Life in Cold Blood (2008) s01e03 Episode Script
Dragons of the Dry
ATTENBOROUGH: About 340 million years ago a brand new family of animals was evolving in the primeval swamps.
They were to go one step further than the amphibians who had emerged onto dry land before them.
For they would eventually completely cut their ties with water.
They were the ancestors of todays lizards.
They evolved scaly impermeable skins and moved up into the forests.
They diversified into a multitude of different shapes and sizes.
They developed signalling systems to communicate with one another.
And they squabbled as animals do over mates and territory.
For food they hunted insects that were already well established on the land in great numbers.
And here without returning to water they produced their families.
They powered their bodies not only with food but with the heat that they drew directly from the sun.
As they diversified so they spread into the harshest of the lands habitats.
The baking waterless deserts which eventually they would come to dominate.
The bigger ones are truly powerful and fearless.
Rearing up theyre well able to defend themselves with their front legs if theyre threatened.
This is a very intelligent animal.
It is observing me just as I am observing it.
Its a monitor lizard and its king of this country the Australian outback.
It is frightened of pretty well nothing obviously including me and it will chase and hunt and eat pretty well anything.
There are several thousand lizards round the world and they are truly the dragons of the dry.
Their eggs on land had to be encased in shells to prevent them from drying out.
And what better place to lay them could a mother lizard find than a termites nest? Worker termites labour unceasingly to keep the temperature and humidity virtually constant for their own benefit.
But that also makes their mound a near-perfect incubator for eggs of others.
After 1 0 months theyre beginning to hatch.
These are baby lace monitors.
But they face a major problem.
A termite nests walls can be a foot thick and extremely hard too hard for the young monitors to break through.
They are imprisoned with no food.
For a week after hatching theyre sustained by the last of the yolk that remains in their stomachs.
But when that comes to an end they could starve.
An adult lace monitor is nearby.
It may or may not be the babies mother.
If not then it could be a threat for monitors are hunters and will eat most small animals including baby lizards.
Shes nearing the termite nest within which the young are trapped.
She could be looking for a place to lay her eggs.
Alternatively she might be searching for food such as little lizards.
The babies are released unharmed.
Perhaps she is indeed the babies mother and not only remembered exactly where she laid her eggs a year ago but knew that her babies would need her help to escape from the incubator.
The young however are free.
But the outside world is a dangerous place.
They head for safety up into the trees.
In the branches there are other kinds of lizards.
jacky dragons.
Each has its own territory and warns others to keep out.
A wave of the front leg and a bob of the head is a jacky dragons way of claiming territory.
Here the action is slowed down.
In reality the leg flick is so swift its hard for us to see but its very plain to another jacky dragon.
But sometimes signals are not enough.
Physical violence is needed.
Hes won.
The vanquished acknowledges his defeat with a different signal a slow leg wave with no head bob.
The winner returns to his territory in the branches and announces his victory which his neighbour acknowledges.
So now both can live alongside one another in peace.
Once jacky dragons stop signalling it is quite hard to spot them up in the branches.
American anoles are so well camouflaged theyre virtually invisible.
Theres one on this tree right in front of me.
But he too needs to draw attention to himself to warn off rivals and then to disappear from predators.
This mirror may persuade him to reveal his solution to the problem.
Now then what do you think of that? Whos that? Yes its a rival.
A tail wag.
Yes.
(LAUGHING) Youre not going to get rid of me that way.
Show us your signals.
Well press-ups certainly is a keep-away challenge.
And there.
Thats it.
The full works.
(LAUGHING) Ah.
Lovely.
Once more.
Thank you.
And again.
(LAUGHING) Come on.
He obviously thinks that his position is being contested and he is displaying to show that he is as good as anybody else.
So I guess Ill leave him in peace.
An anoles throat flap appears for only a second or so and then vanishes.
And its owner after sending his message returns to camouflaged obscurity.
Another family of lizards living in the treetops has an even more varied repertoire of signals.
They use not only gestures but body colours.
Theyre chameleons.
Their stronghold is the island of Madagascar.
And here there are over 60 different species of them almost more than in all the rest of the world put together.
This is a panther chameleon.
And its marvellously adapted for life among the branches.
Its toes are divided into two bundles three and two.
And that means that it can use them just like forceps.
Their grasping feet supplemented by their gripping tail enable them to become remarkable slow-motion acrobats.
I suppose chameleons are best known for their ability to change colour and that does help in camouflage.
But actually they also use colour change as a way of communication and expressing their emotions.
When a male panther chameleon spots a rival he expresses his fury in glorious technicolor.
Malawi in central Africa may not have as many species of chameleon as Madagascar but it has one of the largest Mellers chameleon that can be 60 centimetres nearly two feet from nose to tail.
Rival males when they do battle deploy a range of threats that is truly formidable.
If signals dont deter then they start to joust.
Its not only males that fight.
There are also battles between the sexes.
This is the South African dwarf chameleon.
A male in full courtship costume.
This somewhat less colourful is a female.
She is not welcoming his advances.
As her mood darkens so does her skin.
Shes driven him away.
But why? There is a reason.
Shes pregnant.
Her home the South African Cape can get quite cold.
So instead of laying her eggs on the ground as most chameleons do she retains them within her body and warms them by seeking out the sunniest places and sunbathing.
Now theyre ready to emerge alive.
Producing babies in the branches might seem to be a risky business but the membrane enclosing each one will stick to a twig if it hits one.
And when at last the babies disentangle themselves they immediately deploy their formidable chameleon grip.
By the time they are properly dried out the babies are as much at home in the branches as their mother.
But for the most extraordinary chameleons of all you have to look not up in the trees but down here on the leaf litter.
A whole range of species live on the ground many of which have only recently been discovered.
This is surely the most extraordinary of all chameleons.
Its the pygmy leaf chameleon.
This is a male and hes fully grown believe it or not.
And yet within this tiny little body are all the anatomical details of a normal-sized chameleon.
What an extraordinary creature.
Like all chameleons it catches its food with its tongue.
(FLY BUZZING) It eats tiny flies.
Grasshoppers are popular with normal-sized chameleons.
The tongue contains a tapered rod encircled by muscle.
As the muscle contracts the tongue shoots forward off the rod.
The tip physically grasps the prey.
And then longitudinal muscles contract to pull the tongue back onto its rod bringing the prey with it which may weigh half as much as the chameleon itself.
The whole action in reality is completed in a second or so.
The canopy of a tropical forest is full of food and lizards clamber around looking for it in many ways.
Chameleons use their toes to grip the twigs and geckos use theirs to stick to leaves for their toes have adhesive pads on the ends.
Most geckos feed on insects but some take nectar from flowers.
And a few collect liquid from insects in much the same way as we take milk from cows.
The insect a treehopper is sitting head-down drinking sap from the tree.
It would be invisible were it not vibrating its abdomen.
And that is what the gecko wants from it a drop of honeydew.
Honeydew is what remains of tree sap after the hopper has extracted the protein from it.
Its very sweet and the gecko plainly loves it.
Other less colourful species of gecko also drink honeydew and some order it from the hopper by vibrating their heads.
The hopper tells the gecko that a drink is on the way by waggling its abdomen.
How the hopper benefits from this arrangement is not clear.
Perhaps the gecko keeps predatory insects away and the honeydew is protection money.
Most geckos are much less conspicuous and are very difficult to see.
Its the Madagascan leaf-tailed gecko.
And its tail has wide flanges on either side so that it has become leaf-shaped.
But these arent the only flanges.
It has also got them all round its toes its legs and down its flank.
And the consequence is that if it presses itself close to the bark and spreads those frills it sheds no shadow at all.
The irises of its eye are also part of this amazing camouflage.
They have a kind of mottled pale surface which makes them look exactly like one of these little blotches of lichen on the bark.
All in all its a most extraordinary disguise.
It and indeed the majority of geckos only really become active at night.
Here in Bangkok as in cities throughout the tropics geckos have discovered that mankinds lights attract a great banquet of insects.
As a result almost every building has its own resident gecko population.
(PEOPLE CHATTERING) Lizards for the most part are not known for being caring parents but there are exceptions.
Its spring in the woodlands of North America.
An American robin is nesting warming her eggs with the heat generated by her own body.
And below on the forest floor a five-lined skink is warming her cold-blooded body by basking in the sunshine so that she can do the same thing.
She has a nest below the log.
It can get quite chilly in these woodlands and she warms her eggs by transferring to them the heat that she has collected from the sun.
She takes just as much care of her eggs as the robin does.
A month later and her eggs are hatching.
The robins eggs have hatched too.
Her nestlings are helpless and need constant feeding.
The young skinks however are already capable of finding food for themselves.
Within a day or so theyve left their mother and are independently exploring the woodland floor for themselves.
But there are other skinks whose family life lasts rather longer.
These fields in South Australia are home to a little lizard that is so rare that it had been thought to be extinct for over 30 years until it was rediscovered in 1 992.
And the equipment you need to find it is believe it or not a fishing rod.
Now lets see if I can tempt him out with this.
(LAUGHING) Oh.
Thats got Gosh.
Now come up a little farther so we can see what you look like.
That is a very rare little creature.
Its a pygmy blue-tongued skink.
And it lives in the holes that are made by trapdoor spiders.
And this one is clearly very hungry.
Come on come on.
Wont you come out a little more? Come on.
just show us.
(EXCLAIMS) (LAUGHING) It won.
Lets have a closer look.
I can do that with this optical probe with its viewing screen on the end.
Its quite a long way down.
There he is all safe and snug.
And he really is safe down here.
Even a bush fire sweeping by wouldnt harm him.
And of course this explains why no one has seen these little lizards for so long.
Theyre very difficult to find.
But whats really special about this little lizard is its family life.
just look at these shots that we got with that optical probe.
That is a close-up of an adults head.
And there just beside her head is a tiny little head of a baby.
Thats one.
And if we push past her theres the baleful look of Mum who doesnt appreciate this.
And beyond two.
Two more babies.
So thats three.
Quite a crowded little home.
So there they are a nice little lizard family.
And the babies will stay in that crowded hole for three weeks or so before theyre ready to be able to go out into the outside world and look for a spiders burrow for themselves.
Theres another skink here whose family relationships last for decades.
This is a shingleback or as its called here in its home in Australia a sleepy lizard.
And its really quite a baffling creature because its head and its tail look very similar.
Maybe that confuses a predator.
But if you get closer it quickly shows which end is which by threatening with this gape display.
(LAUGHING) Oh.
Youre very perky.
And I have to be reasonably careful because it can bite.
But at this time of the year in the spring it also has another rather more gentle side to its character.
There.
Ill let you get on with it.
A female catches the eye of a male.
He starts to follow her wherever she goes.
Couples stay side by side for up to two months.
He courts her by gently nudging and licking her.
Six months pass.
And then eventually the results of this prolonged courtship begin to arrive.
Its a long and strenuous business for a mother shingleback.
She produces not a small egg like the five-lined skink but a live baby.
Its a whopper.
And theres another one to come.
Together the two weigh as much as a third of her body weight the equivalent in human beings of carrying a 3-year-old child.
Like the Cape chameleon in South Africa the female has been acting as a mobile incubator seeking out the warmest spots she can find in order to bask.
Producing such well-developed young is the shinglebacks response to the fact that it can get quite cold in South Australia.
Her young are so advanced that they soon leave her.
But when spring returns the same male and female will once again seek one another out and mate again.
In fact a pair will remain faithful to one another for as long as 20 years or more.
The bond between them may even endure after death.
Theyre slow-moving creatures and only too often when crossing a road theyre unable to get out of the way of a passing car.
If one of the pair is run over the other will often remain at its side for days tenderly nudging it.
You might even say that it was grieving.
On the other side of the world there are lizards with a very different lifestyle.
They gather together in groups with densities higher than you can find anywhere else.
And the reason they are able to do so you can see alongside the waters of this the Orange River in South Africa.
The river is the breeding ground for vast swarms of black flies.
Excellent food for a lizard if it can catch them.
In the early morning the Augrabies flat lizards emerge from the cracks in the rocks where they spent the night and bask in the sun to warm up.
The males are the brightly coloured ones as you can see from his marvellous blue head.
But its not his head that impresses his rivals so much.
Its the underside which if he is a high-status male will be bright orange and yellow.
And if another one turns up he will try and impress his rival by exposing that.
These awkward-looking postures reveal why these creatures are called flat lizards.
By regularly displaying their vivid badges the males repeatedly confirm their place in the pecking order and so keep fighting to a minimum.
As a female moves from one territory to another so each male courts her in turn.
And now theyre really warmed up and active and whole groups of them are beginning to travel down across the rocks towards the river where theyll find their food.
But down here where the flies swarm its a free-for-all.
And that causes a lot of trouble.
Catching flies is necessarily an acrobatic business.
But you cant leap for flies and still keep properly spaced out.
So there are inevitably quarrels between rival males.
Females on the other hand are only interested in getting a good meal.
Fired-up males however have other ideas.
For them there is more to life than just dinner.
And some wont take no for an answer.
The females want food.
They need a square meal to nourish the eggs that are developing within them.
But they wont get any peace until they leave the restaurant and get back home where life is better regulated.
The high-octane social life of the flat lizards with its constant squabbling seems to be very stressful but for other lizards fighting is less frequent but altogether more impressive.
A Mexican beaded lizard.
One of the few lizards in the world with a poisonous bite.
And a very virulent one it is too.
In the spring rival males fight according to a very specific set of rules.
They use neither their sharp powerful claws nor their poisonous bite in their battles.
At first they grapple rather warily to assess each others strength.
Then they begin to wrestle in earnest each trying to pin down the other on the ground.
These two are evenly matched.
Neither can get the crucial throw.
Its rather like an arm-wrestling contest and the bout can continue for several hours.
The eventual winner is the one who ends up on top most frequently.
Its a controlled test of strength in which despite their lethal weaponry no one gets seriously hurt.
Other lizards defend themselves not with physical strength but by deceit.
The South African desert.
A bushveld lizard.
This is another.
It looks very different but that is because its a baby.
It not only has different coloration it also walks in a very different and quite extraordinary way.
It appears to be imitating one of the local beetles - that one.
And to discover why Im going to take defensive measures with these goggles.
This beetle is known as an oogpister an eye-spitter.
Thats because its squirting formic acid at me.
Oh yeah and if any of that got into my eye it would be extremely painful.
Its a defensive system and the lizards are benefiting by imitating a beetle with that kind of armoury.
A young lizard closely matches the beetle both in its appearance and its walk so birds that prey on lizards assume it has a nasty spray and leave it alone.
Lizards can cope with dry hot conditions so well that they dominate the fauna in tropical deserts around the world including those in central Australia.
Their tough scaly skins prevent their bodies from losing moisture so that they can flourish in these arid baking-hot lands that other animals find so testing.
Some wear the most elaborate suits of armour.
This is surely the most enchanting of lizards.
It is called the thorny devil or Moloch after Moloch the god in the Bible who ate little children.
Both names surely are a slander on such an engaging little animal.
It feeds entirely on ants and as you can see theres not much of a meal in any one of them.
But the good thing about ants as far as Moloch is concerned is that theres always some around.
And this little creature will sit by an ant trail patiently for hours on end simply picking off one ant at a time.
The Australian desert is also home to one of the most powerful of the family.
Monitors are the kings of lizards.
And this is the perentie the biggest species of monitor in Australia.
It can grow up to two metres long six feet and its a highly intelligent animal.
It has got very acute senses of sight and hearing and taste and smell.
And like all monitors it can do something no other kind of lizard can do.
It can run continuously for a very long time and that enables it to become an endurance hunter chasing down its prey.
Most lizards inflate their lungs using the same muscles as they use for walking so they cant run and breathe effectively at the same time.
But monitors have big muscular throats which they use like bellows to pump air into their lungs and they can do that even when theyre running.
This special way of breathing enables them to reach speeds of over 20 miles an hour.
Over distance they are one of the fastest of all reptiles.
The cold-blooded perentie can even outrun a warm-blooded rabbit.
So the lizards have colonised the world from swamps to rainforests from woodland to desert.
And in doing so theyve revealed such a variety of form and behaviour that they truly can be called the dragons of the dry.
Much of our filming for this programme was done in Australia.
There there are lizards everywhere.
just walk around in the bush and youll see them.
But usually you wont get much more than a brief glimpse.
To film their intimate behaviour we needed help from experts.
We had travelled to Australia to meet an expert called Mike Bull.
He knows Australian lizards as well as anyone.
He and his team study many species in one small area north of Adelaide using all manner of gadgets and gizmos to investigate every part of their lives.
(BEEPING) We were particularly interested in the lizards that Mike understands best of all the shingleback or sleepy lizard.
He knows 1 0000 of them individually.
On the face of it the sleepy lizard doesnt seem to do a lot.
But Mike knows so much about them that we were able to make them one of the stars of our film.
Hes discovered that theyre the only lizards in the world that remain faithful to one partner for all their lives.
But that wasnt the reason that he began to study them.
Tell me first how you first saw sleepy lizards and what attracted you to them.
I first started because I was interested in parasites that live on the lizard.
To find the parasites I actually had to look at the lizards as well and I discovered they were doing things that were more interesting than the parasites.
And for me I think theyre one of the most handsome animals that youll ever find.
The other thing is that its probably the only animal that you know if youre driving along in a car and you see one 1 00 metres down the road you know youve caught it.
And its also one that I think Im going to be sufficiently agile to keep on catching until Im well past 80.
(BOTH LAUGHING) I might have to Even I I think could scrag a sleepy lizard.
Ill see whether I can manage it.
Sleepy lizards like to bask on warm roads so theyre easy to find and they move so slowly theyre easy to pick up.
So the team were able to weigh and measure a whole population and thus discovered that pairs remain together in a way that was previously known only in birds and mammals.
But that was just the start.
Next they turned to technology some of it advanced some a little bizarre.
They used remotely controlled rubber sleepy lizards to test how lizards reacted to one another.
In this case not very much.
Mikes team suspected theres another lizard in the area.
The gidgee skink had an even more complex social life.
But this was difficult to prove because when approached the skinks wedged themselves in cracks in the rocks making it impossible to identify whos who.
The solution was to microchip each lizard so it could then be scanned just like your supermarket shopping with a barcode reader on the end of a pole.
(BEEPS) This clever use of technology revealed what looked like a jumble of lizards on a pile of rocks to be actually a little lizard family with young that stay with their parents for life.
Im sure that there are going to be many other complex social organisations that will be uncovered in those species if we just simply take the time to look at them.
But its just the time and the patience to watch them.
And watching a lizard is very unrewarding because they will come out and bask and sit by a bush.
And if they see youre there then theyll decide theyre not going to do very much for the rest of the day.
ATTENBOROUGH: To find out just what sleepy lizards get up to when no ones around Mikes team use a rather bizarre device they call a waddleometer.
It may look a little odd but it records the lizards GPS coordinates counts its steps and even notes whether its in sun or shade all without troubling the lizard and without anyone having to be there.
So you think theres probably the secret world of the lizard which no human being has ever seen because if a human being is there the lizard wont behave that way? Im sure thats part of it.
Its the uncertainty principle.
The closer you get to watch something the less normally its behaving.
And so its only by getting these remote and new technologies that allow us to really get into the secret world of the lizards that we can find these really amazing things that theyre doing.
How extraordinary.
One of their latest techniques uses miniature cameras which they use to study a very special lizard that we were also particularly keen to film.
Its so rare that it was thought to be extinct for over 30 years until it was thrust back into the public eye when it was discovered in some very unusual circumstances.
There was a group of biologists who were doing a standard biological survey.
They were just coming back to town to pick up supplies and just on the road they saw a dead brown snake.
Now most people just wouldnt even look at it because theyre so common around here but these were dedicated biologists.
They stopped and had a look at it.
They noticed there was a bulge in it.
So they thought Lets see what its been eating.
Opened it up and there was this lizard that no one had seen for 30 years -a pygmy blue-tongued lizard.
-How lovely.
Though I dare say it wasnt all that lovely when they actually saw it.
Miniature cameras have produced images that are slowly helping to build up a comprehensive picture of the life of these rare little creatures.
Their burrows are more than just homes.
Theyre also hiding places where they can wait in ambush for spiders and crickets.
But they dont seem too keen on ants.
They also serve as bolt holes when danger approaches.
Despite all this work Mikes team had never recorded their life underground.
So we were able to help with a little of our own technology and record the first ever pictures of a pygmy blue-tongued family.
Three babies alongside their mother in their little hole.
But all this technology ingenious though it is is no substitute for years of dedicated observation.
Mikes approach of simply driving for miles across the Australian outback is very fruitful.
And you see lots of other things as well as lizards.
Up here is just a wonderful place for lizards -Oh boy.
-Yeah kangaroos.
-Eastern grey.
Beautiful wasnt it? -Yeah.
Now you wont catch a lizard doing that.
(BOTH CHUCKLING) BULL: Oh look theres a pair just down there.
It turned out that Mike had spotted two old friends.
This is the male and the female.
This is 1 1 72 and 3342.
I think theyve been together for about 1 0 years this pair.
-Really? -Weve got some other pairs that have been together for over 20 years.
They stay together during the springtime and they mate towards the end of the spring and then they separate.
But the next year the same two lizards well find them back together again usually in the same place along this road too.
ATTENBOROUGH: Arent they terrific? They use their tongues to pick up chemical signals and you can see theyre actually sensing each other at the moment.
I think thats really very touching.
(CHUCKLING) I say thats a risky business.
With obsessive dedication and ever-advancing technology who knows what Mike and his team will uncover about the secret lives of sleepy lizards?
They were to go one step further than the amphibians who had emerged onto dry land before them.
For they would eventually completely cut their ties with water.
They were the ancestors of todays lizards.
They evolved scaly impermeable skins and moved up into the forests.
They diversified into a multitude of different shapes and sizes.
They developed signalling systems to communicate with one another.
And they squabbled as animals do over mates and territory.
For food they hunted insects that were already well established on the land in great numbers.
And here without returning to water they produced their families.
They powered their bodies not only with food but with the heat that they drew directly from the sun.
As they diversified so they spread into the harshest of the lands habitats.
The baking waterless deserts which eventually they would come to dominate.
The bigger ones are truly powerful and fearless.
Rearing up theyre well able to defend themselves with their front legs if theyre threatened.
This is a very intelligent animal.
It is observing me just as I am observing it.
Its a monitor lizard and its king of this country the Australian outback.
It is frightened of pretty well nothing obviously including me and it will chase and hunt and eat pretty well anything.
There are several thousand lizards round the world and they are truly the dragons of the dry.
Their eggs on land had to be encased in shells to prevent them from drying out.
And what better place to lay them could a mother lizard find than a termites nest? Worker termites labour unceasingly to keep the temperature and humidity virtually constant for their own benefit.
But that also makes their mound a near-perfect incubator for eggs of others.
After 1 0 months theyre beginning to hatch.
These are baby lace monitors.
But they face a major problem.
A termite nests walls can be a foot thick and extremely hard too hard for the young monitors to break through.
They are imprisoned with no food.
For a week after hatching theyre sustained by the last of the yolk that remains in their stomachs.
But when that comes to an end they could starve.
An adult lace monitor is nearby.
It may or may not be the babies mother.
If not then it could be a threat for monitors are hunters and will eat most small animals including baby lizards.
Shes nearing the termite nest within which the young are trapped.
She could be looking for a place to lay her eggs.
Alternatively she might be searching for food such as little lizards.
The babies are released unharmed.
Perhaps she is indeed the babies mother and not only remembered exactly where she laid her eggs a year ago but knew that her babies would need her help to escape from the incubator.
The young however are free.
But the outside world is a dangerous place.
They head for safety up into the trees.
In the branches there are other kinds of lizards.
jacky dragons.
Each has its own territory and warns others to keep out.
A wave of the front leg and a bob of the head is a jacky dragons way of claiming territory.
Here the action is slowed down.
In reality the leg flick is so swift its hard for us to see but its very plain to another jacky dragon.
But sometimes signals are not enough.
Physical violence is needed.
Hes won.
The vanquished acknowledges his defeat with a different signal a slow leg wave with no head bob.
The winner returns to his territory in the branches and announces his victory which his neighbour acknowledges.
So now both can live alongside one another in peace.
Once jacky dragons stop signalling it is quite hard to spot them up in the branches.
American anoles are so well camouflaged theyre virtually invisible.
Theres one on this tree right in front of me.
But he too needs to draw attention to himself to warn off rivals and then to disappear from predators.
This mirror may persuade him to reveal his solution to the problem.
Now then what do you think of that? Whos that? Yes its a rival.
A tail wag.
Yes.
(LAUGHING) Youre not going to get rid of me that way.
Show us your signals.
Well press-ups certainly is a keep-away challenge.
And there.
Thats it.
The full works.
(LAUGHING) Ah.
Lovely.
Once more.
Thank you.
And again.
(LAUGHING) Come on.
He obviously thinks that his position is being contested and he is displaying to show that he is as good as anybody else.
So I guess Ill leave him in peace.
An anoles throat flap appears for only a second or so and then vanishes.
And its owner after sending his message returns to camouflaged obscurity.
Another family of lizards living in the treetops has an even more varied repertoire of signals.
They use not only gestures but body colours.
Theyre chameleons.
Their stronghold is the island of Madagascar.
And here there are over 60 different species of them almost more than in all the rest of the world put together.
This is a panther chameleon.
And its marvellously adapted for life among the branches.
Its toes are divided into two bundles three and two.
And that means that it can use them just like forceps.
Their grasping feet supplemented by their gripping tail enable them to become remarkable slow-motion acrobats.
I suppose chameleons are best known for their ability to change colour and that does help in camouflage.
But actually they also use colour change as a way of communication and expressing their emotions.
When a male panther chameleon spots a rival he expresses his fury in glorious technicolor.
Malawi in central Africa may not have as many species of chameleon as Madagascar but it has one of the largest Mellers chameleon that can be 60 centimetres nearly two feet from nose to tail.
Rival males when they do battle deploy a range of threats that is truly formidable.
If signals dont deter then they start to joust.
Its not only males that fight.
There are also battles between the sexes.
This is the South African dwarf chameleon.
A male in full courtship costume.
This somewhat less colourful is a female.
She is not welcoming his advances.
As her mood darkens so does her skin.
Shes driven him away.
But why? There is a reason.
Shes pregnant.
Her home the South African Cape can get quite cold.
So instead of laying her eggs on the ground as most chameleons do she retains them within her body and warms them by seeking out the sunniest places and sunbathing.
Now theyre ready to emerge alive.
Producing babies in the branches might seem to be a risky business but the membrane enclosing each one will stick to a twig if it hits one.
And when at last the babies disentangle themselves they immediately deploy their formidable chameleon grip.
By the time they are properly dried out the babies are as much at home in the branches as their mother.
But for the most extraordinary chameleons of all you have to look not up in the trees but down here on the leaf litter.
A whole range of species live on the ground many of which have only recently been discovered.
This is surely the most extraordinary of all chameleons.
Its the pygmy leaf chameleon.
This is a male and hes fully grown believe it or not.
And yet within this tiny little body are all the anatomical details of a normal-sized chameleon.
What an extraordinary creature.
Like all chameleons it catches its food with its tongue.
(FLY BUZZING) It eats tiny flies.
Grasshoppers are popular with normal-sized chameleons.
The tongue contains a tapered rod encircled by muscle.
As the muscle contracts the tongue shoots forward off the rod.
The tip physically grasps the prey.
And then longitudinal muscles contract to pull the tongue back onto its rod bringing the prey with it which may weigh half as much as the chameleon itself.
The whole action in reality is completed in a second or so.
The canopy of a tropical forest is full of food and lizards clamber around looking for it in many ways.
Chameleons use their toes to grip the twigs and geckos use theirs to stick to leaves for their toes have adhesive pads on the ends.
Most geckos feed on insects but some take nectar from flowers.
And a few collect liquid from insects in much the same way as we take milk from cows.
The insect a treehopper is sitting head-down drinking sap from the tree.
It would be invisible were it not vibrating its abdomen.
And that is what the gecko wants from it a drop of honeydew.
Honeydew is what remains of tree sap after the hopper has extracted the protein from it.
Its very sweet and the gecko plainly loves it.
Other less colourful species of gecko also drink honeydew and some order it from the hopper by vibrating their heads.
The hopper tells the gecko that a drink is on the way by waggling its abdomen.
How the hopper benefits from this arrangement is not clear.
Perhaps the gecko keeps predatory insects away and the honeydew is protection money.
Most geckos are much less conspicuous and are very difficult to see.
Its the Madagascan leaf-tailed gecko.
And its tail has wide flanges on either side so that it has become leaf-shaped.
But these arent the only flanges.
It has also got them all round its toes its legs and down its flank.
And the consequence is that if it presses itself close to the bark and spreads those frills it sheds no shadow at all.
The irises of its eye are also part of this amazing camouflage.
They have a kind of mottled pale surface which makes them look exactly like one of these little blotches of lichen on the bark.
All in all its a most extraordinary disguise.
It and indeed the majority of geckos only really become active at night.
Here in Bangkok as in cities throughout the tropics geckos have discovered that mankinds lights attract a great banquet of insects.
As a result almost every building has its own resident gecko population.
(PEOPLE CHATTERING) Lizards for the most part are not known for being caring parents but there are exceptions.
Its spring in the woodlands of North America.
An American robin is nesting warming her eggs with the heat generated by her own body.
And below on the forest floor a five-lined skink is warming her cold-blooded body by basking in the sunshine so that she can do the same thing.
She has a nest below the log.
It can get quite chilly in these woodlands and she warms her eggs by transferring to them the heat that she has collected from the sun.
She takes just as much care of her eggs as the robin does.
A month later and her eggs are hatching.
The robins eggs have hatched too.
Her nestlings are helpless and need constant feeding.
The young skinks however are already capable of finding food for themselves.
Within a day or so theyve left their mother and are independently exploring the woodland floor for themselves.
But there are other skinks whose family life lasts rather longer.
These fields in South Australia are home to a little lizard that is so rare that it had been thought to be extinct for over 30 years until it was rediscovered in 1 992.
And the equipment you need to find it is believe it or not a fishing rod.
Now lets see if I can tempt him out with this.
(LAUGHING) Oh.
Thats got Gosh.
Now come up a little farther so we can see what you look like.
That is a very rare little creature.
Its a pygmy blue-tongued skink.
And it lives in the holes that are made by trapdoor spiders.
And this one is clearly very hungry.
Come on come on.
Wont you come out a little more? Come on.
just show us.
(EXCLAIMS) (LAUGHING) It won.
Lets have a closer look.
I can do that with this optical probe with its viewing screen on the end.
Its quite a long way down.
There he is all safe and snug.
And he really is safe down here.
Even a bush fire sweeping by wouldnt harm him.
And of course this explains why no one has seen these little lizards for so long.
Theyre very difficult to find.
But whats really special about this little lizard is its family life.
just look at these shots that we got with that optical probe.
That is a close-up of an adults head.
And there just beside her head is a tiny little head of a baby.
Thats one.
And if we push past her theres the baleful look of Mum who doesnt appreciate this.
And beyond two.
Two more babies.
So thats three.
Quite a crowded little home.
So there they are a nice little lizard family.
And the babies will stay in that crowded hole for three weeks or so before theyre ready to be able to go out into the outside world and look for a spiders burrow for themselves.
Theres another skink here whose family relationships last for decades.
This is a shingleback or as its called here in its home in Australia a sleepy lizard.
And its really quite a baffling creature because its head and its tail look very similar.
Maybe that confuses a predator.
But if you get closer it quickly shows which end is which by threatening with this gape display.
(LAUGHING) Oh.
Youre very perky.
And I have to be reasonably careful because it can bite.
But at this time of the year in the spring it also has another rather more gentle side to its character.
There.
Ill let you get on with it.
A female catches the eye of a male.
He starts to follow her wherever she goes.
Couples stay side by side for up to two months.
He courts her by gently nudging and licking her.
Six months pass.
And then eventually the results of this prolonged courtship begin to arrive.
Its a long and strenuous business for a mother shingleback.
She produces not a small egg like the five-lined skink but a live baby.
Its a whopper.
And theres another one to come.
Together the two weigh as much as a third of her body weight the equivalent in human beings of carrying a 3-year-old child.
Like the Cape chameleon in South Africa the female has been acting as a mobile incubator seeking out the warmest spots she can find in order to bask.
Producing such well-developed young is the shinglebacks response to the fact that it can get quite cold in South Australia.
Her young are so advanced that they soon leave her.
But when spring returns the same male and female will once again seek one another out and mate again.
In fact a pair will remain faithful to one another for as long as 20 years or more.
The bond between them may even endure after death.
Theyre slow-moving creatures and only too often when crossing a road theyre unable to get out of the way of a passing car.
If one of the pair is run over the other will often remain at its side for days tenderly nudging it.
You might even say that it was grieving.
On the other side of the world there are lizards with a very different lifestyle.
They gather together in groups with densities higher than you can find anywhere else.
And the reason they are able to do so you can see alongside the waters of this the Orange River in South Africa.
The river is the breeding ground for vast swarms of black flies.
Excellent food for a lizard if it can catch them.
In the early morning the Augrabies flat lizards emerge from the cracks in the rocks where they spent the night and bask in the sun to warm up.
The males are the brightly coloured ones as you can see from his marvellous blue head.
But its not his head that impresses his rivals so much.
Its the underside which if he is a high-status male will be bright orange and yellow.
And if another one turns up he will try and impress his rival by exposing that.
These awkward-looking postures reveal why these creatures are called flat lizards.
By regularly displaying their vivid badges the males repeatedly confirm their place in the pecking order and so keep fighting to a minimum.
As a female moves from one territory to another so each male courts her in turn.
And now theyre really warmed up and active and whole groups of them are beginning to travel down across the rocks towards the river where theyll find their food.
But down here where the flies swarm its a free-for-all.
And that causes a lot of trouble.
Catching flies is necessarily an acrobatic business.
But you cant leap for flies and still keep properly spaced out.
So there are inevitably quarrels between rival males.
Females on the other hand are only interested in getting a good meal.
Fired-up males however have other ideas.
For them there is more to life than just dinner.
And some wont take no for an answer.
The females want food.
They need a square meal to nourish the eggs that are developing within them.
But they wont get any peace until they leave the restaurant and get back home where life is better regulated.
The high-octane social life of the flat lizards with its constant squabbling seems to be very stressful but for other lizards fighting is less frequent but altogether more impressive.
A Mexican beaded lizard.
One of the few lizards in the world with a poisonous bite.
And a very virulent one it is too.
In the spring rival males fight according to a very specific set of rules.
They use neither their sharp powerful claws nor their poisonous bite in their battles.
At first they grapple rather warily to assess each others strength.
Then they begin to wrestle in earnest each trying to pin down the other on the ground.
These two are evenly matched.
Neither can get the crucial throw.
Its rather like an arm-wrestling contest and the bout can continue for several hours.
The eventual winner is the one who ends up on top most frequently.
Its a controlled test of strength in which despite their lethal weaponry no one gets seriously hurt.
Other lizards defend themselves not with physical strength but by deceit.
The South African desert.
A bushveld lizard.
This is another.
It looks very different but that is because its a baby.
It not only has different coloration it also walks in a very different and quite extraordinary way.
It appears to be imitating one of the local beetles - that one.
And to discover why Im going to take defensive measures with these goggles.
This beetle is known as an oogpister an eye-spitter.
Thats because its squirting formic acid at me.
Oh yeah and if any of that got into my eye it would be extremely painful.
Its a defensive system and the lizards are benefiting by imitating a beetle with that kind of armoury.
A young lizard closely matches the beetle both in its appearance and its walk so birds that prey on lizards assume it has a nasty spray and leave it alone.
Lizards can cope with dry hot conditions so well that they dominate the fauna in tropical deserts around the world including those in central Australia.
Their tough scaly skins prevent their bodies from losing moisture so that they can flourish in these arid baking-hot lands that other animals find so testing.
Some wear the most elaborate suits of armour.
This is surely the most enchanting of lizards.
It is called the thorny devil or Moloch after Moloch the god in the Bible who ate little children.
Both names surely are a slander on such an engaging little animal.
It feeds entirely on ants and as you can see theres not much of a meal in any one of them.
But the good thing about ants as far as Moloch is concerned is that theres always some around.
And this little creature will sit by an ant trail patiently for hours on end simply picking off one ant at a time.
The Australian desert is also home to one of the most powerful of the family.
Monitors are the kings of lizards.
And this is the perentie the biggest species of monitor in Australia.
It can grow up to two metres long six feet and its a highly intelligent animal.
It has got very acute senses of sight and hearing and taste and smell.
And like all monitors it can do something no other kind of lizard can do.
It can run continuously for a very long time and that enables it to become an endurance hunter chasing down its prey.
Most lizards inflate their lungs using the same muscles as they use for walking so they cant run and breathe effectively at the same time.
But monitors have big muscular throats which they use like bellows to pump air into their lungs and they can do that even when theyre running.
This special way of breathing enables them to reach speeds of over 20 miles an hour.
Over distance they are one of the fastest of all reptiles.
The cold-blooded perentie can even outrun a warm-blooded rabbit.
So the lizards have colonised the world from swamps to rainforests from woodland to desert.
And in doing so theyve revealed such a variety of form and behaviour that they truly can be called the dragons of the dry.
Much of our filming for this programme was done in Australia.
There there are lizards everywhere.
just walk around in the bush and youll see them.
But usually you wont get much more than a brief glimpse.
To film their intimate behaviour we needed help from experts.
We had travelled to Australia to meet an expert called Mike Bull.
He knows Australian lizards as well as anyone.
He and his team study many species in one small area north of Adelaide using all manner of gadgets and gizmos to investigate every part of their lives.
(BEEPING) We were particularly interested in the lizards that Mike understands best of all the shingleback or sleepy lizard.
He knows 1 0000 of them individually.
On the face of it the sleepy lizard doesnt seem to do a lot.
But Mike knows so much about them that we were able to make them one of the stars of our film.
Hes discovered that theyre the only lizards in the world that remain faithful to one partner for all their lives.
But that wasnt the reason that he began to study them.
Tell me first how you first saw sleepy lizards and what attracted you to them.
I first started because I was interested in parasites that live on the lizard.
To find the parasites I actually had to look at the lizards as well and I discovered they were doing things that were more interesting than the parasites.
And for me I think theyre one of the most handsome animals that youll ever find.
The other thing is that its probably the only animal that you know if youre driving along in a car and you see one 1 00 metres down the road you know youve caught it.
And its also one that I think Im going to be sufficiently agile to keep on catching until Im well past 80.
(BOTH LAUGHING) I might have to Even I I think could scrag a sleepy lizard.
Ill see whether I can manage it.
Sleepy lizards like to bask on warm roads so theyre easy to find and they move so slowly theyre easy to pick up.
So the team were able to weigh and measure a whole population and thus discovered that pairs remain together in a way that was previously known only in birds and mammals.
But that was just the start.
Next they turned to technology some of it advanced some a little bizarre.
They used remotely controlled rubber sleepy lizards to test how lizards reacted to one another.
In this case not very much.
Mikes team suspected theres another lizard in the area.
The gidgee skink had an even more complex social life.
But this was difficult to prove because when approached the skinks wedged themselves in cracks in the rocks making it impossible to identify whos who.
The solution was to microchip each lizard so it could then be scanned just like your supermarket shopping with a barcode reader on the end of a pole.
(BEEPS) This clever use of technology revealed what looked like a jumble of lizards on a pile of rocks to be actually a little lizard family with young that stay with their parents for life.
Im sure that there are going to be many other complex social organisations that will be uncovered in those species if we just simply take the time to look at them.
But its just the time and the patience to watch them.
And watching a lizard is very unrewarding because they will come out and bask and sit by a bush.
And if they see youre there then theyll decide theyre not going to do very much for the rest of the day.
ATTENBOROUGH: To find out just what sleepy lizards get up to when no ones around Mikes team use a rather bizarre device they call a waddleometer.
It may look a little odd but it records the lizards GPS coordinates counts its steps and even notes whether its in sun or shade all without troubling the lizard and without anyone having to be there.
So you think theres probably the secret world of the lizard which no human being has ever seen because if a human being is there the lizard wont behave that way? Im sure thats part of it.
Its the uncertainty principle.
The closer you get to watch something the less normally its behaving.
And so its only by getting these remote and new technologies that allow us to really get into the secret world of the lizards that we can find these really amazing things that theyre doing.
How extraordinary.
One of their latest techniques uses miniature cameras which they use to study a very special lizard that we were also particularly keen to film.
Its so rare that it was thought to be extinct for over 30 years until it was thrust back into the public eye when it was discovered in some very unusual circumstances.
There was a group of biologists who were doing a standard biological survey.
They were just coming back to town to pick up supplies and just on the road they saw a dead brown snake.
Now most people just wouldnt even look at it because theyre so common around here but these were dedicated biologists.
They stopped and had a look at it.
They noticed there was a bulge in it.
So they thought Lets see what its been eating.
Opened it up and there was this lizard that no one had seen for 30 years -a pygmy blue-tongued lizard.
-How lovely.
Though I dare say it wasnt all that lovely when they actually saw it.
Miniature cameras have produced images that are slowly helping to build up a comprehensive picture of the life of these rare little creatures.
Their burrows are more than just homes.
Theyre also hiding places where they can wait in ambush for spiders and crickets.
But they dont seem too keen on ants.
They also serve as bolt holes when danger approaches.
Despite all this work Mikes team had never recorded their life underground.
So we were able to help with a little of our own technology and record the first ever pictures of a pygmy blue-tongued family.
Three babies alongside their mother in their little hole.
But all this technology ingenious though it is is no substitute for years of dedicated observation.
Mikes approach of simply driving for miles across the Australian outback is very fruitful.
And you see lots of other things as well as lizards.
Up here is just a wonderful place for lizards -Oh boy.
-Yeah kangaroos.
-Eastern grey.
Beautiful wasnt it? -Yeah.
Now you wont catch a lizard doing that.
(BOTH CHUCKLING) BULL: Oh look theres a pair just down there.
It turned out that Mike had spotted two old friends.
This is the male and the female.
This is 1 1 72 and 3342.
I think theyve been together for about 1 0 years this pair.
-Really? -Weve got some other pairs that have been together for over 20 years.
They stay together during the springtime and they mate towards the end of the spring and then they separate.
But the next year the same two lizards well find them back together again usually in the same place along this road too.
ATTENBOROUGH: Arent they terrific? They use their tongues to pick up chemical signals and you can see theyre actually sensing each other at the moment.
I think thats really very touching.
(CHUCKLING) I say thats a risky business.
With obsessive dedication and ever-advancing technology who knows what Mike and his team will uncover about the secret lives of sleepy lizards?