0:00

This is a Triple J Podcast. Could

0:02

your destination and descent impact

0:04

your aeroplane headache? What

0:06

is data on your computer made of and

0:09

is the last born child elite? Youngest children?

0:11

Razz up. My name's Lucy Smith. You are

0:14

listening to Science with Dr Karl. We get

0:16

into all of that and more in this

0:18

episode. Let's do it. Karl,

0:22

how are you doing this week? Episode PCHK. What's

0:24

going on? Life is

0:26

good. And we're

0:28

finally realizing something is

0:30

a result of us having switched over

0:32

to massive computer use in 2009.

0:35

So computers are around, but it was 2009 when

0:38

computers became available to everybody without

0:40

their parents watching when the smartphones

0:42

became smart enough. So

0:45

true. So there was the Apple iPhone

0:47

1 and 2, which sucked and they all came good

0:49

in 2009. And one thing

0:51

we've found is that if you study,

0:54

if you're taking notes of

0:57

anything, if you type it in,

0:59

you don't remember it as much as if

1:01

you write it down. So when you write,

1:03

you go A and B

1:05

and C and there's very different motions with your hands

1:07

and this is triggered by different parts of the brain.

1:10

Whereas when you're typing, whether you type A or B

1:12

or C, it's just sort of tap, tap, tap, and

1:14

you move your finger a bit left or right, but

1:16

just tap. And it turns out that much less of

1:19

your brain is involved when you're

1:21

typing. And so your recall is so

1:23

much less. And we didn't know this

1:25

until we tried it and we've been

1:27

trying it for about 2009 to now.

1:30

What's that? Uh, 15 years or something. 15

1:32

years. Yeah. And so we're now finding that

1:35

people who learn by typing

1:37

stuff, they really don't remember it

1:39

and so they can take notes of an entire meeting and

1:41

I say, what happened in the meeting? No idea. If you

1:43

write it down, you remember it. Isn't that weird? Well, we're

1:45

just discovering it by doing it. That's so true. I

1:47

used to write out all of my study notes

1:49

by hand. Yeah. Oh, you're so

1:52

good. And we do have a lot of,

1:54

a lot of what they call handing off.

1:56

We're handing off a lot of your memory.

1:58

It's called cognitive offloading. I used. remember at

2:00

my peak maybe 20 phone numbers

2:02

and I have met people who the

2:05

number of phone numbers they know is zero

2:07

including their own. They don't know their own

2:09

phone number. They'll say I'll ring you. The

2:12

other phone number it's something something look

2:14

just I'll ring you and they don't know their

2:16

own phone number and they don't need to but

2:18

as the actress did say to the bishop if

2:20

you don't use it you lose it. Alright

2:22

if you've got a question about memory 0439 757 555

2:24

we'll kick it off with Tristan from Kaima. Tristan you

2:26

got a question

2:30

about space what is it? Yeah

2:32

Guy I've heard astronauts say

2:35

that space kind of smells

2:37

like a combination of burnt

2:40

meat and burnt hair or something but

2:42

if space is a vacuum how is there

2:45

a smell in there like how

2:47

does the smell transport if there's no air

2:49

like you know does it go on to

2:51

the space suits when they do a spacewalk

2:53

and then when they go into the air

2:55

like they can smell space suits or how

2:57

is there smell in space? Ah the

3:00

last one that you just mentioned and it is

3:02

actually mentioned in the new series on some streaming

3:04

network called constellation

3:07

and it's about how come hey if astronauts

3:09

can smell burnt toast oh my god that

3:11

means that quantum reality isn't real and I

3:13

can go back through time blah blah blah

3:15

all that crap but the point is that

3:17

they don't smell it if they

3:19

go out in space without a space suit because they

3:21

die so your

3:24

suggestion is right so they go out into space

3:26

and they come back and

3:28

their space suit has picked up something but

3:30

there's not a lot of molecules out there

3:32

and then what happens is a phenomenon called

3:34

outgassing and then suddenly they can smell the

3:37

burnt toast now on one hand we

3:39

firstly we don't understand it because the number of

3:41

molecules of stuff out there is really small and

3:43

to think that there's enough to go onto their

3:46

space suit and then go into the air to

3:48

give them the smell of burnt toast like sometimes

3:52

in your kitchen you don't smell a burnt toast

3:54

until it's fairly burnt so you need a lot

3:56

of molecules yeah not having a me the

3:58

other day yeah I had I had I

4:01

had something burning in the kitchen and I thought

4:03

it was the chicken that I had on the

4:05

stove. And then I realised I'd been baking croutons

4:08

in the oven and then when I opened up

4:10

the oven just this black

4:12

smoke came out and I was like shit!

4:15

But I fully in that moment I thought it was what

4:17

was happening on the stovetop. I turned off the stove, I

4:19

got it off there but it didn't register

4:22

for a minute until I like to

4:24

really specify where the smell was coming

4:26

from and it was coming from below me not in front of

4:28

me. So interesting. So that's why

4:30

they say it's a problem that there's not

4:33

enough molecules that would land on a spacesuit

4:35

to trigger them but there's something going on

4:37

and the answer is it happens occasionally and

4:40

they don't fully understand why. And

4:42

there's mysteries in space. Like we still, we're getting close

4:44

to working out how galaxies form and how they all

4:46

seem to have a black hole in the middle but

4:48

we haven't quite got there yet. Nor

4:51

burnt toast in space. Sorry. Does that help

4:53

Tristan? Yes, good answer. Thanks. Thank

4:56

you Dr Tristan. Burnt hair? Now

4:59

that is a really strong smell. Yeah,

5:01

Bronwyn in Canberra. What's

5:03

your question? Hi,

5:05

my question is about when

5:08

you get like a split in your nail,

5:11

like finger or toe nail, and

5:13

you like cut your

5:15

nail below where the split is, how is

5:17

it that the split grows back into your

5:20

nail? Ah, and is this a case

5:22

where it's been growing back for a

5:24

long time, like year after year? Yes.

5:27

Oh, I'm sorry. Yeah, my husband and I both have one of these.

5:30

Oh, do you have them on the same

5:32

fingers as an act of professional, loyal, loving

5:34

solidarity? Yes, I have kids. No,

5:37

unfortunately. Unfortunately,

5:40

I think what you've done

5:42

is you've damaged the nail

5:44

bed. So go into Wikipedia

5:46

and look at the pictures there and the

5:49

nail bed is sort of way back high

5:51

at the base of your nail and you've

5:53

caused trauma all the way back

5:55

to your nail bed and because your

5:57

nail bed, which turns basically turns blood.

6:01

into keratin which is kind

6:03

of amazing. So

6:24

if the nail bed has been damaged I

6:30

think if I'm not sure, I'm sorry.

7:00

That little bit of splits. Exactly and even

7:02

when I cut it right back it'll

7:04

still grow out and like the split will still grow

7:07

in the same place. I

7:09

don't know. Now see what

7:11

you can do is an experiment where you

7:13

get a nail file, you know a little

7:15

triangular one and right near the lunule or

7:17

white area, you make a little nick and

7:20

then you know not a deep one, you don't want

7:22

to damage yourself and you can watch it progress up

7:24

your fingernail over a period of time. So it's not

7:26

as though the nail at the very

7:29

tip was created at the tip, it was created

7:31

at the base and then migrated up and

7:33

you can see this when you put nail polish on.

7:36

So the answer is I don't know and what we

7:38

need is a dermatologist because fingernails belong to

7:40

them. So what's the magic number Dr Lucy

7:42

that a dermatologist should ring on to explain

7:44

this to us? Yeah text

7:46

in 043975755 Bronwyn when did this happen? Well

7:50

the one of my thumb has been happening

7:52

for about a few years now. Yeah,

7:56

so every time I cut it back when

7:58

it gets to a certain length. It's

8:00

split like like the split seems to either

8:02

appear again or it or just it always

8:04

break in exactly the same spot And

8:07

then with my husband's toenail, he's

8:09

got like a permanent split But

8:11

it's just at that white bit

8:13

of the nail past the pink

8:16

bit Wow, so it's

8:18

not on the pink bit It

8:20

only appears when it migrates past the pink

8:22

bit and just floating in space where it

8:24

can annoy you by bumping into things Yeah,

8:27

all I can think of is maybe there's a bit of

8:29

damage to the nail bed where there's a deficient

8:32

or bad form of keratin being made that

8:34

is a little bit structurally weak and while

8:36

it's migrating outwards in the P-bit, you know

8:38

like the centimeter or so It doesn't matter

8:41

because it's got good stuff in front of

8:43

it and behind it And then maybe when

8:45

it starts hanging in space by itself, then

8:47

the slight deficiency Oh, yeah,

8:49

I don't know I don't have the

8:52

dermatological knowledge to know this Oh,

8:55

come on down dermatologist and give us your answer,

8:58

please. We've got Daniel in Melbourne Daniel. You

9:00

got a question about clouds Yeah,

9:03

so I was wondering why The

9:06

water vapor in clouds clumps together

9:08

and forms clouds rather than as

9:10

one singular sort of mist over

9:13

the atmosphere In

9:15

physics if you're lucky you can boil things down

9:17

to two forces which act against each other and

9:19

then it's just the balance of those So

9:22

in the case of water molecules, that's what you're looking

9:24

at because that's what clouds are made of Look

9:27

at a water molecule itself. It's like a

9:29

little boomerang It's almost a

9:31

right angle, but a bit bigger 104.5 degrees instead of 90 and at

9:33

the point of the boomerang The

9:39

middle bit you got H2O So

9:41

you got an O and you got two H's

9:43

on the outside now on one hand they

9:46

attract each other because of weak

9:49

Electrostatic attraction because the hydrogen is

9:52

slightly positive the oxygen is slightly

9:54

negative But on the other hand

9:56

you've got temperature as a temperature

9:58

rises they shake and the

10:00

more the temperature rises, the more they

10:02

shake and that overcomes the weak attractive

10:04

force. So during a cloud, when a

10:06

cloud happens, the temperature is low enough,

10:08

you're high enough above the ground, that

10:10

different parts of it at different temperatures,

10:12

if the temperature is low, they will

10:14

tend to clump. If it's just a

10:16

little bit higher, they'll tend to de-clump,

10:18

if that's a word. So is that

10:20

what you're sort of asking? Am I

10:22

heading down the right pathway? Yeah,

10:24

I think you are. So you're saying

10:26

that in clouds you've got sort of clumpy bits and not

10:29

clumpy bits? We are a

10:32

cloud expert and the Greek

10:34

word is nephrolos, so I think a nephrolologist

10:36

or somebody who

10:38

works for the BOM, it would be lovely,

10:40

to explain to us, is there actually a

10:43

relationship between the clumpiness of the cloud, how opaque

10:45

it is and the temperature? I'm guessing there is,

10:48

but I'm not an expert, but I reckon from

10:50

basic physics, that would be

10:52

the situation. Thanks Daniel. Now,

10:56

Karl, we had a caller early in a bromwin

10:58

who was having a split in her nail and

11:00

it wasn't starting on the pink end of the

11:02

nail bed, it was when it grew out, boom,

11:05

and then that's when it would split once it

11:07

was white and kind of off the skin, so

11:09

to speak. So on the central

11:11

coast, I had the nail issue start

11:14

in pregnancy and lasted about five years,

11:16

tried everything, polish, glues, nothing worked but

11:18

it cleared up itself, no idea how

11:20

or why. Someone else, they

11:23

said mine was the same on my thumbnail, it

11:25

took about ten years and it finally came good,

11:27

it was so good to have it back and not

11:29

splitting as it grew. Karl, I

11:31

don't know if you can relate to this, but

11:33

there's nothing worse than when you've got a

11:35

split in your nail or a lift and

11:37

you're just running your fingers through your hair

11:39

and then a single strand of hair gets

11:41

caught. Oh yes. Horrible.

11:44

Can nail polish or

11:47

epoxy help in that situation? I

11:50

don't really know because unless you're fusing it

11:52

together, unless you're getting maybe an acrylic nail

11:54

and putting it on top, you've

11:56

got to cover it in a way. sensitive

12:00

so you can run your

12:02

fingernail across the surface and feel a

12:04

change of very tiny

12:06

fractions of a millimeter just with

12:08

the tip of your fingernail and

12:10

so they do uniquely sort

12:13

of send sensation back to the pressure

12:15

sensors up at the nail bed. It's

12:17

like when you cut your nail a little too short

12:19

and you can feel the metal of the clipper on

12:21

your nail. That is annoying. The worst.

12:24

Okay, we've got David and Sydney here. Dr David, welcome.

12:27

David, you've got a question about headaches

12:29

but a particular kind. What's going on?

12:31

How are you going? Hey Dr Carl, Dr Lucy. Dr

12:33

David. Yeah, I do a fair bit of

12:36

flying for work and when I descend

12:38

into certain airports you get a lot

12:40

of pressure and a lot of pain

12:42

and nerves above my eyebrow on one

12:45

side of my face but it's mainly only

12:47

landing in Sydney and it's when the pilot

12:49

descends and obviously I'm chewing gum to clean

12:52

my ears and I just was wondering

12:54

what might be happening. Is it cabin pressure

12:56

or? Airplane

12:59

headaches, Dr Carl. What's going on? Yeah, I

13:01

googled it. What did Google tell you? To

13:05

try taking antihistamine. Oh,

13:07

really? Or

13:11

another product which they actually were just

13:13

using there. It was like an ad

13:15

but they said antihistamine. So

13:18

there's somebody who's trying to sell you

13:20

something who can make a profit from

13:22

it and in Australia the

13:24

regulations are that medical doctors are

13:27

not allowed to own a pharmacy

13:30

because otherwise they could make a profit from

13:32

them. They would alter their

13:35

desire to tell you the truth and they might

13:37

lean towards trying to maximize their profit as a

13:40

conflict of interest. So

13:44

this actually is kind of well known.

13:46

It is due to a change in

13:48

pressure and it could be if it's

13:51

consistently happening on one side of your

13:53

head. It could be related to

13:55

a sinus being blocked. Is

13:57

it normally on just one side of your head? only

14:00

on one side of my head and it's mainly

14:04

in Sydney. I've tried to hove out everywhere

14:07

else and it's mainly in Sydney. That's why

14:09

I was curious. It could be the rate at

14:11

which they come down. It could be faster or slower.

14:13

They could be losing so many thousand feet per minute

14:15

faster or slower and I don't know. It could be

14:17

the cost of living and you just know

14:19

what you're in for when you

14:21

land. Exactly. David,

14:24

that's interesting but do you

14:27

find that chewing gum helps it or it's just...

14:29

It does in a way. It does in

14:31

a way but last

14:33

time when I landed Sydney the paint actually lasted

14:35

for an hour or two afterwards. I think it

14:37

hit the nail on the head

14:40

as well as in how quick they

14:42

drop in or slow they drop in

14:44

to land. I think that's got a

14:47

bearing on it too. You

14:50

have various sinuses in your head and

14:53

the word sinus refers to a

14:55

chamber that has only one

14:57

entrance and exit. So in the case

14:59

of say a coral it eats

15:02

through its mouth and then it poos it

15:04

out through its mouth. So there's a chamber

15:06

with only one way in and so you've

15:08

got various sinuses in your head and they

15:10

can get blocked and then there can be

15:12

pressure inside which can then cause pain and

15:14

the fact that it happens

15:17

over your eyebrow there is a sinus there. So

15:20

I would go and see a

15:22

GP and then get referred to an ENT

15:25

person. I think that'd be the right person

15:28

and I don't know

15:30

how you get access to that sinus

15:32

above your head easily. I don't know where

15:34

it drains to. I must drain.

15:36

Look I don't know. I've forgotten my basic

15:38

anatomy. Anyway that's my guess and if

15:40

there is an ENT person the number

15:42

to ring is 0439757. Triple five. Don't

15:44

get it right? He

15:48

did it! If

15:52

you use it you don't lose it. Oh my

15:54

gosh that is historic right here

15:56

on triple j. Jess

15:58

in Darwin. your question.

16:01

Morning Dr. Carl, I'm studying

16:04

cell biology. My question is

16:06

about cell survivability during reproduction

16:09

and would it be true to say

16:12

that the last born child is more

16:14

elite or more survivable? No

16:16

unfortunately. So the thing about, yeah, you're

16:19

the last born child. I'm the youngest.

16:22

There's a whole bunch of psychology in there,

16:24

I won't go into it. So what

16:27

happens is that you're getting a

16:29

random mix of half the mother's

16:31

DNA and half the father's DNA

16:35

on average but then how much of that

16:37

gets activated then that varies either 80-20 or

16:39

20-80 and so you can see a family

16:41

out for a walk and you look at

16:44

them and you go, oh my God, they

16:46

all look like him or her

16:48

and so that's the 80 or the 20 or the 20 or 80

16:52

but it is fairly random. Evolution

16:54

doesn't work that fast. Evolution

16:57

is not perfect. It only has to be

16:59

good enough and good enough means that you live

17:01

long enough to have babies which

17:03

was not the case for most of

17:05

human history. So for most of human

17:07

history going back 200,000 years we've

17:09

had 100 billion humans born and

17:12

the overwhelming majority of those died

17:14

before they were 20 and

17:16

most of them died before they

17:18

even hit puberty. Oh

17:21

wow, yeah. So it's only recently that we've

17:23

had a whole lot of people getting past that

17:25

and that was a combination of good

17:28

food with agriculture, combined with a

17:30

society sticking together and forming medicine

17:32

and then more recently antibiotics and

17:34

penicillin by itself increased life expectancy

17:37

by 15 years and

17:39

vaccines. So to say that the last born

17:41

child has the best DNA, I don't

17:44

think so but I really need an evolutionary

17:46

biologist to ring on 043975-0125. That's great because

17:48

I'm the oldest. I'm like, are

17:53

you the youngest or what? No.

17:56

Alright, thanks Jess. Hey,

17:59

we had David. who was asking about

18:01

the headaches that he would get on

18:03

descent, particularly in Sydney. Barry has texted

18:05

in saying, I was an airline pilot

18:08

based out of Sydney. Noise abatement procedures

18:10

requiring a shorter distance in which to

18:12

descend. So a quicker rate of pressure

18:14

in a quicker rate of pressure change

18:16

in the cabin. Oh, so

18:18

your option is that you either start to descend like

18:21

100 kilometres out or 20 kilometres out

18:24

or one kilometre out. And so you got

18:26

a really shallow glide path or a steep

18:28

one or a steep one. Yeah. The steepest

18:30

glide path I ever had was when we

18:33

were landing in Afghanistan and we were in

18:35

an Australian military airplane and we

18:37

started up at altitude and then suddenly we do

18:39

this really quick spiral and the pilot said, hey,

18:41

watch this. I was in the cockpit with the

18:43

pilot. He said, watch this. And suddenly we did

18:46

this straight down to the ground and that was

18:48

to avoid being hit by missiles from the people

18:50

who wanted to shoot missiles at us. Wow. So

18:52

there's none of this slow glide where they can

18:54

follow you. It's just sort of drop out of

18:56

the sky almost vertically and then land really quickly.

18:59

Well, that's the thing because David said that it

19:01

didn't happen to him when he was going to

19:03

Hobart and other places in Sydney. So maybe that

19:05

is the procedure. Yeah. So our airline pilot

19:07

said that for noise abatement, we've got to

19:09

have a relatively steep glide path in Sydney.

19:11

Oh my God, what a wonderful audience. Thank you,

19:14

Unknown Airline Pilot. We love you. Virginia

19:16

said, try taking a decongestant 20

19:18

minutes before landing and that could

19:20

potentially help as well. Why don't I

19:22

think of that? Thank you, Virginia. We've got

19:24

Tom in Wonga right here. Now, Tom,

19:27

you've got a question about bushfires. What's

19:29

up? Yeah, I have a

19:31

question relating to bushfires

19:33

and altitude. So

19:36

obviously there's less oxygen and altitude. So I want

19:38

to know, do bushfires burn

19:41

slower or with less ferocity at altitude

19:43

as opposed to, I guess, at

19:46

sea level? There's a bunch of

19:48

factors covering up the fact that I don't

19:50

know. The first one is that you've got

19:52

a tree line around, I think 11,000 feet.

19:55

They measure altitude in feet around the world

19:57

where you don't have no more trees anyhow.

19:59

They just... stop at that altitude, whatever it is, it's

20:01

around 11,000 feet, a couple of kilometers

20:03

up. Secondly, you tend to

20:06

have less density

20:09

of tree mass per

20:12

hectare. Then

20:14

you also have the temperature dropping with

20:17

altitude which is another factor involved

20:19

with the fire starting as opposed

20:21

to once it rages, 10 degrees

20:23

doesn't make any difference. And then

20:25

the moisture content can be different

20:28

in Alpine areas and

20:30

if it's drier, which I don't know it is,

20:33

but if it is drier, if it's lower, then

20:35

it'd be more likely to burn. And then of

20:37

course you can have the wind factors. So these

20:39

are various factors involved which I do not know

20:41

and there are fire experts and if you do

20:43

happen to know Ringo 439757555. Oh he's on it

20:45

now. Oh

20:48

yeah, forget this cognitive overload, overloading

20:50

mate, or offloading. But

20:52

I will just say that is our text line

20:54

number, don't try and call it, you will not

20:57

get through. We've got Josh Incoloundra here. Josh, what

20:59

do you want to know this morning? Dr. Josh. Good

21:01

morning doctors. My question is

21:03

about data and I don't mean data

21:05

like mobile data, like the data that

21:07

you get from the air so it

21:09

seems, but I mean like data

21:12

on a computer. So when we create like

21:14

say a Word document or an image of

21:16

JPEG or something and then it writes it

21:18

to the hard drive on the computer, is

21:21

that atoms, is that molecules,

21:23

what is actually being

21:25

written to a physical hard drive when we

21:28

have physical data? You've got

21:30

two main choices, changes in charge,

21:32

electrical charge, positive

21:35

or negative, or changes

21:37

in magnetic field, north

21:40

or south. And depending on whether you're

21:42

going one way or the other, it's

21:44

either a north or a one. So

21:47

you just got two choices, positive

21:49

or negative or north and south and one

21:51

of those corresponds to a one and the

21:53

other one corresponds to a north. And then

21:56

you put enough of these ones and norths

21:58

together and then you end up... with

22:00

all of the letters of the alphabet or

22:03

brightness scales and

22:05

color scales for a picture. So what

22:08

you're storing on a hard drive is

22:10

you're just merely flipping around the ones

22:12

and the noughts to be in different

22:14

states. So they're all ones or they're

22:16

all noughts or they're a mixture and

22:18

then you just vary that and

22:21

so you're not really adding atoms or

22:24

taking away atoms. You're just changing

22:26

magnetic fields or electrical charges. Now

22:30

we had a question about bushfires

22:33

at high altitude. Peter's

22:35

text students saying fire triangle for

22:37

fuel oxygen ignition. The bushfire behavior

22:40

determined by fuel condition and oxygen

22:42

availability. Wind obviously increases oxygen availability

22:45

and in extreme conditions dry out

22:47

the fuel. At altitude this

22:49

can be slower but not always so. Ah and

22:52

we have had bushfires that reach all

22:55

the way into the upper atmosphere. They're

22:57

called pyro cumulonimbus clouds and

22:59

they were first discovered from satellite photos in

23:01

the 70s but named in the 1990s and

23:04

we've had a couple of dozen

23:06

of them and one third of them happened in the

23:08

Australian bushfires in 2021 and they were powerful

23:11

enough to cool down the southern Pacific Ocean

23:13

and set off the triple lard in India

23:16

they think. Josh in Kalaujara also

23:18

had a question about data.

23:20

Ah and you reckon you got something

23:23

to add. What's the deal? Ah I

23:25

do have something on that. So there

23:27

was a professor of something now where

23:29

is it now. Found it. He worked

23:31

out that a free electron so

23:34

if you're not talking about the

23:36

magnetic fields we're talking about charges

23:38

okay so that's the other way

23:40

of storing information that a free

23:42

electron has a slightly

23:44

different energy state from an electron

23:47

that's married somewhere that's stuck and

23:49

then following that on if you've

23:51

got a four gigabyte drive that's

23:53

really full the difference in weight

23:55

is zero point and then you

23:57

write down 15 zeros and

24:00

then one of a gram. So

24:03

it's incredibly incredibly small

24:05

if it's real and everything has changed

24:07

from a free electron to a

24:09

bound electron or vice versa. So

24:13

data can have weight in that sense if

24:15

you're doing the E equals M C squared

24:17

thing. A vice on where energy is equivalent

24:19

to mass. We had a question

24:22

earlier about slit nails. Now Kylie you've

24:24

noticed something with your nails what's

24:26

going on? I've

24:29

noticed that every time

24:31

I cut my toenails outside

24:34

that the little ants come

24:36

along and take my clippings

24:38

and I've noticed many

24:40

many times and I've always wondered like

24:42

why do they do that? Like

24:45

do they eat it? I thought maybe

24:47

that then I noticed I try to

24:49

drag it back to their nest. I

24:52

have googled it and they said they say that

24:54

they like the keratin or something in it but

24:56

yeah I just thought I'd just thought I'd

24:58

ask Dr. Karl what who thought? They're

25:01

a very clever animal when together in

25:03

a group an individual ant isn't

25:05

that smart but when you put them into

25:07

a group they can build a community that

25:09

has social welfare

25:12

and baby care

25:14

and an army and farmers

25:18

and air conditioning and the

25:21

whole so

25:24

when you look at nails there's

25:26

two things there there's potential food

25:28

so they'd need to be able to break down the

25:31

keratin which is pretty hard but it's

25:33

not impossible and the other thing is

25:35

having a structural function so you could

25:37

use it as some sort of prop

25:39

that's small enough for them to be

25:41

carry but big enough to be useful.

25:43

Now they do have very complex social

25:45

structures so there'd be something going on

25:47

inside the nest and we'd

25:50

need an

25:53

entomologist to ring on 043977555 to

25:58

tell us the full story on on the

26:00

ant and the fingernails, but I reckon either one

26:02

of those as a guess, working from

26:05

first principles without any specific knowledge, what do you

26:07

kind of think is the answer? Well,

26:09

I, because I never see them eating it, like

26:11

they just seem to be dragging it back to

26:14

the hole, like that's the nest. And I was

26:16

thinking that when I googled it, that hasn't said

26:18

anything about that. I thought that's like what you

26:20

said, that they're taking it back to their nest

26:23

and using it in their, like you said,

26:25

you know, because they do have their

26:27

own little town underneath and

26:30

they're putting it in their, yeah, in

26:32

their nest and in their home. Is it structural?

26:34

Yeah, yeah. We may have an ant

26:36

site. Someone takes it in saying, ants take

26:39

keratin and other dense materials as an insulator

26:41

to keep their nests warm. Ah, wow.

26:43

So they've got that

26:45

structure of the nail that's keeping it all

26:48

locked in. Oh my God, I love

26:50

the concept of the circular economy that our

26:52

fingernails are keeping the ants happy. Yeah, keep

26:54

it up Kylie. Yeah, that's what I saw.

26:56

I know every time, every time, but thank

26:59

you. Yeah, that's what I thought. You're keeping

27:01

the ants warm. We've got Anthony from Bumburi

27:03

here. Dr. Anthony, you got a question about

27:05

exercise? Ah, yeah.

27:07

Um, I just, a question

27:09

about exercise. Like when I exercise in the

27:12

heat, um, does it

27:14

change how I feel the

27:16

temperature when I'm not exercising or not?

27:19

Okay. The first thing is to make sure

27:21

that you're properly hydrated and I'm assuming that

27:23

we've got that out of the way that

27:26

you have enough water afterwards and then you

27:28

go through a thing called acclimatization. And so

27:30

people who are going to be doing some

27:33

sort of sports activity in an area

27:35

that's different from where they normally exercise,

27:37

so it might be at high altitude

27:39

or high humidity or higher or lower

27:41

temperature, they will then go there to

27:43

acclimatize and in most cases they

27:46

end up with better heat

27:48

resistance. So the

27:51

first time they do exercise, they feel the

27:53

heat for a long time afterwards. In some

27:55

cases, and we don't know why, a small

27:57

minority of people will end up feeling worse.

28:00

after doing their exercise and it never seems

28:02

to get better. And the only way they

28:04

can get better is by going back to

28:06

their normal environment, which is kind of sucks

28:08

if you move to Darwin and you like

28:10

running and you think, oh

28:13

God, I'm going to feel terrible afterwards. But

28:15

in most cases, you actually do acclimatize and

28:18

you adjust better and you compensate better. Is

28:20

that what you found? Yeah, yeah, pretty

28:22

well. Awesome. Thanks,

28:25

Anthony. And we've got Eden in Phillip Island.

28:27

Eden, what do you want to ask Carl? I

28:31

have a question regarding

28:34

the universe. They say

28:36

the universe is expanding,

28:38

but what is actually expanding?

28:40

Is it the distance between

28:43

planets, solar systems, galaxies, or

28:46

is it down on the atomic level? Ah,

28:49

it's below the atomic level,

28:51

down at the Planck level.

28:53

So you know how they

28:55

talk about space having three

28:57

dimensions, like backwards and

28:59

forwards and left and right and

29:01

up and down? Yes. Okay. So

29:05

we never really knew

29:07

whether time was part

29:09

of that triple, because

29:12

the thing about time as a dimension

29:14

is we only see it going forward,

29:16

we never see it going backward. So

29:18

it's different from those other three dimensions.

29:20

And it was Einstein in

29:23

1905 who mathematically showed that

29:25

time is married to space.

29:27

So now we talk about space-time. And

29:31

he teamed up with a really good mathematician called

29:33

Minkowski in 1908, and

29:36

between them they showed that time and space are

29:39

one thing. They're an entity. Now,

29:41

let's just ignore the fact that

29:44

there's another eight dimensions out there. Let's

29:46

just completely forget that. So we've got

29:48

these four dimensions, space-time. Think about it

29:50

like dough that you're putting into an

29:52

oven to turn into a cake. It's

29:54

this big, and after a while it's

29:56

going to be bigger. put

30:00

some raisins in there. And

30:02

the raisins, when

30:05

you start off, they're fairly close together,

30:07

but after you've baked them, they're further

30:09

apart. They haven't burrowed through the dough,

30:11

but the expanding dough has carried it

30:14

with them. In the same way, what's

30:16

expanding in space is the actual fabric

30:18

of space-time. It's not as though Earth

30:22

is sort of moving further away

30:24

from the Sun, but rather the

30:26

whole fabric of space-time is expanding.

30:29

And there is this very

30:31

weak outward expansion, and that's

30:33

massively overcome by the weak strong

30:36

gravity inside the Solar System. So

30:38

it's the space between the galaxies

30:41

that's expanding. Inside the galaxy,

30:43

the gravity is strong enough to overcome

30:45

that weak expansion, but between the galaxies,

30:47

there's a lot of room, like millions

30:50

of light-years, and so there's a

30:52

fabric of space-time expanding, carrying the

30:54

galaxies with them, like the dough

30:56

carries the current in the cake

30:59

mixture. Is that making sense? Thank

31:01

you. That's awesome. Yeah, that makes

31:03

perfect sense. Grant

31:05

from Wagga Wagga. What happened to you a

31:07

few years ago? Yeah, guys. So

31:10

a few years ago, my mate and I were

31:12

fishing during an electrical storm. We were in a

31:14

fiberglass boat, and we actually got struck by lightning

31:16

while we were standing out of the dam. It

31:19

threw us to the floor of the boat,

31:21

and my mate's got metal in his knee

31:24

from previous surgery, and he felt it draw through to his

31:26

knee. But we're just wondering if being in

31:28

a tinny would have made much difference if it would have earthed

31:30

and it would have been a different outcome, or

31:33

what happened now? How big

31:35

was the boat? Like one meter or five meters

31:37

or ten meters or a hundred? Probably like a

31:39

six-meter boat. Oh,

31:42

six meters. So a reasonable size. Yeah, we

31:44

were standing up in the boat. It was

31:47

raining. The floor was wet, and

31:49

we were side by side pretty much. So we

31:51

put our graphite rods down. But

31:54

yeah, just like we both felt it hit us in the

31:56

head, and we got thrown to the floor of the boat,

31:59

and that was it. like we just stood up and

32:01

couldn't believe what happened. My God. As

32:04

it was building up, was

32:06

there like the flash, then

32:08

the bang, and then the time difference was

32:10

getting smaller and smaller as it came to

32:13

you? We could see lightning

32:15

striking all around and we sort of knew we weren't in

32:17

a safe spot. And then the

32:20

loudest bang I've ever heard and the brightest white light

32:22

and next thing you know we're on the ground. Really?

32:26

You could hear the filter coming and

32:28

then suddenly there's a combination simultaneously, virtually

32:30

of the light and the sound and

32:32

the next thing you know you were

32:34

both thrown to the floor of the

32:36

boat and you had no choice in

32:38

the matter, you just got thrown. Yeah,

32:40

I was just knocked down. Right, okay

32:42

so almost certainly what was happening was

32:44

that you're standing upright because you've got

32:46

a brain and you're running your muscles

32:49

and you're keeping yourself in dynamic equilibrium.

32:51

Then the lightning bolt hits and how

32:54

high was the side of the boat above the

32:56

water? Was it like half a meter or five meters?

32:59

Probably half a meter, it's

33:01

more of a best style fishing boat so

33:03

fairly low to the water. Okay so the

33:05

side of the boat is wet with water,

33:07

it makes no difference whether it's made of

33:10

metal or fiberglass because there's enough water

33:12

on the outside for the lightning to run through it

33:14

so it's not going to make any difference. So just

33:16

land on you guys because you're the highest thing around

33:19

and then you lost your muscular

33:21

coordination as all of your electrical

33:23

connections in your nerves got switched

33:26

on and then switched off again and

33:28

you lost your delicate coordination so you just go thumb

33:30

to the ground or it could have been that you

33:32

had the muscles contract so you got thrown to the

33:34

ground. Did you have any long term injury? No,

33:37

we kept fishing after that. Oh

33:40

my God, you are so lucky there are

33:42

so many cases of people who have been

33:44

hit by lightning and who have long term

33:46

injuries and you had none. Look I wouldn't

33:49

have made any difference, lightning hitting fiberglass or

33:52

metal because the water would have carried the electricity

33:54

anyway but I'm so glad you didn't get hurt.

33:56

We've got Beau in Werribee here. Beau you've

33:58

got a hypothetical, what's up? Dr. Butler.

34:01

Yeah. So, I'm just wondering if

34:03

the Earth was to stop spinning and stop orbiting,

34:05

how long would it take for it to like,

34:07

pick up its orbit and pick up its spin

34:09

again? Did it even be habitable, if possible at

34:11

all? Newton's First Law

34:13

tells us that an object will keep on

34:15

doing what it's doing and pillar force acts

34:18

on it. And so, if

34:20

it stops and there's no

34:22

other force acting on it, it won't start

34:24

up again. Unless there's a bit of spin

34:27

from stuff inside the Earth, internal rotation, the

34:29

core rotations rotates it one day

34:31

different from the surface per year. So, it's

34:33

got a different rotation rate. So, if the

34:35

surface stops and the inside keeps rotating, it

34:38

might spin the surface up again. But

34:40

then in the orbit around the sun, if it

34:42

stops in its 30 kilometer per second

34:45

motion, it will just fall into

34:47

the sun. Is that what you're asking? Yeah,

34:50

pretty much. Yeah. So, Newton's

34:52

First Law answers that, which is incredibly deep,

34:54

and he came up with it during the

34:56

plague in the 1660s. And

34:59

we've got Wes, impressed and to finish. Now,

35:01

Wes, we're just talking about thunder and lightning.

35:03

What did you see yesterday? Yeah,

35:05

hey guys. It was about

35:07

a week ago and it was the exact

35:11

polar opposite to your previous

35:14

caller. I was at the dog

35:16

park and we were watching these

35:18

clouds in the distance and there were

35:20

big, white, fluffy clouds. And

35:22

there was heaps of fork lightning in the clouds, but there

35:25

was no sound. How far away

35:27

was it? I'd

35:29

say at least probably 50 or 60,

35:31

70 kilometers away. And

35:34

it was in two spots too. I had it in

35:37

out east and I was looking also north

35:40

and there were two clusters of clouds,

35:42

big, huge clouds and no

35:44

other clouds in the sky. So that's the

35:46

best way I can sort of describe it,

35:48

I guess. Okay, so the sound travels at

35:51

one kilometer every three seconds. And if the

35:53

wind is going against you, if it's going

35:55

from you to the clouds, then it'll be

35:57

pushing the sound backwards. the

36:00

sound wasn't strong enough to cover that

36:02

distance of 10-50 kilometres. That's

36:05

a guess. As you mentioned, sorry, the lightning

36:08

itself, the fork lightning within clouds

36:10

wasn't touching the ground. It was

36:13

literally just staying up

36:15

in the air. And I've never

36:17

seen something like that before. Oh, you're very

36:19

lucky because there's one and a half billion

36:21

lightning bolts each year and 90% of them

36:23

happen in the clouds and you don't normally

36:25

see it and you're very lucky to see

36:27

that event is very common but hard to

36:29

see. You're a lucky person. Cool.

36:33

Thanks so much for listening to this episode

36:36

of Science with Dr. Carl. There's plenty more

36:38

for you to tuck into via the podcast

36:40

feed. Make sure you like, subscribe, see the

36:42

first to know when a new episode drops.

36:45

This episode was produced by Lou Hill and

36:47

Sean Hatsey. My name is Lucy

36:49

Smith. I'll catch you next week. Bye. Dave

36:51

Marchese here from the Triple J Hack

36:54

Team. Hey, if you love Dr. Carl's

36:56

podcast like I do, you might enjoy

36:58

the Hack Podcast as well. Each

37:00

day we bring you the news that matters

37:03

to you from the latest science on climate

37:05

change to what's happening in politics and news

37:07

around the world. The Hack Podcast. It's your

37:09

daily fix of the news you need to

37:12

know. Get it wherever you're listening now.