Okay, as if "˜species' and "˜life' were not fuzzy enough, let's consider the rock-solid notion of "˜self-replication':

VENTER: Does it need to be self-replicating?

SHAPIRO: It needs to be reproduced. The idea of a replicator, of DNA copying itself. I have a tie like that: it shows nucleotides swimming up to DNA, and miraculously one strand forms a double helix, but anyone who teaches biochemistry knows that doesn't happen "” no way. There are dozens of proteins that come in and get involved in the action, and untwist the twists of DNA, and prime it and close the gaps in DNA.

VENTER: I wasn't describing a mechanism, just, the term 'self-replicating'.

SHAPIRO: DNA isn't self-replicating.

VENTER: No, I'm not talking about DNA.

SHAPIRO: And RNA as far as I know isn't "” virus needs an entire cell filled with ribosomes and god knows what "” mitochondria.

VENTER: Methanococcus is self-replicating.

SHAPIRO: Methanococcus is self-replicating, and if it lives and grows and changes eventually into different strains, that's alive.

LLOYD: So is a virus alive?

SHAPIRO: That's a question of how you want to define it.

VENTER: Is it not self-replicating.

LLOYD: I'm not self-replicating either. I have children and neither of them look anything like me.

SHAPIRO: The difficulties in these definitions are notorious. Is a nun alive? She's certainly not replicating. Is a mule alive? It has most of other properties, but it's sterile and has no offspring.

CHURCH: Its cells are alive.

SHAPIRO: Its cells are alive.

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