Australia Coral Reef
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Obtaining energy is a basic and fundamental process for the survival of a living being and therefore, from the beginning of life on earth homo sapiens had to develop as a hunter and animals as great predators.
Grizzly Bear in Kodiak island of Alaska are the largest brown bears in the world. Every year they wait on the coast at the arrival of the salmon to feed themselves.
The catch sets in motion a basic process in the life of all survivors on the planet earth. The process of obtaining the energy necessary for a living body to function.
The energy used by the bears to walk to here every year is more than compensated for by the energy obtained, so much so that many individuals literally cannot assimilate such enormous quantities of food.
But killing does not always bring such rich rewards.
Man, like the animal he is, also forms part of the energy cycle.
Man learnt how to use the energy of fire, and around the fire his prehensile hands developed a privileged brain capable of inventing the claws the bear did not have.
But speech was the real motor of change.
Through language, inventions were passed on from generation to generation, making it possible for humans to colonise the earth, as they were able to obtain energy from other living beings wherever they were.
Just as these Australian aborigines still do in the twenty-first century, human beings replaced biological evolution with cultural evolution, transforming the accumulation of traditions into the most successful of all adaptive mechanisms.
The final aim of all this is precisely the same need that spurs the bears on to catch the salmon - to obtain energy in an efficient manner.
But the success of mankind as a thinking predator began in relatively recent times. Long before us, other animals honed their hunting techniques, aided by natural selection, a slow but surprisingly efficient process.
On the Galapagos Islands lives a bird that is a good example of natural selection, in this case to catch fish: the brown pelican. Here, the Pacific Ocean brings fish to this young volcanic coast over 600 miles from the American continent.
The method would appear to be simple.
But it’s a method not all predators can use – first, you have to know how to fly. A bird like this, also equipped with its very own fishing net, can permit itself the luxury of choosing a particular fish.
Since the reptiles ruled over the earth, birds have without a doubt achieved the most spectacular anatomical adaptations when it comes to fishing, not only here in Galapagos, but throughout the planet.