On our good old planet Earth
There is no doubt in my mind that even today in the age of biotechnology and molecular genetics, to discover a new species of plant or animal, to unravel a complex, biochemical pathway, to learn to understand how the brain processes information or to elucidate some component of the neuronal network of an organism and figure out how memory works – they represent exciting moments in the life of a biologist.
But what if you’d find a whole new biocoenosis, a “new world of living organisms” so-to-speak. Wouldn’t that be the ultimate? That’s impossible, maybe on Jupiter’s moon “Europa”, Saturn’s “Enceladus” or maybe even on Mars, but at least not here on Earth, I hear you say. But you are wrong: it is possible. One example are the 1977 discovered and celebrated deep-water hydrothermal vents, in which life is not based on photosynthetic processes by green plants, but on chemosynthetic bacteria that use sulphur compounds (e.g., H2S ) to build organic molecules, which then support a variety of organisms of a food pyramid. Another example comes from Romania and deals with the 5.5 million old “Movile Cave” that contains a small and totally isolated subterranean pond. When discovered in 1986, almost 50 eyeless animal species (the majority of them new to science) were identified to be part of a food chain that was based once again not on photosynthetic plants, but only on H2S and methane-metabolising bacteria. This unique and secluded habitat, in which even a blind predatory leech was present, has been termed an “underground prison” for both aquatic and terrestrial species.
Quite a unique habitat were also the communities that existed in fist-sized bubbles encased by ice of certain frozen Antarctic lakes, which I studied in 1978. A “tip-off” by Professor Alex Wilson of Waikato University led me to find a hidden, until then not seen world of organisms, trapped inside the bubbles of lake-ice. During the brief Antarctic summer, light penetrates through several metres of the lake’s ice and reaches the algae many metres below on the bottom of the lake. Through photosynthetic activity bits of these algae lift off, carried upward by the oxygen they produce. These pieces then get encapsulated at the underside of the lake’s ice cover. Because of their darker coloration, however, the algal pieces absorb more energy than the surrounding clear ice; they melt their immediate surroundings and gradually, ever so slowly and halted every winter due to that season’s darkness, they move upward through the metres of ice that covers the lake the entire year.
The journey of the trapped microcosm from the minute of encasement to the moment of release at the surface may take years, periodically only interrupted by those winter-enforced stoppages mentioned already. Inside each ice-bubble a veritable world of microscopic life forms exists: numerous species of unicellular protozoans (e.g., ciliates and flagellates), slender nematodes, gyrating rotifers, the occasional bear animalcule (tardigrade), bacteria and, of course, microscopic algae, all of them trapped, insulated and isolated from other life for years. And what did I feel when I had taken my first peek into the ice-bubble community that nobody had seen before? Simply childish “awe” and delight is the answer.
© Dr V.B. Meyer-Rochow and http://www.bioforthebiobuff.wordpress.com, 2020.
Unauthorized use and/or duplication of this material without express and written permission from this site’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to V.B Meyer-Rochow and http://www.bioforthebiobuff.wordpress.com with appropriate and specific direction to the original content.