This isn't proof that they were used, but a likely suggestion. They were present in abundance at the dawn of time and could have been useful in creating the first life form.

208

This tells us that these things that we see out in space can survive interstellar space and successfully be delivered to the surface of a planet.

172

There once was a time that the assumption was that the origin of life, everything from building simple compounds up to complex life, had to happen here on Earth. We've discovered that some very biologically interesting molecules can be formed outside our earthly environment and delivered here.

162

This stuff contains the building blocks of life, and now we can say they're abundant in space. And wherever there's a planet out there, we know that these things are going to be raining down on it. It did here and it does elsewhere.

126

There were a few anomalies in the spectrum that we couldn't explain.

94