0:00:02 > 0:00:04BOTH: We are Dr Chris and Dr Xand van Tulleken.
0:00:04 > 0:00:07- And we're tracking down the most awesome...- Incredible...
0:00:07 > 0:00:12BOTH: And epic things in the universe!
0:00:21 > 0:00:24BOTH: Come with us and discover unbelievable things
0:00:24 > 0:00:27that will blow your mind!
0:00:29 > 0:00:31Blow Your Mind will be bringing you all the top experts
0:00:31 > 0:00:33in unbelievable stuff.
0:00:33 > 0:00:37From icebergs to elephants, spaceships to sharks.
0:00:37 > 0:00:41And this week, it's all about amazing animals.
0:00:41 > 0:00:44So, hold on to your brains, here's what's coming up...
0:00:44 > 0:00:47Today, we're investigating the smelly secrets of the animal
0:00:47 > 0:00:49we know best of all, dogs.
0:00:49 > 0:00:54And testing them against their ancient ancestors, wolves.
0:00:54 > 0:00:59Coming up later, it's dogs versus wolves in a battle of the senses.
0:01:01 > 0:01:02HOWLING
0:01:02 > 0:01:05- What are you doing? - Sorry about that.
0:01:05 > 0:01:07I was just practising my howling.
0:01:07 > 0:01:09Wolves howl for lots of different reasons,
0:01:09 > 0:01:12but one of the reasons is to bring the pack together.
0:01:12 > 0:01:16- Like when we have a sing-along. - Yes...exactly.
0:01:16 > 0:01:18So, if dogs are descended from wolves,
0:01:18 > 0:01:20- is that why they sometimes howl?- Yes.
0:01:20 > 0:01:24Dogs have actually been bred from wolves over thousands of years,
0:01:24 > 0:01:26so they're now quite different animals.
0:01:26 > 0:01:28That is what we'll talk about today.
0:01:28 > 0:01:30Ladies and gentlemen, boys and girls,
0:01:30 > 0:01:34I bring you the main competition - dog versus wolf.
0:01:34 > 0:01:36Awwwwww!
0:01:36 > 0:01:39But before we do that, let's find out what happened
0:01:39 > 0:01:42when Chris Packham went all the way to Indiana, USA,
0:01:42 > 0:01:45to meet some howling wolves, face to face.
0:01:45 > 0:01:48- Can I howl?- Yes.- Awwwwww!
0:01:48 > 0:01:51HOWLING
0:01:57 > 0:01:58'Wolves are fascinating,
0:01:58 > 0:02:01'because, biologically, they're the same as dogs.
0:02:04 > 0:02:09'Around 10,000 years ago, humans began domesticating some wolves.
0:02:09 > 0:02:12'And, over time, they created dogs.
0:02:12 > 0:02:15'Now, wolves haven't changed much in that time.
0:02:16 > 0:02:18'Dogs, on the other hand,
0:02:18 > 0:02:21'have evolved into an astonishing variety of breeds.
0:02:21 > 0:02:25'They look very different to wolves.
0:02:25 > 0:02:28'To give us some insight, we're going to test dogs
0:02:28 > 0:02:31'and wolves in a battle of the senses.
0:02:31 > 0:02:34'So, first, I want to establish the sensory abilities
0:02:34 > 0:02:39'these two animals share, starting with smell.'
0:02:39 > 0:02:42So, what's Chris Packham going to use to tempt the wolves?
0:02:42 > 0:02:44Three pigs? Little Red Riding Hood?
0:02:44 > 0:02:46No, Chris, he's going to use this.
0:02:46 > 0:02:50The finest, most expensive perfume in the world.
0:02:50 > 0:02:53That's my perfume. Hey, that's really expensive.
0:02:53 > 0:02:55Actually, this is really expensive perfume.
0:02:55 > 0:02:59And what's amazing is what happens when Chris Packham sprays it
0:02:59 > 0:03:01on the grass in Wolf Park, Indiana.
0:03:01 > 0:03:03- What? How did he get hold of my perfume?- Watch this.
0:03:03 > 0:03:08This couple of wolves down here, they're about 60 metres away.
0:03:08 > 0:03:10And I'm going to test that sense of smell.
0:03:10 > 0:03:12They've got expensive taste,
0:03:12 > 0:03:15so I'm just going to sneak down here...
0:03:17 > 0:03:19..put some of this on the grass...
0:03:20 > 0:03:22..and see what happens.
0:03:29 > 0:03:32Ah, there goes a tenner, at least. Let's see what happens.
0:03:32 > 0:03:34'Now, Chris isn't just interested
0:03:34 > 0:03:38'in whether the wolves can pick up the scent from so far away,
0:03:38 > 0:03:42'he's also interested in what happens when they smell it.'
0:03:44 > 0:03:46'Oh, here he comes.
0:03:49 > 0:03:51'And he's smelling it.
0:03:52 > 0:03:55'Whoa! He loves it!'
0:03:56 > 0:03:58This is what we call scent rolling.
0:03:58 > 0:04:01I'm afraid to say that many of you have probably seen your dogs
0:04:01 > 0:04:05doing this in less pleasant things than expensive perfume.
0:04:08 > 0:04:10Ha-ha-ha! That's brilliant, isn't it?
0:04:10 > 0:04:12So, my dog does this the whole time.
0:04:12 > 0:04:15He loves to go to the park and roll around in anything stinky,
0:04:15 > 0:04:17especially fox poo.
0:04:17 > 0:04:19Why do they both do the same thing?
0:04:19 > 0:04:22Well, no-one really knows, but one theory is that
0:04:22 > 0:04:25when a pack member finds a smell, they roll around in it
0:04:25 > 0:04:28and then they can bring that stinky message back to the pack.
0:04:28 > 0:04:31It's like they're communicating, using smell.
0:04:31 > 0:04:32There's that clever nose again.
0:04:32 > 0:04:35So, dogs and wolves do have some similarities.
0:04:35 > 0:04:37But what we're interested in now is the differences.
0:04:37 > 0:04:40There's a place in the USA called Dognition,
0:04:40 > 0:04:42that does lots of cool experiments
0:04:42 > 0:04:44on dogs and their owners, to find out more.
0:04:44 > 0:04:47- That sounds really fun. - It is. Check it out.
0:04:51 > 0:04:56'Any dog owner knows that dogs watch us closely with their eyes.
0:04:56 > 0:04:59'So, how important is vision to dogs?
0:05:03 > 0:05:06'Dr Brian Hare is chief scientific officer.
0:05:06 > 0:05:09'He has recruited dog owners from across the USA
0:05:09 > 0:05:11'to carry out some simple tests
0:05:11 > 0:05:14'that show how dogs use visual information.'
0:05:16 > 0:05:20And now watch where her gaze goes. Right at me. Stay!
0:05:20 > 0:05:23So, what we've got here is a very simple experiment.
0:05:23 > 0:05:25We've got two people, two cups.
0:05:25 > 0:05:28We've hidden food in both cups and we have a dog, of course.
0:05:28 > 0:05:31And all I'm going to do is gesture to one of the two cups.
0:05:31 > 0:05:34Question is, does the dog go where I gesture,
0:05:34 > 0:05:35or to the other cup?
0:05:35 > 0:05:37It can't be that she's just using her smell
0:05:37 > 0:05:41when she makes her decision, because there's food in both cups.
0:05:41 > 0:05:42'Now, both cups smell equally tasty,
0:05:42 > 0:05:46'so she can't just be using her sense of smell to make her decision.
0:05:46 > 0:05:50- 'There's only one reason for her to choose between the cups.'- You ready?
0:05:52 > 0:05:56'This. It's the visual pointing signal that Brian is giving her.'
0:05:58 > 0:06:00Good job! All right, there was one here, too.
0:06:00 > 0:06:03All right, so, she did use my gesture there.
0:06:03 > 0:06:06Sometimes, I point to the right, sometimes, to the left.
0:06:06 > 0:06:08Let's do it again. It could be chance.
0:06:12 > 0:06:15(Hey.) OK.
0:06:17 > 0:06:18(All right!)
0:06:18 > 0:06:22So, what we've seen is that she really relies on my visual gestures.
0:06:22 > 0:06:25She's not relying on her nose. If I'm there and tell her something,
0:06:25 > 0:06:30she's much more happy to use that information than rely on her nose.
0:06:32 > 0:06:36'Most dog owners know dogs happily follow hand signals from them.
0:06:36 > 0:06:39'But we also know dogs have amazing noses
0:06:39 > 0:06:41'and a brilliant sense of smell.
0:06:41 > 0:06:44'So, which sense do dogs trust the most?
0:06:44 > 0:06:48'Is it their sense of sight or their sense of smell?'
0:06:49 > 0:06:53I think sight. No, smell. No, definitely sight.
0:06:53 > 0:06:56- Maybe smell. - Chris, relax. Let's find out.
0:06:59 > 0:07:03'To find out, Brian is going to give Dexter the dog two opposing signals,
0:07:03 > 0:07:07'putting his sense of sight in conflict with his sense of smell.'
0:07:07 > 0:07:09So, we're going to actually show Dexter
0:07:09 > 0:07:13where we're going to hide the food, so he can remember where he saw it.
0:07:13 > 0:07:16But then, we're going to close his eyes and shift where it's hidden.
0:07:16 > 0:07:18We'll move it to the other location,
0:07:18 > 0:07:20so he could potentially smell where it is.
0:07:20 > 0:07:23The question is, does he use what he saw to find the food
0:07:23 > 0:07:25or does he rely on his nose?
0:07:25 > 0:07:27So, let's see what he does.
0:07:27 > 0:07:30All right, Dexter?
0:07:30 > 0:07:33Oh, look at that face! Oh! You're killing me.
0:07:33 > 0:07:35All right, Dexter, are you ready, buddy?
0:07:35 > 0:07:38OK, that's where it's going to be.
0:07:38 > 0:07:41'This time, there's only food under one cup.'
0:07:41 > 0:07:43OK, close your eyes.
0:07:44 > 0:07:46'And without Dexter seeing,
0:07:46 > 0:07:48'Brian's now moving that food to the other cup.
0:07:50 > 0:07:52'Poor Dexter knows where he SAW it hidden,
0:07:52 > 0:07:55'but can smell it in a different place.
0:07:55 > 0:07:57'Does he trust his eyes, or follow his nose?'
0:07:57 > 0:07:59OK, Dexter, find it!
0:08:01 > 0:08:05Oh! What happened? It's a trick! It's over here.
0:08:05 > 0:08:08It was a trick! Are you ready, Dexter?
0:08:08 > 0:08:12OK, we're going to put it over here. Here it is. Now, close your eyes.
0:08:16 > 0:08:18OK, Dexter, go and get it!
0:08:18 > 0:08:21You remembered! Except for, it's not there any more!
0:08:21 > 0:08:24'Again and again, Dexter, like most dogs,
0:08:24 > 0:08:27'goes not to where he can smell the food,
0:08:27 > 0:08:29'but where he saw the food.'
0:08:29 > 0:08:31Aw!
0:08:32 > 0:08:34'Dognition have a website with things people can try
0:08:34 > 0:08:37'with their dogs, to join in with this science experiment
0:08:37 > 0:08:39'and learn about dogs, at the same time.'
0:08:39 > 0:08:43What if you want to find out more about your identical twin brother?
0:08:43 > 0:08:47Well, I've put a sweet under one of these cups, but which one is it?
0:08:47 > 0:08:48Can you guess?
0:08:55 > 0:08:57How did he do that?
0:08:57 > 0:08:59Back to the dogs and wolves. We want to find out if wolves
0:08:59 > 0:09:02also use their sense of sight as much as their sense of smell.
0:09:02 > 0:09:04Chris Packham went to find out.
0:09:07 > 0:09:11'Back at Wolf Park, we're going to test them.
0:09:12 > 0:09:15'Kathryn Lord, from the University of Massachusetts,
0:09:15 > 0:09:17'reared this group of wolves from birth.
0:09:17 > 0:09:20'And they're certainly familiar with humans.'
0:09:20 > 0:09:22I know, I know.
0:09:22 > 0:09:25I'll stand up for a second, because you're getting a little excited.
0:09:25 > 0:09:29'This grey wolf, Fi, can understand certain types of information
0:09:29 > 0:09:31'that a wild wolf wouldn't.'
0:09:31 > 0:09:34- Get up! - HOWLING
0:09:34 > 0:09:36'She comes when her name is called.'
0:09:36 > 0:09:38Fi?
0:09:38 > 0:09:42'And remarkably, Fi can also follow Kathryn's pointing.
0:09:42 > 0:09:48'She's just as capable as any dog of understanding what it means.'
0:09:48 > 0:09:49(Hey.)
0:09:49 > 0:09:54'We've seen that dogs trust this visual signal above smell.
0:09:55 > 0:09:57'So, is this also true of wolves?
0:09:59 > 0:10:02'To find out, we're going to repeat the finger-pointing test
0:10:02 > 0:10:06'several times, just as we did with the dogs.
0:10:06 > 0:10:09- 'With a snack under each can.'- Fi?
0:10:11 > 0:10:17'So, will Fi the wolf respond like a dog to a series of finger points?'
0:10:18 > 0:10:21- She didn't appear to look, did she? - She just went for the cheese.
0:10:21 > 0:10:25'Fi has quickly learned that, in this experiment,
0:10:25 > 0:10:29'the visual signal is irrelevant for finding the food.
0:10:29 > 0:10:34'Instead, she chooses to follow her nose.'
0:10:34 > 0:10:36So, even though Fi the wolf is looking at Kathryn,
0:10:36 > 0:10:40she chooses to ignore the visual command of the pointing
0:10:40 > 0:10:43- and trust her sense of smell about where the food is.- Exactly.
0:10:43 > 0:10:46And here's why Kathryn thinks this is happening.
0:10:46 > 0:10:50The reason she's ignoring me is because she's perfectly capable
0:10:50 > 0:10:52of solving the problem without my help,
0:10:52 > 0:10:54so she doesn't need to pay attention to me.
0:10:56 > 0:11:00'So, seeing seems to be less important for wolves than smelling.
0:11:00 > 0:11:04'Kathryn believes she may have discovered why.
0:11:05 > 0:11:10'It's all about what happens in the first few weeks of life.
0:11:10 > 0:11:15You investigated this by raising wolf cubs from that very young age
0:11:15 > 0:11:18- and contrasting their behaviour with dogs.- I did, yeah.
0:11:18 > 0:11:21I actually hand-raised both wolves and dogs.
0:11:21 > 0:11:22The wolf pups are great.
0:11:22 > 0:11:25We get them at about ten days of age.
0:11:25 > 0:11:28So, at that point, they can't see, they can't hear and they can't smell
0:11:28 > 0:11:31and they can't really walk. They're just little puddles of fur.
0:11:31 > 0:11:34'But as her wolf cubs developed,
0:11:34 > 0:11:37'Kathryn observed something amazing.
0:11:38 > 0:11:41'There's a brief window of time, soon after they're born,
0:11:41 > 0:11:45'when the senses of both dogs and wolves are set for life.
0:11:47 > 0:11:50'For wolves, this starts at just two weeks' old.
0:11:52 > 0:11:55'At this stage, none of their other senses are fully developed,
0:11:55 > 0:11:56'apart from their sense of smell.
0:11:56 > 0:12:00'So, they can only understand their world through their nose.
0:12:03 > 0:12:05'But dogs' senses are set at four weeks' old.
0:12:05 > 0:12:08'This is a small, but important, difference.
0:12:08 > 0:12:12'Because by then, dogs have developed all their senses,
0:12:12 > 0:12:13'not just smell.
0:12:16 > 0:12:20'So wolves have to trust their sense of smell when they're very young
0:12:20 > 0:12:24'because they haven't fully learnt how to see, hear or taste things,
0:12:24 > 0:12:27'whereas dogs develop all their sense together
0:12:27 > 0:12:30'and use them all to discover the world around them.
0:12:30 > 0:12:33'The difference in how they use their senses
0:12:33 > 0:12:37'has helped make dogs and wolves very different animals.'
0:12:37 > 0:12:40So, although dogs and wolves do have things in common,
0:12:40 > 0:12:42there are actually big differences,
0:12:42 > 0:12:44because dogs have evolved natural behaviours,
0:12:44 > 0:12:47which allow them to live happily alongside us humans.
0:12:47 > 0:12:50That's why they're called "man's best friend".
0:12:50 > 0:12:52If you think about having a wolf as your best mate,
0:12:52 > 0:12:55it'd be really difficult, because they'd be constantly
0:12:55 > 0:12:57eating your friends and dressing up as Grandma.
0:12:57 > 0:12:58That's exactly right, Chris.
0:12:58 > 0:13:03I did think the way they reacted to those smells was awesome.
0:13:03 > 0:13:06You might say it was o-u-u-utstanding!
0:13:06 > 0:13:07You might say that.
0:13:07 > 0:13:11Well, if you thought that was outstanding, join us next time...
0:13:11 > 0:13:14Because Blow Your Mind is going undercover.
0:13:14 > 0:13:18We're using GPS trackers and secret surveillance cameras on cats.
0:13:18 > 0:13:20- On cats?- On cats!
0:13:20 > 0:13:23- So join us next time, to... - BOTH: Blow your mind!