Neil: And I'm Neil.

Rob: Do you ever experience anxiety, Neil?

Neil: Anxiety?

Rob: Yes, you know, a feeling of

being really worried or nervous

without any real reason.

Neil: Well not really, but I know for some

people it can be quite a serious problem.

Rob: Well anxiety may be a result

of natural selection.

Neil: Natural selection? You mean,

the principle behind evolution?

Rob: Yes. The idea that life on this planet

has developed as a result

of random changes

in biology over many many years.

Neil: So why have anxiety, that seems

like a negative rather than

a positive thing to develop?

Rob: Well, we'll find out more in this

programme, but before we do, a quiz.

Charles Darwin is famous for

describing evolution by natural selection.

What was the name of the ship he

travelled on when he made

his discoveries? Was it:

a) HMS Beagle, b) HMS Badger,

or c) HMS Bear?

What do you think, Neil?

Neil: Well I'm pretty sure I know this one,

so I'm not going to give away

the answer just yet.

Rob: Well, you can let me know

at the end of the programme, before

I give the answer.

Right, Dr Randolph Nesse is a doctor

and psychologist. He has written

a lot about how evolution has

an impact on our mental condition,

particularly anxiety. Recently he spoke

on BBC Radio 4's 'Start the Week'

programme about this topic.

Listen out for the answer to this question.

How long did he treat patients

at the University of Michigan for?

Dr Randolph Nesse: Natural selection

has shaped all organisms to have

special states to cope with certain

kinds of circumstances. I treated

patients with anxiety disorders

for 40 years at the University of

Michigan. It was only half way through

that I started realising

that anxiety is there for a good reason.

Rob: So Neil, how long did he treat

patients for at the University of Michigan?

Neil: He says that he did that for 40 years,

but it was only after about 20 years or so

that he realised that we suffer

from anxiety for a good reason.

Rob: We'll find out that reason shortly

but first he said that

natural selection has shaped

all organisms. This means that we are

the result of natural selection. It has

made us what we are.

Neil: And it has made us able to cope

with different situations. To cope

with means being able to deal with,

being able to manage

a difficult situation.

Rob: And anxiety, if it's not too great,

is a way of dealing

with particular situations.

Let's hear from Dr Nesse again.

Dr Randolph Nesse: Natural selection

has shaped all organisms to have

special states to cope

with certain kinds of circumstances.

I treated patients with anxiety disorders

for 40 years at the University of

Michigan. It was only half way through

that I started realising

that anxiety is there for a good reason.

Rob: So why is anxiety a necessary thing,

why is it something that, within reason, is

not a bad emotion. Here's

Dr Nesse talking about his patients

who suffer from too much anxiety.

Dr Randolph Nesse: What you're having

is a normal kind of emergency response

which is great in

life-threatening situations but

for you it's a false alarm like a smoke

detector going off when you burn

the toast. And after that many of my

patients said: 'Oh, that makes

perfect sense, I think I won't need

your help after all, doctor'.

Rob: So what is anxiety?

Neil: Well, it's your body reacting

to danger, like an emergency response,

a warning. In really dangerous

situations, which could harm

you or even kill you, which

Dr Nesse describes as

life-threatening situations, it's a useful

response to warn you to take action or to

prepare for action.

Rob: But some people experience anxiety

when there is no real danger.

It's a false alarm, like when you burn the

toast and the smoke detector alarm

starts or as he says, goes off!

And he says that some patients can feel

less worried after that, when they realise

anxiety is a natural thing.

Let's hear from Dr Nesse again.

Dr Randolph Nesse: What you're

having is a normal kind of emergency

response which is great in

life-threatening situations but

for you it's a false alarm

like a smoke detector going off

when you burn the toast. And after

that many of my patients said : 'Oh, that

makes perfect sense, I think I won't need

your help after all, doctor'.

Rob: Time now to review

today's vocabulary, but first,

let's have the answer to the quiz

question. What was the name of

the ship Charles Darwin travelled on

when he made his discoveries

about evolution? Was it:

a) HMS Beagle, b) HMS Badger,

or c) HMS Bear?

What do you think, Neil?

Neil: Well, I'm pretty sure it's HMS Beagle.

Rob: Well, you are right. Charles Darwin

travelled on HMS Beagle.

Congratulations if you also

knew that. Now, on with today's

vocabulary. We were talking about

anxiety, a feeling of

being worried or scared, a feeling

that something isn't quite right.

Neil: Dr Nesse suggests that anxiety is

a result of natural selection.

This is the principle of

evolution whereby random changes in the

biology of a living thing can make it more

likely to survive in

a particular environment.

Rob: These changes shape the

living thing. They make it what it is.

They help it to cope with

different situations. Which means that

they help it manage or

deal with those situations.

Neil: A life-threatening situation is

a very dangerous situation which

could cause serious

injury or even death.

Rob: And finally there was the

phrasal verb to go off. For example,

if an alarm goes off,

it means that is starts making a loud

noise as a warning. Right,

before any alarms start

to go off here, we need to wrap up.

That's all from us today, do join us

next time. Until then,

you can find us online, on social media

and on our app. Look out for

bbclearningenglish.

Bye for now.

Neil: Goodbye!