Intelligent, Technological Exospecies Likely Evolved Before Us --"And They're Extinct"
(http://www.dailygalaxy.com/.a/6a00d8341bf7f753ef01b7c84c843d970b-pi)
Are humans unique and alone in the vast universe? This question--summed up in the famous Drake equation--has for a half-century been one of the most intractable and uncertain in science. But new research shows that the recent discoveries of exoplanets combined with a broader approach to the question makes it possible to assign a new empirically valid probability to whether any other advanced technological civilizations have ever existed.
And it shows that unless the odds of advanced life evolving on a habitable planet are astonishingly low, then human kind is not the universe's first technological, or advanced, civilization.
The paper, published in Astrobiology, also shows for the first time just what "pessimism" or "optimism" mean when it comes to estimating the likelihood of advanced extraterrestrial life.
"The question of whether advanced civilizations exist elsewhere in the universe has always been vexed with three large uncertainties in the Drake equation," said Adam Frank, professor of physics and astronomy at the University of Rochester and co-author of the paper. "We've known for a long time approximately how many stars exist. We didn't know how many of those stars had planets that could potentially harbor life, how often life might evolve and lead to intelligent beings, and how long any civilizations might last before becoming extinct."
"Thanks to NASA's Kepler satellite and other searches, we now know that roughly one-fifth of stars have planets in "habitable zones," where temperatures could support life as we know it. So one of the three big uncertainties has now been constrained."
---
More at link -
http://www.dailygalaxy.com/my_weblog/2016/04/other-intelligent-technology-producing-species-likely-evolved-before-us-and-theyre-extinct.html (http://www.dailygalaxy.com/my_weblog/2016/04/other-intelligent-technology-producing-species-likely-evolved-before-us-and-theyre-extinct.html)
This looks like another take on the Fermi Paradox
https://en.wikipedia.org/wiki/Fermi_paradox
http://www.bibliotecapleyades.net/vida_alien/alien_contact48.htm