Nick Lane

And you've got tens of thousands of copies.

Sometimes the very largest one have 700,000 or 800,000 copies of their complete genome.

The energy requirements for copying and expressing all of those genomes are colossal.

What we have with an endosymbiosis, we still have extreme polyploidy, but we've whittled away all the genes that you don't need.

So a symbiosis is based on effectively complementarity, that you've got a symbiont that's doing something for the host cell and the host cell is taking something or giving something back to the endosymbiosis.

So it's a kind of a relationship which is based on mutual needs.

One of them becomes much smaller and that allows the other one to become much larger.

So a symbiosis will do it.

Now, there could be multiple ways of having a symbiosis, but there's no examples on it.

All of these examples of very large bacteria, and they all have extreme polyploidy.

None of them have come up with a complex trafficking network where you effectively take things in and you ship it over there.

There's just not enough genetic space to do that.

I mean, a couple of things I'd say.

Number one, there's a thing called Orgel's second rule, which is that evolution is cleverer than you are.

So, yeah, of course, I cannot say that there's no other way that it could possibly happen.

But it's also hand-waving to say, oh, you know, evolution's so clever, the universe is so big, there's got to be another way that it can happen.

Okay, you know, engage your brain and tell me here's how it's going to work.

Because I cannot say it's the only way it could possibly happen.

Right.

But what I've said is that wet rocky planets are common.