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  • “Exploration is in our nature.” - Carl Sagan

SETI: Is Intelligence Commonplace?

SETI: Is Intelligence Commonplace?
SETI: Is Intelligence Commonplace? The Search for Extraterrestrial Intelligence is based on the assumption that intelligence of a technological sort has arisen on more than one planet in our galaxy. On Earth, some forms of life exhibit intelligence; others do not. Ravens have been seen making and using tools; mushrooms and algae have not. Dolphins, like humans, have evolved a complex language, and bonobos display many behaviors remarkably similar to human activities. But of all the life-forms that have come and gone on Earth, only one has built radio telescopes to listen for signals from other life-forms. The likelihood of a similar life-form existing on another planet is a topic for lively debate. Clockwise from left: Diana L. Stratton, David M. Dennis, Randy Morse, Mike Bacon and Roy Toft (all Tom Stack & Associates). Bottom: Seth Shostak