Smart aliens? Unlikely, says scientist

Stars may be bright, but any life on other planets is probably not.

Visiting Australian astrobiologist Charley Lineweaver says if there is life out in space it is unlikely to show intelligence as we know it.

He doubts the quest for life beyond Earth will uncover aliens similar to humans.

"I think that tree outside my window is more closely related to me than anything we will find in outer space. Things do not converge to being like a human being," he said. "We should assume there isn't intelligent life out there. We see no evidence based on evolution on Earth for a tendency to develop human-like intelligence."

Lineweaver gave a public lecture at Canterbury University last week. He is a senior fellow of the Planetary Science Institute in Canberra and a researcher at the Australian National University.

He said that the search was on beyond the solar system for an Earth-sized planet that might have a similar "biosignature", and probability supporting life, as Earth.

"We have found about 300 large Jupiter-size masses, or they are very, very young and hot planets further away from their host stars," he said.

"We have found `earths' about five times the size of Earth, but we have yet to find an Earth-like planet around a Sun-like star.

"The major goal of quite a few scientists around the world is to find that Earth-like planet."

The Kepler Mission to be launched next year would help scientists find those planets by studying how much they dimmed light when they moved in front of their stars.

The amount of dimming would signify how big the planet was and the size of its orbit.

Scientists did not know if the components of life on Earth amino acids, alcohols and sugars had combined the same way elsewhere.

Lineweaver said there was strong evidence on Earth that, in the absence of humans and over many millions of years, creatures did not evolve towards having human-like intelligence.

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