This week, how the discovery of bacteria in tumors could lead to anti-cancer weapons.

If you talk to most surgeons, they will say that tumors are sterile.

And the nature versus nurture debate surrounding musical harmony.

If we really want to understand music, we need to pay attention to other cultures

because in many cases they may hear the world

very differently than we do.

Plus the potential and the pitfalls of tech in health.

This is the nature podcast for July the 21st, 2016.

I'm Charlotte Stoddart.

And I'm Adam Levy.

First up this week, Noah Baker goes in search of the science of what sounds good.

This is the Tristan chord.

It comes from Wagner's 18th century opera Tristan und Isolder, and at the time it caused an uproar.

The qualities of this chord are really quite peculiar.

That's Martin Stokes, Head of music at King's College London.

But it's dissonance all the way down.

In Wagner's Day, this dissonant or clashing chord would conventionally have resolved,

progressing to another altogether less clashing chord,

which in musical terms is called consonant.

Now you could and do something

which makes a bizarre kind of quote unquote sense

but it would make for one of the shortest operas ever.

...