I just read this in my oceanography textbook, very very interesting. It seems that deep ocean hydrothermal vents are hot enought to emit light, which can be used by photosynthetic bacteria. This is just 400 degrees centigrade - compared to 3000 for a regular lightbulb filament!! I have wondered whether a bacteria could ever evolve that would utilize the thermal radiation emitted by its surroundings, ie a self powered bacterium - but it seems that this would have happened already around these vents where evolution has been working for millions of years. I hope this article is as interesting to some as it was to me!
Photosynthesis first evolved in bacteria. Algae and plants came later. Apparently one species of animal (a wasp) also performs photosynthesis, using the pigment xanthopterin rather than chlorophyll. So far, four out of six phyla (all but fungi and archaea) have evolved photosynthesis. It must not be such a difficult trick!
Yes. The lower the frequency of radiation, the more difficult it is to focus. The waste heat from an organism tends to just dissipate in all directions. This is, in fact, the final limiting factor on human population. Once we reach something like forty quadrillion people, even if we've solved the problems with feeding, housing, socializing, and consumption of high-frequency solar radiation (which can be focused), our own waste heat can only dissipate into space slowly. Eventually it will simply begin to raise the ambient temperature and people will die of heatstroke before reaching puberty, finally bringing population growth into equilibrium. Back in the 1960s when it seemed like the population was going to keep doubling every thirty years forever, a British scientist felt compelled to figure this out.
Really, a photosynthetic wasp?? I have not heard of it. I read that there is research being done on photosynthetic sea slugs, which appear to get their chloroplasts from bacteria they consume. But a terrestrial wasp which may get part of its energy from sunlight. I don't see why other animals don't obtain this advantage as well. It seems like most animals could use a boost of energy at noon. Cows, which graze outside all day would seem to benefit most from this, along with other grazers. Its no surprise though, evolution isn't all that flexible. I don't see why we should all die of heat stroke if the population would be 40 quadrillion - we just need air conditioning eh? Considering the enormous amount of energy which could be absorbed by the oceans, and then some by the layers of rock which are cooler than the surface, I think that 40 quadrillion (or 40,000,000,000,000,000) is sustainable Please Register or Log in to view the hidden image! It makes me wonder though, even if there was the technology to do all this, is it really a good idea to support endless population growth? If population growth continues the way it has in the 20th century, there will be much worse poverty and quality of life except for the few which have motives to use the masses of people in order to make money. Given that endless energy and food are close at hand, I think it may be worth pondering. For example, what happens when a city runs out of space? Instead of building outwards, it invests its resources in itself and builds upwards.. I think this may be a valid metaphor for what will happen to individual human worth once populations are capped.
Wikipedia says that it is the Oriental hornet, Vespa orientalis, and that this amazing discovery was made at Tel Aviv University. Air conditioning technology has the same limitation that our bodies do: the waste heat is required to dissipate by low frequency radiation, which cannot be focused. Of course we'll mount the units on the surface rather than a mile deep in our warrens, but their waste heat will be just one more component of the waste heat of the rest of civilization and of sixty quadrillion (my memory was a little off) human beings. It cannot be focused and beamed out into the universe the way high frequency radiation can. It can only dissipate by direct radiation into nearby space. That's a slow process, and once we reach that sixty quadrillion figure it will not be fast enough to keep our own ambient temperature from rising. Dr. J. H. Fremlin of the Department of Physics in the University of Birmingham (U.K.) disagreed with you in an article in the October 29, 1964, issue of the New Scientist. I have saved it for all these years but unfortunately it is not digitized so I can't give you a URL to read it for yourself. I data-entered it the old-fashioned way when word processors first became available, but it's far too long to simply post here. He reached the limit of sixty quadrillion by the year 2854, assuming, as I said, that the population would continue to double every thirty years as it had been doing throughout the 20th century up to that point. His math was unremarkable and even he pointed out that a few errors would only make a difference of a couple of centuries. Like most people you are behind the information curve. The second derivative of population went negative around 1980, and the first derivative is almost universally calculated to go negative before the end of this century, with the population peaking just barely into eleven digits. It turns out that prosperity is the best contraceptive. At that point our descendants (I don't know about you, but I won't be around) will have a brand new problem to wrestle with: Every economic system since Adam Smith has assumed a constantly increasing population as its engine of prosperity. The last time the population of our species decreased was long ago in the Paleolithic Era, when our "economy" was subsistence hunting and gathering. Fremlin's math said that building down was the only practical solution. The planet's entire surface would be a mile-deep complex of warrens made up of dwellings about the size of a modern office cubicle, with an equal volume taken up by the infrastructure and transportation corridors (primarily horizontal since one's level would be determined by one's class, however that would be defined in this future). Of course the oceans would be roofed over. The surface would be for photosynthesis, solar energy collectors, waste heat dissipators, and a few parks and zoos for the elite.
Don't worry AlexG it isn't science it is just a bad nightmare!Please Register or Log in to view the hidden image!
Warrens, thats a good word describing the movement of a massively overpopulous humanity underground. I disagree that population growth will ever halt on earth. The recent population explosion was due to an agricultural revolution which resulted in new fertilizers, pesticides and crops. If there is another one, ie synthetic food, shouldn't we expect another population explosion? If food can be produced as cheaply in the future as petrochemicals are now, who is to say we won't be living in warrens even before 2800? I find the idea utterly disgusting. I think that such cancerous growth is an abomination of what life is and would be a grotesque aberration of what living, breathing creatures are. Each one living in a cubicle, running on a treadmill - it should never come to that.. BUT, the truth is that there WILL be another agricultural revolution. There will be a future with virtually free energy (it may be sooner that everyone expects) and food. What is to prevent uncontrolled growth then? I agree. Next step is to speed the earth up to close to the speed of light, so that we can establish an interstellar empire and communicate in real time. Every new colony planet has to be moving this quickly, so that a signal moving at the speed of light will go between planets in no time (from the inhabitant's perspective). But seriously, there are better ways to cool the earth than those mentioned, ie coolers of the second kind.
