Animals that feed on ancient supernovae

Do some animals on earth get their energy from ancient supernovae? It requires energy input to fuse lighter elements into heavy elements such as uranium. In nature this energy input comes from supernovae: heavy elements are formed in supernovae and store a tiny bit of the supernova's energy [1, 2]. As B. Schutz points out in his excellent book [1], this means that nuclear reactors are powered by energy stored from a supernova which most likely occurred around 6 to 7 billion years ago. Even more interestingly, since much of the Earth's internal heat comes from radioactivity, it implies that the Earth is warmed in part by an ancient supernova, so geothermal power also comes from supernovae.

The spectacular deep sea hydrothermal vent animals and bacteria also get energy from the internal heat of the Earth. Earth's heat drives the reactions that form hydrogen sulfide which the bacteria use as an energy source. Hence, some of the energy they use is stored energy from supernovae. The vent animals get their energy from the bacteria. The vent bacteria require both the hydrogen sulfide coming out of the vent and oxygen formed by photosynthesis to get energy by oxidizing the hydrogen sulfide [3]. Therefore, the vent communities do get energy from the sun too, but still, it is remarkable that they get some of their energy from supernovae.

Of course, all of the matter on earth (with the exception of hydrogen) came from ancient stars originally, but it seems even more exciting that the energy that powers the Earth and some Earth life also came from supernovae. And yes, mass and energy are equivalent, but the form of energy that counts here is the free energy: the energy that can drive a system out of equilibrium, and hasn't simply been lost as waste heat or otherwise converted to an unusable form.

I highly recommend two fascinating and very well written books on gravity [1], astronomy [1, 2] and how scientists determine the age of ancient events [2]. These two books are excellent since they delve deeply into how scientists studying these issues have come to their current understanding of them, and what the open questions are, while still being accessible to pretty much anyone with a minimal scientific literacy. I'm only through the first half of Dr. B. Schutz's book on gravity, but so far it's exceptionally good despite a few confusing spots. Dr. M. Hedman's book is one of the most interesting books I've ever read.

(1) B. Schutz (2003) "Gravity: grom the ground up," Cambridge University Press, pp125-126.

(2) M. Hedman (2007) "The Age of Everything: How Science Explores the Past," University of Chicago Press, pp157-158.

(3) C. van Dover (2000) "The Ecology of Deep-Sea Hydrothermal Vents," Princeton University Press.