> If we posit that evolution typically leads to intelligence and intelligence leads to civilization, then extraterrestrial intelligence would have deduced that

> If we posit that evolution typically leads to intelligence and intelligence leads to civilization, then extraterrestrial intelligence would have deduced that we were going to be coming along at some point. I see two big issues with this: 1) "evolution typically leads to intelligence" is only plausible after the evolution of multicellular life. I don't think there's any reason to suppose "evolution typically leads to multicellular life." Perhaps these aliens are used to a galaxy where 95% of habitable planets are full of primordial soup, where primitive multicellular forms struggle to find a niche. In particular, if most planets are less geologically active than earth, and most solar systems have less asteroids than ours, then perhaps most habitable planets have less extinction events, so there wouldn't be any ecological disruption to spur evolution. 2) "intelligence leads to civilization" is almost certainly false. Orcas have near-human intelligence, including culture and symbolic communication - in fact they might be "smarter" than humans, we don't really know enough about intelligence to answer that. But it will take a bizarre fluke of evolution for them to develop technological civilization, for the simple reason that they don't have hands and there's no selective pressure for them to evolve "proto-hands" - they need the flippers to be good flippers. This is in contrast to primates: we didn't evolve hands to build tools, we evolved hands to climb trees and grab fruits/nuts. It seems far more likely to me that intelligence tends towards super smart crows and dolphins: the physiological capability of building highly advanced tools is orthogonal to intelligence and does not seem inevitable. I'm not saying you're wrong. But my understanding of the almost-science is that the aliens would be wasting a lot of tachyon missiles if they fired at every planet with evidence of photosynthesis / fermentation / etc.