Norman Swan

Once upon a time, people thought that the pineal gland in the brain was vestigial.

Indeed.

So just because you lack understanding of what an organ does, does not mean that it's actually an unnecessary part of the body.

And as we learn more, we find that things that may have looked as though they were vestigial may in fact not be.

Well, in fact, they used to whip them out even before you got infected as a prophylactic procedure, classically on the kitchen table.

Yeah, we didn't have a very big kitchen table, so...

We didn't have a kitchen table.

We couldn't afford one.

Yeah.

So the tonsils can be an annoying organ, particularly in childhood, repeated infections.

They can become enlarged, obstruct breathing, all sorts of issues with tonsils.

And the temptation has always been to remove them to improve your quality of life and perhaps risk of serious infection occurring like a tonsillar abscess, for example, in the neck.

But it turns out that tonsils are not a vestigial organ.

Yeah, they're part of our defences against the external world, infections coming in to the body.

Yeah, so it's not surprising they become infected themselves.

But it turns out that they are part of the way our immune system works.

They produce cytokines, which are the short-acting or even long-acting chemicals which stimulate and control our immune system.

They're involved in B cells, which are cells which produce antibodies.

They're involved in...

in the production of IgA, which is again not surprising because IgA is the antibody that helps us with surface immunity.