The game developers added one more rule about the game: no cell may live longer than 50 generations. This is supposed to kill all the cells eventually, which is what does happens in the game.
However, when I tried to model this behaviour in my own implementation of the Game of Life, I've got different results. When four dots live together, they usually don't die. When one of them passes away, a new dot gets born in the next generations due to three other dots. Unless two or more dots disappear at the same time, the block will keep itself alive.
So the question is, why do four-dot blocks die in Darwinia and not die in my case?
Update: To be clear, the starting pattern seems to be completely random. During the intro you may press 'g', and everything starts all over again with a random pattern. Also I've changed the link to the video, where you may see a longer version.
Update 2: Tried to add the age of the cell into the birth mechanism, so that a cell past certain age can't give birth to new cells. It definitely works, with the lifespan of 50 generations, setting the last age when a cell can give birth to a new one to, say, 48 generations, works in most cases. Not sure whether the Introversion Software guys used rules like this, though, but it works.