Nick Lane

having me here.

This is fun.

I love talking about this kind of thing.

So eukaryotes, what's a eukaryote?

It's basically the cells that make us up, but also make up plants and make up things like amoeba, fungi, algae.

So basically everything that's large and complex that you can see is composed of this one cell type called the eukaryotic cell.

And we have a nucleus where all the DNA is, where all the genes are, and then all those kind of

machinery cell membranes and things.

There's just basically a lot of kit in these cells.

And the weirdness is, if you look inside a plant cell or a fungal cell, it looks exactly the same under an electron microscope as one of our cells.

But they have a completely different lifestyle.

So why would they have all the same kit if they evolved to be a single-celled alga living in an ocean doing photosynthesis?

It's still got the same kit that our cells have.

So we know that because they share all of these things, they arose once.

in the whole history of life on Earth, there could have been multiple origins, but there's no evidence for that.

If there was, it disappeared without trace.

So we've got this kind of singularity, which happened about 2 billion years ago, about 2 billion years into the history of life on Earth.

Then this thing happens once that gives rise to all complex life on Earth.

And the one thing which I guess you could conclude from that is bacteria and archaea

In terms of their genetic repertoire, they're actually, they've got a lot more genes, a lot more versatility than eukaryotes do.