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Hello! On my left, there was a wise man who followed a star,

which was a silly thing as it led him back to exactly where he began,

because stars are effectively fixed and only appear to rotate about the pole

because the earth itself is rotating.

But nevertheless, by following that star,

he had to go in a helicopter and saw some volcanoes.

It was brilliant. It's Professor Brian Cox.

On my right, Robin Ince, a man who would be the Ebenezer Scrooge just stand up comedy,

where it not for his refusal to even countenance the existence of the ghost of Christmas yet to come.

And thereby be warned of the dangers of appearing on Let's Dance for Comic Relief

with Melanie Phillips and Widdickham and Peter Hitchens.

Can you imagine that? No, don't, don't.

Today, we're going to take a look at Christmas from an evolutionary perspective,

and not just because, of course, Charles Darwin and Father Christmas have very similar beads.

We will be investigating whether science can explain human behavior at Christmas

and whether evolutionary psychology explains anything at all, in fact.

Robin's effect will be just a branch of philosophy,

and therefore merely for the amusement of well-trained minds with nothing better to do.

As usual, we are joined by our panel of experts.

So Steve Jones is a geneticist with a posh off for snails,

...