I think it might be very simple. It only takes a couple of votes for a story to hit the front page. Those votes could have come from people like you who are on both sites. Once something hits the front page here, people seem to take it more seriously, which is a bit of a shame since so many quality submissions just slide off the new page because they fail to get the 2 or 3 necessary upvotes.
The responsible upvote on /newest was probably mine. I always upvote the chestnut things I see because I greatly admire it as an example of long-term thinking/projects and the benefits of selective breeding & genetic engineering, and of course the history angles are just cool.
