Maybe this is obvious, but I always enjoy thinking of it: except for a comparatively little bit of radioactively decaying material inside the earth, and some tidal forces, all energy on this planet, every single joule of energy ever expended is just stored sunlight.
Sunlight hits photosynthesizing bacteria which create biological fuel molecules called sugars. Plants store these sugars and convert the energy in them into leaves and roots and organic material. Animals eat the plants and convert the stored energy into useful work. Plants and animals die, and the stored energy in their bodies is consumed by other life which turns them into work. Sometimes it gets captured by the earth before it can decompose and over very long timespans, it gets compressed and turned into super energy dense organic material called coal or petroleum.
All the gasoline we're expending, all the coal and natural gas we're burning is just stored sunlight in very efficient organic batteries. Even the wind energy we're capturing is created by the external energy of the sun injecting heat into our earth system and creating work.
> except for a comparatively little bit of radioactively decaying material inside the earth, and some tidal forces
There's also geothermal energy.
EDIT: I erased what I said about tidal forces. I thought it referred to all currents in the ocean, but it specifically refers to the periodic pull the moon has on the Earth, to greater effect, on its water.
I didn't know that most geothermal energy was from fission, but as the article says, not all geothermal energy comes from fission. There's also the release of heat as the outer core solidifies into the inner core. That's what I previously thought that most geothermal energy was.
Tidal is another exception, and geothermal is both radioactive heat and latent heat of gravitational formation (about half each).
But fossil fuels? That's burning buried sunshine. At a rate of about 5 million times faster than it formed. 23 tonnes of ancient biomass per litre of petrol -- nearly 100 tonnes per gallon.
This made me realize that there are no lifeforms getting energy by mechanical means (harness wind, waves, tides). That seems like an oversight on evolution's part!
There are, however, plants and animals that harness mechanical energy as a survival strategy, which might amount to the same thing. For example when dandelion seeds get spread in the wind, or fish swimming along ocean currents.
I think a good rule of thumb, given the extreme diversity of the biological world, is that if a specific biological mechanism hasn't evolved in 4 billion years of evolution there's probably a good reason for it.
Biological evolution does a pretty poor job of mechanical adaptations in general. For example in the entire history of life on Earth there's no instance of a true wheel being developed.
I'd say evolution is really good at chemical engineering, decent at aerospace engineering, okay-isn at electrical/computer engineering, and incompetent at mechanical engineering.
We can harness the equivalent timeframes of evolution with simple GAs over quick runs (<1m), but we get nowhere near the results. What is the secret sauce?
The building blocks of life are far more complicated and are being run with enormous populations. 1m generations are less than 100 years for a lot of bacteria and the population they are working with is stupidly large.
I just tested one of my GA's and it's solving a logic problem with 3k pop, 30 children per gen, in 1-2k generations. If I make it 300 children per gen it solves in 150-300 generations. 1500 children is solving in 30-50 generatikons. Now imagine 5 x 10^30 pop with 10^30 children per generation, over millions of generations.
Where do you get those population sizes from? My research shows on the order of 10^18 organisms on earth. And the shortest generation time is on the order of minutes for bacteria. As we go up the complexity scale to higher animals reproduction time drops drastically. If its just a matter of reproduction cycles, bacteria should be more advanced than humans. How does this efficiency jump happen where suddenly we only need a few offspring over the course of decades to outpaced the evolution of much more fecund populations? Additionally, humans should be evolving at a blinding rate with each new generation compared to bacteria. The whole thing doesn't make a lot of sense to me.
I googled "number of bacteria in the world" and the number is around 5 * 10^30. I mean, there are 7 * 10^9 humans and each human has trillions (10^12) bacteria, so the human population + bacteria in the body totals over 20^22 living organisms alone.
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[ 2.6 ms ] story [ 65.2 ms ] threadHey, we’ve got nuclear reactions now too!
Sunlight hits photosynthesizing bacteria which create biological fuel molecules called sugars. Plants store these sugars and convert the energy in them into leaves and roots and organic material. Animals eat the plants and convert the stored energy into useful work. Plants and animals die, and the stored energy in their bodies is consumed by other life which turns them into work. Sometimes it gets captured by the earth before it can decompose and over very long timespans, it gets compressed and turned into super energy dense organic material called coal or petroleum.
All the gasoline we're expending, all the coal and natural gas we're burning is just stored sunlight in very efficient organic batteries. Even the wind energy we're capturing is created by the external energy of the sun injecting heat into our earth system and creating work.
There's also geothermal energy.
EDIT: I erased what I said about tidal forces. I thought it referred to all currents in the ocean, but it specifically refers to the periodic pull the moon has on the Earth, to greater effect, on its water.
The rest is likely residual from gravitational and tidal friction/compression and possibly other unknown sources.
Tidal is another exception, and geothermal is both radioactive heat and latent heat of gravitational formation (about half each).
But fossil fuels? That's burning buried sunshine. At a rate of about 5 million times faster than it formed. 23 tonnes of ancient biomass per litre of petrol -- nearly 100 tonnes per gallon.
See Jeffrey S. Dukes (2003):
https://dge.carnegiescience.edu/DGE/Dukes/Dukes_ClimChange1....
I think a good rule of thumb, given the extreme diversity of the biological world, is that if a specific biological mechanism hasn't evolved in 4 billion years of evolution there's probably a good reason for it.
I'd say evolution is really good at chemical engineering, decent at aerospace engineering, okay-isn at electrical/computer engineering, and incompetent at mechanical engineering.
I just tested one of my GA's and it's solving a logic problem with 3k pop, 30 children per gen, in 1-2k generations. If I make it 300 children per gen it solves in 150-300 generations. 1500 children is solving in 30-50 generatikons. Now imagine 5 x 10^30 pop with 10^30 children per generation, over millions of generations.