However well we think we know our planet, the natural world
still has the power to surprise us, to shock us, sometimes even to
scare us with its extraordinary events and bizarre behaviour.
Given modern technology, nature's weirdest phenomena are frequently
caught on camera wherever and whenever they occur, and this means
that we can bring you the strangest stories our world has to offer.
From animals that keel over at the first sign of trouble,
to bears grabbing a takeaway.
And a pigeon-snatching predator from the deep.
With the help of eye-witnesses, experts and scientists,
we're going to try and explain what on earth is going on.
The natural world can astound us with intriguing behaviour and
extraordinary designs, and in these weird events,
nature seems to have torn up the blueprint altogether
and come up with something truly bizarre.
Welcome to the world of nature's weirdest designs.
We're starting with the animals whose design appears to have
gone wrong right at the drawing board.
This is the stuff of myths and legends,
creatures so strange, they have to be seen to be believed.
From a lobster that looks half-baked, to a snake in two minds.
But first, we're off to the USA to meet some animals that may
look normal, yet something is making them act very strangely indeed.
Healthy looking goats that appear to drop down dead at the drop of a hat.
Oh, no, I've killed my wife's goat!
When the farmer Gene McNutt and his family moved to the peace
and quiet of Tennessee, they had no idea of the strange events
that would befall them.
We moved here to Tennessee in 1988.
My wife immediately wanted a new goat.
One of our neighbours was kind enough to bring her home
a six or eight week old goat and that goat became the pet of the house.
The McNutts adored their pet goat,
but then Gene had a very unnerving experience.
One day, the goat falls down and looks like he's gone stiff with
rigor mortis and I say, "Oh, no, I killed my wife's goat."
"What have I done? Has it had a heart attack?"
I'm standing there just in total amazement,
trying to figure out what am I going to do.
Had Gene suddenly developed the power to kill goats
just by looking at them?
Well, no.
Suddenly the goat wriggles a little bit,
gets up and walks off as if nothing had happened.
I decided to say nothing to my wife about it
since the goats appeared to be OK.
I asked the neighbour about the goat
because it was something that had never happened before,
and he says, "Oh," he says, "Those are just old nervous goats."
He says, "They're from around here."
Gene's experience wasn't a one-off.
These goats of the Deep South have a tendency to head south,
and then rise again unharmed.
So what's causing the goats of Tennessee to keel over,
only to be resurrected shortly afterwards?
Well, there could be a clue in what triggers their downfall.
Almost any noise that is unusual will cause the goat to stiffen
or fall over and it'll stay in a fallen position for 30,
45 seconds and sometimes even up to a couple of minutes.
Shirley's down.
Sometimes just a quick movement by a person will cause the goat
to fall over.
Almost every morning when I feed the goats,
at least one of them will fall out
and all I'm doing is pouring feed out of the bucket.
So, stress or excitement seems to be a factor in falling over.
When threatened or surprised,
many animals have a fight or flight response.
Their muscles suddenly tense up, as they prepare to run away or attack.
Freezing for a moment is part of a vital survival strategy
for some wild animals, but it seems that these goats in Tennessee
have a glitch in their system.
Instead of freezing for just a split second, they completely seize up.
This unusual reaction is unique to a particular breed called
fainting goats, although they don't actually lose consciousness.
So what makes this happen?
Well, it's all down to a genetic disorder called myotonia congenita,
and it affects how their muscles work.
The muscle fibres contract as normal, but then they don't relax
afterwards as they should, so these goats become temporarily paralysed.
It's a condition that they learn to live with.
When they're young, a lot of things will make them faint,
but as they get older, even though they'll stiffen up,
most of the time they'll find something to lean on
or they'll get their balance because they know that if they're off balance
then they'll indeed fall over.
These domesticated goats don't seem to suffer any ill effects,
but clearly this could be a problem in the wild.
Wild goats are renowned for their agility.
If they fell over whenever they were startled or a predator approached,
this genetic flaw would prove fatal.
So why did this weird phenomenon turn up in the goats of Tennessee?
There's a local legend to explain their genetic quirk.
About 1885, a man came to a little community called
Caney Springs here in Marshall County, Tennessee.
With him he brought three or four little goats.
The unique thing about these three little goats,
is that when they're startled, they fall over.
All fainting goats alive today are descended from that one small
original flock and it appears that inbreeding has led to some
genetical mis-wiring and their natural defence system
has gone awry.
Now, of course, in the wild, this behaviour would be treacherous.
It doesn't seem to be too much of a problem in a domestic herd,
but then having said that, to us, it seems very strange indeed.
From fainting goats that foxed many farmers,
we move on to sea creatures which are freaking out fishermen,
with a design flaw that's clear for all to see.
We head to the Atlantic Coast of North America, where a fisherman
landed a lobster that will have you adjusting your TV sets.
I just jumped aboard the vessel.
Just caught this blue Maine lobster.
An astonishing bright blue lobster.
A vivid contrast to its normally-coloured companion,
and if one electric blue lobster wasn't shocking enough,
another turned up, but it didn't stop there.
Ah, we got ourselves another crazy lobster down here.
Pretty funky, pretty cool.
Another was brilliant orange, the colour that lobsters go
when they're cooked, and yet this one was very much alive.
And just when they thought they'd seen it all, up from the depths came
this, an impossible looking lobster with a jaw dropping colour split.
So, what on earth can explain these colourful crustaceans?
To find out, we need to delve deeper and take a closer look
at the colouring of normal-looking lobsters.
This is what an adult lobster looks like in the wild
and they get their colour as they grow, from the food that they eat.
They feed on a diet of crustaceans, shellfish and zooplankton
and many of these organisms have a red pigment inside them
called astaxanthin.
It's the same pigment that makes salmon pink.
And it even gives flamingos their trademark colour.
So why don't lobsters turn pink if they're also eating astaxanthin?
When the red pigment is absorbed into the lobster's body,
it's laid down in its muscles and into a membrane that
lies beneath the shell.
But over a period of time, it migrates into the shell
where it's transformed by a protein into a blue pigment.
A little later, it migrates again right up to the
surface of the shell where it meets another protein which
transforms it for a second time into a yellow pigment like this.
Now, when they are all overlaid, we get to see what we see
when we look at the lobster, this dirty brown-y green colour.
This layering of colour provides good
camouflage down on the sea bed where lobsters spend most of their lives.
It keeps the young safely hidden and allows adults to stalk their prey.
Understanding the mix of colour layers in normal lobsters
means we can work out how this design can go wrong.
What happens if we remove one of those pigment layers,
say the blue one?
Well, then we're left with this, an orange-looking lobster.
But why would a lobster be missing a blue layer?
Crustacean expert Dr Grant Stentaford
knows the answer.
The orange lobsters which are abnormal, are actually missing
a very important protein, a blue protein which is
normally in the shell, and that's not produced because of a genetic defect.
So, it's a genetic design flaw that makes some lobsters bright orange.
So could the same be true for blue lobsters?
Well, people may think it's
because the lobster is missing the red or the yellow pigment
from the shell, but actually, it's more likely to be due to an
over-expression of the blue protein, or possibly the fact that the lobster
is not absorbing those red pigments from the diet that it's eating.
So the strange looking lobsters of America's East Coast
are in fact extremely rare colour mutants.
But what about that extraordinary two-tone lobster?
What's going on there?
Just before Halloween in 2012, in the waters
off of Salem, Massachusetts, this creepy crustacean was hauled in.
It's mutant orange on one half of its body,
but normal coloured on the other.
The men who caught it, Dana and Ryan Duhaime,
had never seen anything like it before.
Right away when it came on deck I said, "What is this?"
I couldn't believe we had a lobster that was orange on one side
and black on the other and straight, straight, right down the middle.
We couldn't wait to take it in to show these guys on the dock,
you know, what do you think of this?
Unlike us, each side of a lobster's body
develops completely independently.
To explain this, we have to go right back to the drawing board.
Let's look at the beginning of a lobster's life.
Once the sperm has fertilised the egg,
it grows and splits into two cells.
And this is an absolutely critical time for the lobster,
because this initial spit will define how each side of its body
develops and remains for the rest of its life.
Now very occasionally, as it makes this initial split,
there's a genetic mutation, say in the form of the genes
that code for colour.
So, if there's an abnormality on one side, as each of these cells
is replicated and the lobster grows, then that genetic
abnormality will be replicated too.
What we end up with is this,
a lobster split directly in two with a weird colour mutation on one
side and it's all down to that initial cell split.
And that explains what happened with our Halloween lobster.
But, incredibly, it's not unique.
This one from Newfoundland has an even stranger design flaw
which can also be traced back to the original cell split.
As well as turning black and blue,
it has a mutation in its sex chromosomes.
And this means that we end up with a lobster which has female sex
organs on one half of its body and male sex organs on the other half.
Almost all of the two-tone lobsters ever recorded have been
different sexes on each side.
This rare half-and-half layout is found in other species,
again where each side of the body develops independently
and where the males and the female look different.
We'll see it in butterflies and other insects.
In those cases, again, the sexes are different on both
sides of the animal, and we often see wing differences
so they can be different shapes and even different colours.
Two-tone lobsters have been surprising fishermen for a
while now, but scientists have only recently unravelled
the colourful tales that explain their appearance.
And with most lobster populations off the Atlantic Coast increasing,
we'll no doubt see more of these weird and wonderful colour mutants.
So, colourful crustacean conundrum solved.
Now to meet a true creature of legend, face to face.
On September 17, 2013, snake breeder Ross Gregersen
was checking the Mojave python eggs he was incubating.
So here's our last clutch of the year, here's the first Mojave.
Ross made a shocking discovery. Here's our second one.
When I first saw him, I thought he's either dead
or he's kinked or something cos his neck's pretty goofy looking.
I poked him and he shifted and I saw this
and realised that I have a two headed Mojave.
Amazingly, both heads of this snake are alive.
And it's not a one-off.
For snake enthusiasts, two-headed animals are highly prized,
especially when the split is perfect and symmetrical like this one.
Ben Siegel owns a reptile shop
and his striking looking snake has become world famous.
This is Medusa, she's our two-headed albino Honduran milk snake.
She was born a couple of years ago and she's the mascot at our store.
I've been keeping snakes since I was six, so about 34 years,
and I've never quite seen one like her before.
We love her, she's really special to us.
She's perfect other than... she's more than perfect.
So how do snakes end up with two heads?
And what kind of double life do they have to lead?
A snake with two heads is the result of incomplete twinning.
It happens when the snake embryo is developing,
either in the egg or the womb.
The same thing can happen with human embryos
if they split into identical twins.
A glitch in the separation process means it grinds to a halt.
In this case the result is conjoined snake twins each with a head.
But as this X-ray shows, the head joins a single spine
and they share the rest of their body.
Not surprisingly, such an unusual design
sets the snake several challenges.
Gordon Burghardt at the University of Tennessee
has kept and studied two-headed snakes.
We had one animal,
that black rat snake that lived for about 20 years and we recorded
lots of its behaviour,
but in the wild, they have, I think, great difficulty.
For a start, how does a two-headed snake decide which way to go?
Well, let's look at how normal snakes move
through the world in their natural environment.
With no limbs, they propel themselves along
with a slithering motion.
Snakes can only travel quickly for short bursts,
but if a predator appears, they need to make a split second decision
to find cover.
This is a problem for a two-headed snake
because each head has an independently thinking brain,
so it's always in two minds about which way to go.
But getting around isn't their only problem.
What happens when they want to eat?
When we feed her, we take and put her in an empty, clean, open tub,
and one of our employees actually takes two food items at the same time
and tries to lure one head to one side and one head to the other side,
trying to introduce the food at exactly the same time,
so they both grab it.
Often at times, we'll actually, when one head swallows it down quickly,
we'll give it another food item so that ideally you want them to both
finish at the same time.
Then after we feed her, we have to take her
and wash her heads off with water and soap,
so that she doesn't smell like her food because then both heads
will try to attack each other just from the smell of the food
on the head.
This may sound bizarre, but smell is a critical sense for snakes.
Although some have good eyesight when it comes to
finding their prey, most snakes rely on smell more than vision.
Their tongues play a vital part in smelling.
They waft odour molecules into a structure called
the Jacobson's organ, which detects the smell.
When it comes to the smell of food,
they follow their tongues to the meal.
For a two-headed snake, a meal could be confused with
the smell of leftovers on its other half.
Evidence surely that two heads aren't always better than one.
Fortunately, Medusa is well cared for and this helps reduce
the chance of a mishap.
But in some cases, this competition for food may be more
deep-seated than we imagine,
as Gordon discovered with one of his two-headed snakes.
From all the records we had heard about,
the two heads, the animals have necks and they swallow the prey
and they go to the common stomach.
So this was what we had thought was going on,
until we did some x-rays of the animal actually feeding
and what we found is that the animal actually had two stomachs.
So their motivational systems were somewhat independent.
These were individual animals in a sense that they did co-operate
and learn to do maybe some things a little bit better together,
but, basically, they were two minds in the same body.
So, two-headed snakes are rare enough in captivity.
Just imagine seeing one in the wild.
Well, believe it or not, that's what happened fairly recently
when a group of hikers were out in the Yorkshire hills.
They spotted one of these, an adder, Britain's only venomous
species of snake, and snapped a few photos before it slithered away.
It was only when they looked at them more closely afterwards,
they recognised that the snake actually had two heads.
An amazing rarity, a UK first and experts think that the animal
is already a few months, perhaps even a year old,
so it's doing a good job of surviving in the wild.
I'm absolutely enthralled by the thought that this snake
might still be out there somewhere.
All of these stories make us stop
and think twice about what happens when nature's blueprints go wrong.
Whether it's goats overcome by the slightest excitement,
mutant lobsters equally in touch with their masculine
and feminine sides, or snakes who are in two minds about life.
These wonderful, exceptional animals remind us
that, incredibly, most of the time, nature gets it completely right.
Next, we meet animals that are pushing the limits of what
they're designed to do, deploying shocking tactics to secure a meal.
There's a fish taking a leap into the unknown,
and a bird using brain power to expand its menu.
But first, we're heading to the State of Colorado to investigate
an alarming animal crime wave.
It's the early hours of July 31st, 2013 and a shifty individual
is targeting a one-tonne waste bin at the back of this restaurant.
This isn't so much dumpster diving as dumpster driving.
The next night, he comes back and steals another dumpster.
This black bear is a repeat offender.
On another night in July, a different shady character is caught
breaking into this chocolate shop in the town of Estes Park.
This is a high calorie heist.
So, what's driving these bears to commit a summer crime wave
in Colorado?
Well, when it comes to diet,
black bears eat pretty much what we eat.
Fruit, vegetables, meat and fish,
so our food makes a good meal for them too.
This restaurant robbery took place in Colorado Springs.
It's nestled at the base of the Rocky Mountains,
an area with a huge population of black bears.
But this is the scene of the crime, a full two miles into the city.
The bear went for the bins around the back, so what lured him
so far into town?
Well, he was almost certainly led by his nose.
Bears have a sense of smell that's even more powerful than bloodhounds.
Our bear probably smelled the city leftovers from miles away.
In fact, he might have visited several
restaurants before being caught on camera at Edelweiss.
So now we know how the bear targeted the restaurant.
But how did he manage to move the heavy dumpster?
Wildlife cameraman Jeff Turner,
who's filmed bears for decades, has some ideas.
The bear's able to do what he does with that dumpster
for three basic reasons.
The first reason is the way that his feet are built.
His feet are built much like a human's or a great ape.
He can actually stand on the flat of his feet which allows him to
stand up quite comfortably in order to reach the top of the dumpster.
And then he's got very dexterous paws like his claws
and individual use of those digits and his paws allow him
to actually grip things.
The edge of that dumpster, he can get a good grip on it.
And then the third element that allows him
to move it is his strength. They're very, very strong animals,
very, very powerful, so it's nothing for him
to move something that heavy once he's in that position.
Bears have this dexterity and strength
because of the way they feed in the wild.
Perhaps, surprisingly, a lot of their calories come from insects,
which they find by moving boulders and ripping open rotting logs.
All in all, bears are actually well designed for dumpster-driving.
But where was the bear going with its haul?
Well, it turns out it was wheeling it around the corner
into a car park, to feast on the contents.
So, why go for a takeaway each night when it could have dined
al fresco at the back of the restaurant?
Bears, it seems, prefer to dine alone.
They don't like to be caught out unawares either by other
hungry bears or in this case, by humans.
All the activity and the bright lights at the back
of the restaurant are enough to put a bear off his food,
so he takes his meal-on-wheels to a quieter spot in the car park.
But why is there a spike in bear crimes in late summer,
when both of these events occur?
It's all because bears have to hibernate each winter.
Before they can do this, they must pile on the pounds
so they have enough fat to live off during the cold months.
From the end of July onwards, they all start binge eating.
That's what triggers the late summer crime wave.
It certainly provides the motive for that raid on the chocolate shop.
Last week, a young black bear broke into
Rocky Mountain Chocolate Factory in Estes Park and had a heyday stuffing
himself silly full of chocolate treats from the popular candy shop.
Seven times the bear came in, took a pile of chocolate
and went outside to eat it, getting a massive sugar hit.
And there's a theory for why the bears in Colorado,
a landlocked state,
might be more prone to pilfering than bears living near the ocean.
In this sort of an environment in the interior of the continent,
they don't necessarily have access to salmon like they would on the
coast, so their main source of food at this time of year
would be berries.
And berry crops are less nutritious than fish,
and notoriously unpredictable.
One year they might be plentiful, the next, they could be thin
on the ground, driving hungry bears into town to stock up before winter.
And just one last thing that explains why our bear is
so confidently calling for a takeout.
Just look at the way he approaches the dumpster that first night.
He already knows that this is a giant lunchbox to go.
And he's clearly enjoyed the contents of these before
and that's because he probably learned his larceny many years ago.
Bear cubs learn where to find food from their mothers.
Research suggests that the cubs of females that forage in urban
areas grow up to do the same as their mothers.
And there's increasing evidence that these bears will
head into town even when there's plenty of natural food on offer.
The result is a new, streetwise, bear-gang on the block.
Not only do they have a taste for fast food,
they've got the brawn, the brains
and the light-fingeredness to get at it all.
Our bear's midnight feast came to an abrupt end
when the owners of the Edelweiss restaurant bear-proofed their
dumpster and cut off his supply of schnitzel and black forest gateaux.
But then biologists quite often have to relocate thieving bears
into the wilderness.
Trouble is, this doesn't always work.
You see, these animals have extraordinary navigational ability.
Even the cubs can build quite complex mental maps far
better than our own. It's like they've got their own sat-nav.
So if you take them 60, 70 miles away,
within a day or two, they can be right back in town.
But the quest for food takes our next animal
into even more uncharted territory.
It's life and death on the waterways of Southern Europe.
This is Albi, a beautiful town in the South of France.
It's steeped in history, and famous for the picturesque bridges
which cross over the River Tarn.
But these waters hide a shocking secret.
When pigeons come to drink and bathe on the river bank,
they are dicing with death.
A predator is watching their every move.
And French scientists are capturing astonishing events,
never seen before.
Hundreds of miles away in the Spanish city of Zaragoza,
people are stopping in their tracks to watch the same disturbing scenes.
THEY SPEAK ITALIAN
One by one, the unsuspecting birds are being plucked from the bank.
So what is preying on these pigeons and dragging them to a watery grave?
Huge fish.
But surely they're risking their own lives to leap onto land?
So what kind of freakish fish would do something so unnatural?
Closer inspection reveals a monstrous head with long
protruding feelers.
It's a colossal kind of catfish and this species
isn't meant to be here at all.
In the 1980s, fishing enthusiasts brought these catfish
from colder climes, introducing them to several parts of Southern Europe.
Since then, their numbers have grown steadily, but this is the first
time they've ever been seen lunging onto land to catch birds.
To explain why they're making such a splash in the south of France,
we need to understand how they normally find food, something
that freshwater fish expert, Jeremy Wade, knows a lot about.
People tend to think of European catfish as being fairly
sluggish creatures, snuffling around on the bottom,
eating things like worms, crustaceans and mussels.
Normally they live in quite muddy water,
that's why they've got those feelers stretched out in front of them.
They have their eyes set towards the top of their head,
they're very aware of what's going on above them.
They're very opportunistic so they'll feed on small fish
but also water birds, things like ducks that are swimming or
floating on the surface, but I've not heard of them taking pigeons before.
Catfish are voracious predators.
To catch their prey, they sneak up behind it.
At the last moment, the catfish opens its mouth creating a huge
inrush of water that literally sucks the creature in alive.
But this won't work with pigeons stood on the bank.
So how have the catfish managed to modify their technique?
The catfish are approaching very stealthily.
They're coming in very close to the water's edge and they appear to
have their feelers stretched out in front of them and what they're doing
with those is feeling vibration.
They seem to be targeting the birds that are moving,
rather than the ones that are standing still.
The prey is not going to come to the fish,
the fish has to go to the prey, which in this case involves
launching itself on land, making a lunge, a grab.
These catfish are doing something rarely seen
anywhere in the world.
They are propelling themselves into elite company,
alongside one of nature's most formidable hunters.
Killer whales off the Patagonian coast also beach themselves
to catch young sea lions.
This spectacular behaviour is a risky tactic,
but at least if they get stuck on the beach,
these mammals are able to breathe air and the reward
of a high protein meal is well worth the risk.
The European catfish are taking the same gamble by hunting pigeons
but the risks are even greater.
They can't breathe air and they could end up beached.
It's the chance of catching the pigeon that makes it all worthwhile.
But French researchers have found that not all
the catfish are making the leap onto land.
It's just a select group of medium sized fish,
ones which are about a metre long.
So why do only these fish hunt the pigeons?
You've got a very gently sloping riverbed there.
The medium sized fish are able to get within range of the pigeons
without the pigeons realising they're there.
A bigger fish tries that, actually half its head is going to be
out of the water.
Before it gets close, that pigeon's going to
realise something's up and get out of the way.
So these medium sized fish are doing it because they can.
But hunger may also be driving them to find food on land.
Maybe the bigger fish are running the river, they are the ones that
have first choice of the normal foodstuffs, but you have this
interesting situation where the medium sized fish have access
to something else that the bigger fish don't seem to be able to reach.
28% of the lunges result in a meal.
That's a good hit rate for any predator.
Fuelled by a high protein diet, these medium sized catfish look set
to join the big boys pretty quickly.
And the irony is, as soon as they grow, pigeon will be off the menu.
But all of this begs the question.
Given the benefits of this feathered food supply,
why haven't catfish done this before, in more locations?
It's to do with where they are.
An introduced species, these cold blooded killers are now
living in warmer climes for the first time.
What I think is probably a factor here is water temperature.
The water in this part of France is significantly warmer
than in their historical home range and what this is going to do
is raise their metabolic rate.
It's going to make them more active, more predatory in their behaviour,
they eat more, they grow bigger, faster.
So, there's a good chance that pigeons will be a la carte
in more places across Southern Europe as catfish numbers increase.
To take advantage of their new home, these fish have shown
remarkable ingenuity, completely changing the way they behave.
They may look primitive,
but catfish are really amazingly adaptable animals.
In the wild, they live for decades and they grow to a colossal size.
The European record was a fish caught in Italy.
It measured nearly 3m in length and weighed in at a staggering 144kg.
It's no wonder that there are stories out there
about these animals feeding on water birds the size of swans
and even swallowing dogs that were swimming in fresh water.
They truly are, if a little unexpectedly, monsters of the deep.
Big fish have crossed a line in Europe to hunt birds,
but in our next story in Israel, the tables are dramatically turned.
Not far from Tel Aviv, in a city park,
the local hooded crows have been doing something unheard of.
Like many urban birds, they'll happily take a hand-out,
but these crows aren't settling for crumbs.
Local resident Oren Hasson
enjoys watching their everyday antics in the park.
Then, one day, Oren filmed a crow taking a piece of bread.
It dropped it into the water and then...
Yes, yes, that crow just caught a live fish.
Crows have never been seen catching fish before and what's really
extraordinary, is that they appear to be using bait to lure them in.
So how have these crows learned to fish for a living?
First, we need to know more about the bird family that they belong to.
The corvids.
Many of the corvids have a reputation for their curiosity
and their problem-solving abilities, and I hope to demonstrate that now
with this raven, because underneath here I've got a test for him.
Now go on, jump down.
Immediately, he's started pulling out the string
because he knows that on the end of that is a ball
with some food in it and now he's got the reward.
Pretty smart, eh?
And remarkably, there are other cases of corvids in the wild using
ingenious techniques to find food.
These rooks have made a pit stop at a motorway service
station in the UK.
They've worked out how to get food from the very
bottom of the litter bins without risking getting inside.
They use the bin liner as a tool, pulling it up to haul the food out.
So, birds like crows can be pretty clever.
But how have the crows in Israel developed their angling abilities?
Many birds dunk dry bread into water to moisten it before they eat it.
Perhaps one accidentally ended up with a fish in its mouth.
That crow might have realised that the fish was a far better meal
and got hooked on fishing.
But then several other crows were deliberately seen using
bread as bait.
Cambridge Crow expert, Nicky Clayton,
thinks there's another intriguing possibility.
Was the bird able to figure out that bread would make a good tool
to use to lure the fish?
Did it have a plan, a series of steps in its head that it's worked out
before it's actually executed any of the behaviours?
So could these crows be thinking through a clear strategy?
What's intriguing about the video is whether the hooded crows
are actually capable of delayed gratification.
That is do they understand that by using a piece of bread
as a tool to lure the fish
they can actually get a much better reward
later, the fish, rather than just eating the piece of bread right now.
Delayed gratification for an animal like this crow is no mean
achievement, particularly as it's not something that comes easily
to humans.
Child psychologists have known for a long time that
if you offer children under five one marshmallow now,
or two marshmallows later and then you leave one on a plate for 15 min
by the end of that period it's almost invariably gone.
-And who can blame them!
When crows resist temptation like this,
they also reveal another remarkable ability.
They've got an awareness of time, and that's something,
planning ahead, remembering the past that was thought
until quite recently to be unique to human beings.
So, crows can make and learn to use tools to help them find food.
And they're capable of forward planning and delayed gratification.
So how is all of this possible for a bird brain?
It turns out that crows are a cut above most of their feathered
friends when it comes to the old grey matter.
When we look at the structure of crow brains,
they have areas which are enlarged compared to other birds
and these same areas are the ones that in our brains relate to
memory, planning ahead and delayed gratification.
These amazing new discoveries are leading scientists to make
striking comparisons between crows and great apes.
Relative to their body size,
crows and chimpanzees have equivalent sized brains.
They both use tools and scientific tests are starting to show
that by some criteria, crows are as intelligent as chimpanzees.
Somehow, these very different animals have both developed similar
kinds of brainpower.
It's a mind-blowing thought.
Who'd have guessed that feeding bread to birds in the park
could lead to such startling revelations?
These stories show the extraordinary mental
and physical lengths that animals will go to get a meal.
Whether it's a bear pushing the boundaries,
an astonishing fish out of water,
or a bird brained genius.
These animal innovators have stretched the very
limits of what their brains and bodies are designed to do.
Next, to the design of some of nature's weirdest defences,
improbable strategies for personal protection or
the survival of a whole species.
From birds acting like lame ducks, to shrinking reptiles.
But we start in the USA with a defence strategy that appears
to have backfired terminally.
From time to time, Americans stumble upon apparently dead bodies.
Uncle, pick it up! I ain't touching that thing. Must be poisoned.
I don't want to touch stuff like that. Is it going to bite?
Finding what looks like the corpse of a baby rat can be
an unsettling experience.
Watching one lose the will to live in front of your eyes
is even weirder.
Has it died of fright?
Well, no, because these are North American mammals called
Virginia possums, often known as possums for short.
See this thing? It looks dead, doesn't he?
But he isn't. He's just playing possum.
So what is this possum playing at?
The American expression "playing possum" refers to someone
pretending to be dead, and it was inspired by this behaviour.
This bizarre phenomenon is known as thanatosis.
The possum goes stiff, then opens its mouth
and drools with its tongue hanging out.
Its eyes stay open but its breathing becomes slow and shallow.
Despite appearances, its heart continues to beat at a normal rate.
The possum isn't really shutting down, it's just faking it.
At first glance, this is a fatally flawed defence strategy.
The possum is in mortal danger. Oh, my gosh! So why doesn't it run away?
Well, needless to say, possums are not as daft as they look.
Their natural predators include horned owls, coyotes,
bobcats, foxes and racoons.
But with a top speed of about 7mph, running isn't an option,
so the possum doesn't stand a chance against most of these animals.
Yet pretending to be dead when confronted with something
that wants to eat you still seems like a strange response.
But seeing a coyote hunt a possum suggests how faking death
might be the best way of avoiding real death.
The coyote thinks the possum is dead already
so it doesn't bother to kill it.
It switches from full-on attack mode to a more gentle,
meal-handling behaviour.
But the possum is still on the menu so surely real death is inevitable.
Predators don't always get stuck into a meal straight away.
Some species, like owls and foxes, actually hide food for later.
Anyone keeping chickens will know about this scenario.
The fox takes one carcass away from the coup
and hides it in a food cache, returning for another body.
Substitute a death-feigning possum for a chicken
and it would find itself being abducted to the cache site
and then left.
Left for dead, at which point the possum wouldn't make its escape.
The case of the coyote reveals the second reason that
playing dead works.
Predators often kill opportunistically
and if they aren't actually ravenous,
they might lose interest in the prey when it appears lifeless.
That means the possum still has a chance.
Whilst the coyote's back is turned, it can slip away,
slightly worse for the experience, but at least it's alive.
So, faking your own death is a risky but effective strategy.
But possums aren't the only animals to evolve what might
seem like counter-intuitive anti-predator strategies.
It happens here in the UK too. These are little ringed plovers.
They lay their eggs on a patch of shingle.
The eggs are speckled for camouflage, but on the ground,
they're still vulnerable to predators like foxes and jackdaws.
This jackdaw knows the eggs are there somewhere,
but the parent birds have left the nest and are flapping
about right under the jackdaw's nose, but this is all a ruse.
Look at the bird in the foreground,
pretending to have a broken wing, trying to look injured
and vulnerable and show that they would be an easy meal.
This is a distraction designed to draw the predator
away from their eggs.
In this case it didn't work. But the strategy is often successful.
As soon as the threat has passed, they drop the act
and return to business as usual.
Birds are likely to perform these distraction displays
at the most critical point in their breeding cycle,
notably when the eggs are just about to hatch.
If they fail there, then they've wasted an entire breeding season.
Oh, and one last note on these bizarre displays.
On land, it's likely that you'll see birds performing them.
Because they're very agile, they can fly away if there's any trouble.
Less mobile animals, well, if they practise this sort of deceit
and get it wrong, it could be fatal.
Some of nature's best defences involve going unnoticed.
We're off to Madagascar to discover the ultimate in downsizing.
A huge island off the coast of Africa, Madagascar is a strange
looking land, and home to an impressive array of animal oddities.
Some of the weirdest are the chameleons.
Here, there are more species of these larger than life
lizards than anywhere else on earth.
These eye-catching characters are shaped in the classic
chameleon design.
They're big, bold and famous for their telescoping tongues.
And, of course, for their legendary ability to change colour.
They use this to communicate with each other
and to blend into the background to avoid predators.
But in 2012, scientists were exploring the furthest
fringes of Madagascar when they discovered this.
A tiny chameleon, and the world's smallest reptile.
It was so astonishing that it made headline news.
It measures just 29mm, and this is a fully grown adult.
This strange new species, named Brookesia micra,
is a fraction of the size of its flashy cousins.
So why would a lizard adopt this extreme miniaturised design?
Frank Glaw, of the Zoological State Collection in Munich,
made this diminutive discovery and he was instantly intrigued.
It's always a great exciting feeling if you discover new species,
especially if you can immediately recognise it as new.
In this case, it was so small, it was immediately clear
that it is different from all the other dwarf Brookesias
and so it was very exciting to have this small animal in our hands.
Brookesia micra belongs to a family of highly specialised
dwarf chameleons.
These little lizards have found a niche down in the leaf
litter of Madagascar's forests.
Scientists think there may be less predators here, and certainly
their dull brown colouring means they're very well camouflaged.
There are more of these dwarf chameleon species in Madagascar
than anywhere else in the world.
But why is Madagascar such a hot spot for these
incredibly tiny chameleons?
What is it about this place that might favour a tiny design?
Well, it's possible that island life tends to promote the little guy,
something known as insular dwarfism.
It suggests that when a normal sized species is
trapped on an island or on an isolated patch of land,
over time, it actually evolves into a smaller creature.
This shrinking process might happen if food was in short supply.
Only the smaller individuals will survive,
because they can get by on less.
When they reproduce, they'll have smaller offspring,
and so on and so on.
Down-sizing, then, can be a long term survival plan.
OK, so that might explain how the other dwarf
chameleons on Madagascar's mainland came about,
but Brookesia micra was found on a little island
off of Madagascar's north coast.
Here, resources are even more limited.
We have the large island of Madagascar that favoured
evolution of tiny Brookesias, and then
we have tiny offshore islands and so we could expect that natural
selection will favour even more tiny chameleons than on the mainland.
So, Brookesia micra's diminutive design may be
the result of a double dose of down-sizing.
This remarkable little animal has yet to reveal all of its secrets,
and, incredibly, scientists think there's a chance that these
chameleons may get even smaller in the future.
Shrinking yourself as a defence strategy is certainly pretty weird,
but then again it's working for the miniature chameleons of Madagascar.
The question is though, just how much smaller could they get?
Well, it appears that there might be a limit to miniaturisation
governed by the complexity of one organ.
It's not the heart, it's not the lungs, it's not the liver,
it is in fact, the eye.
As these stories show us, many of nature's defence plans
are stranger than we could possibly imagine.
Whether it's a possum faking its own death,
birds deploying distraction techniques
or lizards shrinking into the background,
they're all strange and curious designs
showing nature at its weirdest.
So there you have it.
We have witnessed some shocking events,
uncovered some fascinating new science
and also seen the weird and the wonderful.
And with its bizarre animal behaviour
and strange natural phenomena,
there's no doubt at all that the natural world still has
the power to leave us both baffled and amazed.
And with so much more to discover,
it also leaves us with one last question.
What on earth next?