"Only one species of the billions of species that have existed on Earth has shown an aptitude for radios and even we failed to build one during the first 99% of our 7 million year history," observed Charles Lineweaver a noted astrobiologist at the Australian National University.
Let's take a quick look at the plot of the 1968 movie, "Planet of the Apes," with Charlton Heston playing the role of Taylor, an astronaut on an interstellar journey. After traveling for over two thousand years at nearly the speed of light (during which the astronaut crew ages only 18 months due to time dilation), the spacecraft crash lands on a planet that has oxygen comprising 20 percent of the atmosphere, and a 23 hour 56 minute sidereal period.
Unsure of where in the galaxy they are, they soon discover that on this strange new world, chimpanzees and other primates have evolved to become human-like both physically and in the development of their society. Human beings, mute beasts that are captured and used for scientific experimentation, occupy a lower rung in this intelligence hierarchy.
This planet has corn, horses, and gorillas who use rifles and chimpanzees who use photographic equipment. It never occurs to them that this is, in fact, the Earth. Charlton Heston falls in love with a mute Homo sapien, and they ride away and discover the remnants of the Statue of Liberty. Only then do they realize this is planet Earth, there's no going home. They're there; as a subordinate species.
In a 2008 interview with Astrobiology, Lineweaver emphasizes that the "Planet of the Apes" hypothesis is that "such a niche exists - that human beings developed a big brain because there was selection pressure to move into this evolutionary niche. Another way of saying it is that smart organisms are better off and more fit than stupider organisms in all kinds of environments, and therefore we should expect any type of critters anywhere in the universe to get smarter like we consider ourselves to be.
"Carl Sagan called them "functionally equivalent humans." That's what the SETI program has been based on. There is a big polarization in science between physical scientists like Paul Davies and Carl Sagan and Frank Drake on the one hand, and biologists like Ernst Mayr and George Gaylord Simpson who say that life is so quirky that human beings would never evolve again. If a species goes extinct, it doesn't come back. There may be a niche that opens when a species goes extinct, but the same species or even anything similar to it does not re-evolve into that niche.
"If intelligence is good for every environment, we would see a trend in the encephalization quotient among all organisms as a function of time. The data does not show that. The evidence on Earth points to exactly the opposite conclusion. Earth had independent experiments in evolution thanks to continental drift. New Zealand, Madagascar, India, South America... half a dozen experiments over 10, 20, 50, even 100 million years of independent evolution did not produce anything that was more human-like than when it started. So it's a silly idea to think that species will evolve toward us.
"If you go to these other continents and ask zoologists," observed Australian astrobiologist Charles Lineweaver, "What do you think is the smartest thing there? Is it trying to become human? Is it any closer today than it was 50 million years ago to building a radio telescope? I think the answer would be no. If that's the answer, then there is no trend toward human-like intelligence, and this whole idea of intelligence being convergent is just an empty claim based on what we want to believe about ourselves. Only one species of the billions of species that have existed on Earth has shown an aptitude for radios and even we failed to build one during the first 99% of our 7 million year history."
Current estimates say that are some 100 billion stars just in our Milky Way galaxy and 10 billion trillion stars in the observable universe.There are more stars in existence than days since the universe was formed.Yet, the deafening silence from space is not surprising. There must be other radio transmitters out there, but perhaps none in our galaxy. If homo sapiens survive long enough, time will tell.
We should not expect to see any other forms of life that are genetically, functionally and intellectually similar to us." Lineweaver emphasizes. "I strongly suspect that our closest relatives in the universe are here on Earth, and they're not likely to be elsewhere."
Maybe NASA read Lineweaver's interview: their searches have been reconfigured to explore for non-carbon forms of life and the totally unknown.
The Daily Galaxy via Astrobio.net and spacedaily.com
Image credit: ALMA Observatory and pinterest.com