0:00:02 > 0:00:04# Marauding mice and walls of ice
0:00:04 > 0:00:06- # And sharks on a golfing spree - Argh!
0:00:06 > 0:00:08# Cicada swarms and Martian storms
0:00:08 > 0:00:11- # And fish walking out of the sea - Really?
0:00:11 > 0:00:13# Elks in trees and foaming seas
0:00:13 > 0:00:15- # And giant mayfly moths - Huh?
0:00:15 > 0:00:17# Zombie snails and friendly whales
0:00:17 > 0:00:19- # And completely frozen frogs - You what?
0:00:19 > 0:00:22# They're wild and weird, wild and weird
0:00:22 > 0:00:23# Really really wild and really really weird
0:00:23 > 0:00:26# They're wild and weird, wild and weird
0:00:26 > 0:00:28# They're really really wild
0:00:28 > 0:00:29# They're really really wild and weird. #
0:00:29 > 0:00:33On today's show, some clever critters.
0:00:33 > 0:00:34Dogs on a train.
0:00:35 > 0:00:38A crow on a zebra crossing.
0:00:38 > 0:00:41And a real-life fish out of water.
0:01:00 > 0:01:02What are you doing?
0:01:02 > 0:01:05- Inventing. - Ooh, inventing what?
0:01:05 > 0:01:06This.
0:01:06 > 0:01:09Behold, the Brain Booster 3,000.
0:01:12 > 0:01:14It's designed to rewire my neural system,
0:01:14 > 0:01:18exponentially increasing the efficiency of my synaptic pathways.
0:01:18 > 0:01:19Eh?
0:01:19 > 0:01:21- Makes me more cleverer.- Oh.- Yeah.
0:01:21 > 0:01:23That reminds me, actually.
0:01:23 > 0:01:26I've got some clips about brainy animals for us to watch.
0:01:26 > 0:01:27- Are you coming?- No, I can't.
0:01:27 > 0:01:28I've got to find the control interface
0:01:28 > 0:01:30because if it's not configured correctly
0:01:30 > 0:01:32it could have catastrophic consequences.
0:01:32 > 0:01:35- OK.- Now, where did I PUUUUT it?
0:01:35 > 0:01:38- Oh.- Naaaaah! Naomi. - That's funny, it's not working.
0:01:38 > 0:01:40It's cos it's... Waaah!
0:01:40 > 0:01:43Aaaargh!
0:01:43 > 0:01:44Waaah!
0:01:46 > 0:01:48Aaaaaah!
0:01:48 > 0:01:50Oh. Oh, whoops.
0:01:50 > 0:01:52Oh, look, I was using the wrong...
0:01:53 > 0:01:54Tim?
0:01:56 > 0:01:57Oh.
0:01:59 > 0:02:02We start with a shaggy dog story from Russia.
0:02:02 > 0:02:04The Moscow Metro is one of the busiest underground train
0:02:04 > 0:02:08systems in the world, carrying millions of passengers every day.
0:02:10 > 0:02:14Don't be ridiculous. There is no such thing as underground trains.
0:02:14 > 0:02:18Next you're going to be telling me there's boats that travel underwater.
0:02:18 > 0:02:20Do you mean like a submarine?
0:02:20 > 0:02:24Oh, yeah, good one. Submarine. Go on, carry on.
0:02:25 > 0:02:28But, in amongst the commuters, making their way through
0:02:28 > 0:02:33the trains and tunnels are a remarkable group of city slickers.
0:02:33 > 0:02:35- Dogs.- That's not clever.
0:02:35 > 0:02:37People take their dogs on the train all the time.
0:02:37 > 0:02:40Ah, but these dogs don't have any owners
0:02:40 > 0:02:42and yet every morning they join the commute,
0:02:42 > 0:02:46queuing for trains and sharing seats with the passengers.
0:02:46 > 0:02:48How do they hold the tickets?
0:02:48 > 0:02:50I don't think they have tickets, Tim.
0:02:50 > 0:02:54Yes, of course. Season passes. Very clever. Very clever.
0:02:55 > 0:02:58Expert Suzanne MacDonald has been studying how animals adapt
0:02:58 > 0:03:00to city life.
0:03:00 > 0:03:03It only makes sense for dogs to do this if they're feral.
0:03:03 > 0:03:05If they don't have owners. So it's clear they must be homeless dogs.
0:03:05 > 0:03:08I don't think you would see this kind of behaviour in a city
0:03:08 > 0:03:11where there aren't large populations of feral dogs.
0:03:12 > 0:03:14And Moscow certainly has that.
0:03:14 > 0:03:18Around 35,000 stray dogs live on the city streets.
0:03:18 > 0:03:22It's a tough life, where competition for food and shelter is fierce.
0:03:22 > 0:03:26But how exactly have these stray hounds ended up underground?
0:03:27 > 0:03:30Well, they just take the escalator, don't they, like everybody else.
0:03:30 > 0:03:33No, I mean why are they doing it?
0:03:33 > 0:03:36Oh, I don't know. I'm not an expert. Ask Suzanne.
0:03:36 > 0:03:40If you were a dog and you saw a human who'd give you food
0:03:40 > 0:03:43and, one day, you followed the human and the human went down into a train
0:03:43 > 0:03:45and the human petted you and told you how great you were,
0:03:45 > 0:03:47and everybody on the train was nice to you
0:03:47 > 0:03:50and then, when you got off the train, you followed the humans,
0:03:50 > 0:03:51somebody fed you, you might say
0:03:51 > 0:03:54the train is a good place and so you might do that again.
0:03:54 > 0:03:57Dogs are very fast learners, so I think could spread
0:03:57 > 0:04:00through a population of stray dogs really quickly.
0:04:00 > 0:04:02And it isn't just dogs who go looking for food on public
0:04:02 > 0:04:04transport either.
0:04:04 > 0:04:06Other animals are also riding the rails,
0:04:06 > 0:04:09whether it's monkeys in India,
0:04:09 > 0:04:11or a pigeon right here in the UK.
0:04:13 > 0:04:17OK, but that's still not being clever like us humans, is it?
0:04:17 > 0:04:19They're just following food.
0:04:19 > 0:04:22I mean, us humans, we are sophisticated, intelligent...
0:04:22 > 0:04:23Fetch.
0:04:25 > 0:04:27It's not just following food.
0:04:27 > 0:04:30The really clever part is that some of the dogs are getting on
0:04:30 > 0:04:35and off the train at the same stops at the same times every day.
0:04:35 > 0:04:39They're actually using the Metro to make a regular commute to work.
0:04:39 > 0:04:41They're coming from a place where they sleep,
0:04:41 > 0:04:43which would be on the outskirts of the city.
0:04:43 > 0:04:45They probably go where it's quiet at night.
0:04:45 > 0:04:48They may go somewhere where they can actually sleep with other dogs
0:04:48 > 0:04:50and then in the daytime they would go downtown
0:04:50 > 0:04:53where they can hit up tourists for food and look sad-eyed
0:04:53 > 0:04:55and get some snacks and, you know, that sort of thing.
0:04:55 > 0:04:58So, it's sort of like they go from the suburbs at night
0:04:58 > 0:05:01to their day jobs downtown.
0:05:01 > 0:05:03- That simply can't be true. - Why?
0:05:03 > 0:05:05Well, how would they know which stop was which?
0:05:05 > 0:05:08It's not like they can read a Tube map like me, is it?
0:05:08 > 0:05:10It's the other way up, Tim.
0:05:15 > 0:05:17You are right, though.
0:05:17 > 0:05:21Dogs don't read maps but these stray animals have the same instincts
0:05:21 > 0:05:23and senses as wild dogs like wolves,
0:05:23 > 0:05:28including a sense of smell 10,000 times better than our own.
0:05:28 > 0:05:32So, they can easily identify each individual stop just by smell alone,
0:05:32 > 0:05:36which is how they know where to get on and where to get off.
0:05:36 > 0:05:38Sniff-sniff. This is easy.
0:05:40 > 0:05:42Ooh!
0:05:42 > 0:05:44So whatever way you look at it,
0:05:44 > 0:05:46you have to say that these rail-riding pooches
0:05:46 > 0:05:48really are top dogs.
0:05:50 > 0:05:52The District Line at this time going to be absolutely rammoed,
0:05:52 > 0:05:54so if I was you I'd get on Central Line,
0:05:54 > 0:05:57- then you'll need to change at Oxford Cir...- What are you doing?
0:05:57 > 0:06:01Just giving Fido directions to the shop. He's going to go get our lunch.
0:06:01 > 0:06:04But Fido's a goldfish.
0:06:04 > 0:06:05Maybe he could go when it's raining.
0:06:11 > 0:06:14OK, I'll admit those dogs were pretty clever
0:06:14 > 0:06:17but I know an animal that is much smarter.
0:06:17 > 0:06:19- Really?- Mm. Just look at this.
0:06:20 > 0:06:24Corvids are a remarkable family of birds that includes ravens,
0:06:24 > 0:06:25crows and rooks.
0:06:27 > 0:06:30Wait, wait, wait, wait, wait. Birds? Birds aren't clever.
0:06:30 > 0:06:32Where'd you think the term bird-brain comes from?
0:06:32 > 0:06:35Birds may have small brains but it doesn't mean they aren't intelligent.
0:06:35 > 0:06:37Here, have a nut.
0:06:37 > 0:06:39Open it up, then.
0:06:39 > 0:06:42I can't. I haven't got anything to open it with.
0:06:42 > 0:06:44Tough nut to crack, eh? Tough nut.
0:06:44 > 0:06:46Well, that's not a problem for the corvids.
0:06:46 > 0:06:50Just look at these extraordinary crows in Japan.
0:06:50 > 0:06:54Nuts are one of the favourite nibbles but, just like you,
0:06:54 > 0:06:58they don't have a useful nut cracking tool to hand. Or wing.
0:06:58 > 0:07:02So instead, they've figured out an ingenious method of breaking
0:07:02 > 0:07:03and entering.
0:07:03 > 0:07:07They simply drop the nut on a nearby road
0:07:07 > 0:07:09and let the traffic do the work for them.
0:07:12 > 0:07:16I'd say that's crows one and Naomi nil.
0:07:16 > 0:07:17Yeah, but they won't be so smart
0:07:17 > 0:07:20when they get run over picking it up, will they?
0:07:20 > 0:07:22Actually, our clever crows have already thought of that.
0:07:24 > 0:07:28Because they're not dropping them on just any old section of road.
0:07:28 > 0:07:32No, these brainy birds are dropping the nuts onto a pedestrian crossing.
0:07:32 > 0:07:34- No way!- Yes way.
0:07:34 > 0:07:37When the green man lights up they simply hop in
0:07:37 > 0:07:39and take their well-earned snack.
0:07:39 > 0:07:40Incredible.
0:07:41 > 0:07:42Right, try this.
0:07:43 > 0:07:45- Oh.- Two nil.
0:07:45 > 0:07:47Here you go, here you go.
0:07:47 > 0:07:49Well that's not going to work, is it? It's too soft. Look.
0:07:49 > 0:07:51No, no, no, no.
0:07:51 > 0:07:54I want you to think what a crow could do with this.
0:07:54 > 0:07:56Well, they don't make sandwiches, do they?
0:07:56 > 0:07:58Better than that. Look and learn.
0:07:58 > 0:08:01This time we're off to Israel,
0:08:01 > 0:08:05where Oren Hassen was out feeding the hooded crows in his local park.
0:08:05 > 0:08:08Nothing special about that, but instead of eating the bread,
0:08:08 > 0:08:10just look at what this crow went and did.
0:08:13 > 0:08:15What?
0:08:16 > 0:08:20Yes, it would seem that this crow is using the bread as bait
0:08:20 > 0:08:21to catch food.
0:08:21 > 0:08:25In effect, it was fishing in exactly the same way that us humans do.
0:08:26 > 0:08:28How has figured that out?
0:08:28 > 0:08:33Well, many birds will dunk dry bread into water to soften it up a bit
0:08:33 > 0:08:34before they eat it.
0:08:38 > 0:08:41I'm not doing it for me.
0:08:41 > 0:08:43So it's possible a crow was dunking bread
0:08:43 > 0:08:46when it accidentally ended up with a fish in its mouth
0:08:46 > 0:08:50and that crow realised that the fish was a far better meal than bread.
0:08:51 > 0:08:54But this behaviour also raises the intriguing question
0:08:54 > 0:08:57of whether crows are capable of deferred gratification.
0:08:58 > 0:09:00Deferred gratification? What's that?
0:09:00 > 0:09:05Well, it's the ability to resist one reward in favour of a better reward.
0:09:05 > 0:09:08- For example, if I was to say to you...- Aw!
0:09:08 > 0:09:12Ah, ah, ah. If I was to say to you, leave this plate of marshmallows
0:09:12 > 0:09:14alone for just five minutes
0:09:14 > 0:09:17and then I'll give you two plates of marshmallows.
0:09:17 > 0:09:20Obviously, you're going to wait for the better reward, aren't you?
0:09:23 > 0:09:26For the crows, they have to resist the temptation of eating
0:09:26 > 0:09:29the bread for the bigger reward of the fish.
0:09:29 > 0:09:32It may not sound like much, but being able to think ahead like this
0:09:32 > 0:09:35is something very few animals are smart enough to do.
0:09:39 > 0:09:42Oh, you ate the marshmallows, didn't you?
0:09:44 > 0:09:47Birds catching fish might be pretty clever
0:09:47 > 0:09:50but what about a fish that can catch a bird?
0:09:50 > 0:09:54Ha-ha. Don't be daft. Fish can't fly.
0:09:57 > 0:09:59Flying fish.
0:10:00 > 0:10:04- Apart from those.- Not as smart as you think, are you, Tim?
0:10:06 > 0:10:08For our final bizarre happening we're off to the picturesque
0:10:08 > 0:10:11towns and river banks of southern Europe,
0:10:11 > 0:10:14where the waters hide a shocking secret.
0:10:15 > 0:10:18When pigeons come to drink and bathe at the river's edge,
0:10:18 > 0:10:20they really are dicing with death.
0:10:20 > 0:10:23A predator is watching their every move.
0:10:26 > 0:10:28What do you say to that, Tim?
0:10:28 > 0:10:30I'd say that was anomalistic
0:10:30 > 0:10:35and idiosyncratic behaviour from that ebullient piscine creature.
0:10:35 > 0:10:37Tim, are you just reading out long words from the dictionary
0:10:37 > 0:10:39to try and prove that you are smart?
0:10:39 > 0:10:43I repudiate any charge of circum...locution.
0:10:45 > 0:10:49So what kind of freakish fish would do something so unnatural?
0:10:49 > 0:10:52Closer inspection reveals a monstrous head
0:10:52 > 0:10:54with long protruding feelers.
0:10:54 > 0:10:57It's a colossal kind of catfish.
0:10:57 > 0:10:59Well, that explains it.
0:10:59 > 0:11:00What does?
0:11:00 > 0:11:02Catfish.
0:11:02 > 0:11:04Well, cats love eating birds, don't they?
0:11:04 > 0:11:07- You do know what a catfish is, don't you?- Yeah.
0:11:10 > 0:11:13But maybe there is someone watching the show that doesn't know what
0:11:13 > 0:11:16a catfish is, then perhaps someone should explain.
0:11:16 > 0:11:20How about freshwater fish expert Jeremy Wade.
0:11:20 > 0:11:24People tend to think of European catfish as being fairly
0:11:24 > 0:11:27sluggish creatures, snuffling around on the bottom,
0:11:27 > 0:11:31eating things like worms, crustaceans and muscles.
0:11:31 > 0:11:34Normally they live in quite muddy water.
0:11:34 > 0:11:38That's why they got those feelers stretched out in front of them.
0:11:38 > 0:11:42They have their eyes set towards the top of their head.
0:11:42 > 0:11:45They're very aware of what's going on above them.
0:11:45 > 0:11:47Oh, yeah, yeah, I already knew all of that.
0:11:47 > 0:11:51- Oh, right, shall I stop it, then? - No, don't stop it, no. It's rude.
0:11:51 > 0:11:53Once he's started, let him finish.
0:11:55 > 0:11:58They're very opportunistic so they will feed on small fish
0:11:58 > 0:12:00but also water birds.
0:12:00 > 0:12:03Things like ducks that are swimming or floating on the surface
0:12:03 > 0:12:05but I've not heard of them taking pigeons before.
0:12:05 > 0:12:10- Hang on a minute. He's an expert and even he's never heard of it?- I know.
0:12:10 > 0:12:14These crafty catfish have invented a whole new hunting technique.
0:12:17 > 0:12:20The catfish are approaching very stealthily.
0:12:20 > 0:12:23They're coming in very close to the water's edge.
0:12:23 > 0:12:25The prey is not going to come to the fish.
0:12:25 > 0:12:28The fish has to go to the prey, which in this case involves
0:12:28 > 0:12:32launching itself on land, making a lunge, a grab.
0:12:32 > 0:12:36Fido. Come on, Fido. Fido. Come on, jump. Up, up, up. Up, up, up, Fido.
0:12:36 > 0:12:37Jump.
0:12:37 > 0:12:42Of course, this is a dangerous tactic for a fish.
0:12:42 > 0:12:44If it were to end up marooned on dry land,
0:12:44 > 0:12:46the catfish would soon suffocate
0:12:46 > 0:12:49but, for these highly adaptable creatures, the prospect
0:12:49 > 0:12:53of a high-protein pigeon supper appears to be worth the risk.
0:12:56 > 0:12:59And by making themselves literally a fish out of water,
0:12:59 > 0:13:04I reckon they definitely deserve to be called clever critters.
0:13:05 > 0:13:09Aw, you know, all this talk of food, it's making me hungry.
0:13:09 > 0:13:12- Shall we stop now and get some lunch? - Yeah, OK.- All right. Good deal.
0:13:12 > 0:13:15Tell you what, you go get the fish
0:13:15 > 0:13:18- and I'll go and get the pigeon.- Oh.
0:13:18 > 0:13:20See you in a bit, yeah?
0:13:31 > 0:13:33# Wild and weird, wild and weird
0:13:33 > 0:13:35# Really really wild and really really weird
0:13:35 > 0:13:37# They're wild and weird, wild and weird
0:13:37 > 0:13:39# They're really really wild
0:13:39 > 0:13:41# They're really really wild and weird
0:13:44 > 0:13:47# Wild and weird. #