigments like chlorophyll) and how these may exhibit adaptations to alternative environments on extrasolar planets, resulting in other «biosignatures» that might be detected by space telescopes.