David Attenborough's Natural Curiosities (2013) s03e05 Episode Script
Curious Cures
1 The natural world is full of extraordinary animals, with amazing life histories.
Yet, certain stories are more intriguing than most.
The mysteries of a butterfly's life cycle, or the strange biology of the Emperor penguin.
Some of these creatures were surrounded by myth and misunderstandings, for a very long time.
And some, have only recently revealed their secrets.
These are the animals, that stand out from the crowd, The curiosities, I find particularly fascinating.
Some animals have intriguing ways, of protecting their skin.
The hippopotamus lives in Africa under the hot tropical sun, yet doesn't get sunburned.
And Capuchin monkeys live in insect infested jungles, but hardly ever get bitten.
How do these animals beat the elements, and protect themselves from sun, parasites and disease? Hippos are large land mammals, that can weigh up to 3 tonnes.
And they need to keep their huge bodies cool, and protected from the sun.
To avoid the heat, they spend much of the day swimming, as they are doing now, in the waters behind me.
But when they're on land,strangely, they don't appear to get sunburned.
The secret of their sun tolerance, lies within their skin.
It can sometimes appear shiny and greasy.
It has unique properties, that shocked the early explorers, and now excites modern scientists.
Hippos live in Africa, south of the Sahara, where temperatures can reach 40 degrees centigrade But they spend much of the day, submerged in rivers, lakes and swamps, and so avoid the worst of the sun's rays.
They possess formidable teeth, but they are in fact herbivores, and eat mostly grass, great quantities of it.
And they graze mostly at night.
Even so, continually moving in and out of water, together with being roasted, by the rays of the sun, could be very damaging to their skin.
But curiously, hippos remain healthy.
Throughout history, the hippopotamus has been the subject of many strange tales.
The Greeks claimed, they sweated blood.
And the Romans said, they deliberately pierced their skin on sharp rushes, to release blood.
It seems bizarre, that an animal would make itself bleed on purpose.
In the 19th century, one special hippopotamus allowed people to get a closer look at these strange skin secretions.
In 1849, the British Consul for Egypt, Charles Augustus Murray, formally requested that the Pasha of Egypt, helped capture a hippo, for the Zoological Society of London.
Hunters searched the reeds, on a remote island called Obaysch, 2,000 km up the Nile, from Cairo.
They discovered a male hippo, that was only a few days old.
When they tried to grab it, a strange thing happened.
Murray describes how a slimy exudation, lavishly poured forth, from the innumerable pores in the skin, rendering it so slippery, that the animal was impossible to hold.
The hunters dropped the baby hippo back into the waters of the Nile, but they managed to retrieve it again, using the hook of a spear.
The prize hippo was named Obaysch, after the island of its capture.
And here he is.
Before his capture, young Obaysch lived with his mother.
She had moved away from the herd, to give birth alone, and she protected him, from lions and crocodiles.
Whether Obaysch became accidentally separated from his mother, we'll never know.
But we do know, that secretions from his skin made him so slippery, that he very nearly escaped capture.
At this time, very little was known about hippos, and many people believed, that they were some kind of horse, that had taken, to living in rivers.
In the early 20th century, naturalists decided, that they were closely related to pigs.
DNA evidence however, now shows, that in fact their ancestors were cetaceans, the group that contains whales and dolphins.
So, hippos still retain many adaptations, for a life in water.
Hippos are very heavy animals, but for most of their time, their bodies are supported by water.
They're not really very good swimmers.
In the water, they move by bounding across the bottom.
They're well adapted to a semi-aquatic life, because their ears, their eyes and their nostrils are all towards the top of the head, which enables them to lie almost totally submerged, and yet still keep notice, of what's going on, on land.
But their skin, is almost entirely hairless.
So, on land it has to be kept moist.
In order to prevent young Obaysch, from sunburn and drying out, the Egyptian Pasha had a boat built, with a bathing pool, to transport Obaysch in comfort, all the way down the river Nile.
Accompanied by several cows, to supply him with milk, he arrived safely in Cairo, 4 months later On receiving Obaysch, the British consul wrote excitedly to the Zoological Society of London, confirming that the hippo was alive, and as tame and playful as a puppy.
But his travels were not yet over.
In the spring of 1850, Obaysch was taken to Alexandria, to board a P&O steamship, called the Ripon.
A special hippo house with a water tank, was built on the deck, and in May, Obaysch arrived safely in Southampton.
With the help of block and tackle, he was loaded onto a train, bound for London.
And at 10 o'clock at night, the tired hippo and his keeper, reached London Zoo.
His home was a newly constructed enclosure, complete with a heated swimming pool.
After many hours of traveling, the hippo gratefully plunged into the water.
Obaysch, the hippo sensation, had arrived.
A journey of over 5,000 miles, by sailboat, steamboat, and a train brought a hippo to England.
The first one, since Roman times.
Now Europeans had a chance to get close to this unusual creature, and perhaps learn more, about it's strange skin secretions.
Later, more hippos arrived at other zoos, and the blood-red sweat was seen again.
In the cooler climate of Europe, hippos don't sweat very much.
But zoo-keepers have reported, that sometimes in the morning, they see red trickles forming on the flanks or these animals.
It comes from particularly large pores, which form streaks on the animal's side, which does look, a little like blood.
We know for some time, that this is a moisturizer.
But why it's red, has only just been discovered.
A little more.
Come on.
There we go.
Recently, Japanese scientists were intrigued to see photos of a wild baby hippo, with light-pink skin, that still didn't burn under the harsh African sun.
They wondered, if the red secretion played a role, in protecting its pale skin.
So they collected hippo secretion, from captive hippos, to look at its composition.
They discovered two pigments.
A red one, that they named Hipposudoric Acid, and an orange one, that they called Norhipposudoric Acid.
The red pigment was found to absorb harmful wavelengths of light, and both pigments were anti-bacterial.
Here was the answer, to why hippos never got sunburned.
And why the wounds of battling males, rarely became infected.
The mysterious slime, is neither blood, nor sweat, but a specialized secretion, that turns red in sunlight, and protects the hippo's skin.
So, what became of Obaysch, the first ever hippo in captivity, that gave us a close-up view, of these curious creatures? For several years, he was the sensation of London Zoo.
He even inspired the Hippo Polka, a popular dance at its time.
But visitors grew weary of him.
Some were disappointed, not to see a giant river horse.
And others expected a ferocious beast, not a gentle giant.
Obaysch died in 1878, at the age of 28.
And he and others that followed, taught us some intriguing things about hippos, including the reason for the blood-red droplets, found on their skin.
So, hippos can produce their very own natural suncream, which is waterproof, moisturizing, and anti-bacterial.
Next, meet another animal, that also has its own curious cure.
The Capuchin monkey, that deals with biting insects in a particularly intriguing way.
The hippo produces a natural suncream, to prevent its skin from getting burned.
Capuchin monkeys also need to protect their skin, and do so, in a very surprising way.
When early explorers reached the Americas in the 15th century, they encountered small monkeys, with patches of dark-brown fur on their heads, that resembled hoods.
So they named them after a group of Franciscan friars, called Capuchin monks.
Capuchin monkeys, quickly charmed their way into our hearts.
With dextrous hands, and inquisitive personalities, they seemed very human-like.
They were also adept, at learning tricks.
And soon became popular performers, on our streets.
In the past, we used to teach monkeys, how to do things, how to perform tricks.
But things are different today.
Today, monkeys are teaching us things.
Watch what happens, when I give them a few spring onions, and some chili peppers.
They're clearly not eating, what I offered them.
They're rubbing themselves, with the peppers and the onions.
You might think they're nuts, because they're captive monkeys, and they are just doing that, to entertain themselves.
But not so.
I've seen capuchins do just that, in the wild.
These white-faced capuchins in Costa Rica, reacted in much the same way, when they came across a particular rainforest plant, the Piper plant.
These leaves have a distinctive liquorice scent, and they're hard to come by.
So, when they do find them, the monkeys pass the leaves among the troupe, so that everyone could have a share.
Both in the wild, and in captivity Capuchin monkeys become similarly excited, at the sight of lemons or limes.
And again, the same frenzied activity, and fur rubbing follows.
What is it about these plants, that gets the monkeys so excited? We know, they all give off a pungent smell, so could this be, what the capuchins are after? Smell plays an important part in the lives of many primates, but none more so, than in the lives of these lovely ring-tailed lemurs.
They use it, both, to establish their position within the troupe, and also the boundaries, the frontiers of their territory.
If you look at the inside of their forearms, there's a black patch, without fur.
And there, the skin is loaded with glands, that produce a very strong smell.
And when these boys go into battle.
.
oops! When they go into battle, they draw their furry tail to their forearms, loading it, with scent from those glands, and then, they wave it over their backs, in the direction of their enemies.
In a kind of stink fight.
You understand that, donât you? Oh! The pungent scent is also used by males, during the mating season.
This male, has rubbed his own distinctive smell onto his tail, and he now wafts it towards a female, to signal his intentions.
But she is not entirely convinced.
Unlike lemurs, capuchins don't have scent glands.
So, some thought, that they could be using the smell of certain plants, for communication.
But it turns out, that they have a different perfume for that job.
Urine.
Which they apply lavishly to their fur.
So why then, do they also anoint themselves with other smells? The answer may be found, in our own history.
The early Romans, noticed some 2,000 years ago, that the fruits and leaves of the lemon plant, have an exceptionally strong scent, that can be used to ward off insects.
A further clue, as to why capuchins might cover themselves, in such pungent smells, comes from this plant.
The piper plant.
Throughout the Amazon, Indian tribes apply it as an antiseptic on wounds.
And in Costa Rica, it's used as an insect repellent.
Could it be, that Capuchin monkeys protect themselves, against the onslaught of mosquitoes in much the same way as humans do, by rubbing themselves, with mosquito repellent? In 1993, scientists at Oxford University, decided to put the question to the test.
They collected some feather lice, and put them into Petri dishes overnight.
Into one dish, they also placed a slice of lime.
The next day, the lice, without the lime, were mostly alive.
Whilst in the other dish, two thirds had died, and the remainder were paralyzed.
Clearly, the lime contains a lethal insecticide.
Today, we know, that citrus fruit peel does indeed contain insecticides, which disrupts the nervous system of many small insects, causing them to become uncoordinated and paralyzed.
The leaves of the piper plant, are antiseptic, and contain substances, to protect against fungal and bacterial infection.
And chili pepper extract, is commonly used in households and gardens, to deter small mammals and insect pests.
So it seems, that the clever monkeys know exactly, how to make the best use of nature's remedies.
Recent researchers also revealed, that capuchins anoint themselves far more during the wet season, When mosquitoes are more abundant, and the risk of infection is higher.
Troupes use different plants, possibly, simply because they have to use, what's locally available.
But there's one substance with insect repellent qualities, that appeals to primates, including capuchins, that comes, not from a plant, but from an animal.
An animal .
.
like this.
A giant millipede.
When attacked, or in danger, tropical millipedes often produce a powerful, defensive secretion.
And black lemurs have worked out, how to use this to their advantage.
When they find a millipede, they give it a gentle bite to the head, to make it release its secretion, and then rub this through their fur.
The toxic fluid has a strong smell, and is highly irritating.
But it protects the lemurs against mosquitoes.
This pungent secretion, has apparently another strange effect.
It seems to act as a narcotic, sending the lemur into a kind of trance.
Like other drugs, it has powerful side effects.
We still don't understand how capuchins and lemurs select the plants, that they use for medicinal purposes.
These capuchins behind me, were born and raised in captivity, so they never encountered the plants, that their parents and ancestors would have used.
So, how do the monkeys know, which plants to choose? Can they detect particular substances in them? Or is it something, they learn from others? We don't yet know the answers, but it could be that babies learn by watching the adults, and that it's passed down the family line.
It's clearly a great, social event with everyone joining in.
And afterwards, the entire group appears to be more tightly bonded.
When Europeans first saw monkeys in the wild, they thought, that they were imitating, what people did, in some of their behaviours.
But quite the reverse.
It now turns out, that many of the local people did things that the monkeys had taught them.
Using plants as medicines.
So it seems, clever monkeys have taught us a trick or two.
So it's clear, that we are not alone in using medicines against injuries and infections.
Both Capuchin monkeys and hippos, discovered some medical remedies long before we did.
Yet, certain stories are more intriguing than most.
The mysteries of a butterfly's life cycle, or the strange biology of the Emperor penguin.
Some of these creatures were surrounded by myth and misunderstandings, for a very long time.
And some, have only recently revealed their secrets.
These are the animals, that stand out from the crowd, The curiosities, I find particularly fascinating.
Some animals have intriguing ways, of protecting their skin.
The hippopotamus lives in Africa under the hot tropical sun, yet doesn't get sunburned.
And Capuchin monkeys live in insect infested jungles, but hardly ever get bitten.
How do these animals beat the elements, and protect themselves from sun, parasites and disease? Hippos are large land mammals, that can weigh up to 3 tonnes.
And they need to keep their huge bodies cool, and protected from the sun.
To avoid the heat, they spend much of the day swimming, as they are doing now, in the waters behind me.
But when they're on land,strangely, they don't appear to get sunburned.
The secret of their sun tolerance, lies within their skin.
It can sometimes appear shiny and greasy.
It has unique properties, that shocked the early explorers, and now excites modern scientists.
Hippos live in Africa, south of the Sahara, where temperatures can reach 40 degrees centigrade But they spend much of the day, submerged in rivers, lakes and swamps, and so avoid the worst of the sun's rays.
They possess formidable teeth, but they are in fact herbivores, and eat mostly grass, great quantities of it.
And they graze mostly at night.
Even so, continually moving in and out of water, together with being roasted, by the rays of the sun, could be very damaging to their skin.
But curiously, hippos remain healthy.
Throughout history, the hippopotamus has been the subject of many strange tales.
The Greeks claimed, they sweated blood.
And the Romans said, they deliberately pierced their skin on sharp rushes, to release blood.
It seems bizarre, that an animal would make itself bleed on purpose.
In the 19th century, one special hippopotamus allowed people to get a closer look at these strange skin secretions.
In 1849, the British Consul for Egypt, Charles Augustus Murray, formally requested that the Pasha of Egypt, helped capture a hippo, for the Zoological Society of London.
Hunters searched the reeds, on a remote island called Obaysch, 2,000 km up the Nile, from Cairo.
They discovered a male hippo, that was only a few days old.
When they tried to grab it, a strange thing happened.
Murray describes how a slimy exudation, lavishly poured forth, from the innumerable pores in the skin, rendering it so slippery, that the animal was impossible to hold.
The hunters dropped the baby hippo back into the waters of the Nile, but they managed to retrieve it again, using the hook of a spear.
The prize hippo was named Obaysch, after the island of its capture.
And here he is.
Before his capture, young Obaysch lived with his mother.
She had moved away from the herd, to give birth alone, and she protected him, from lions and crocodiles.
Whether Obaysch became accidentally separated from his mother, we'll never know.
But we do know, that secretions from his skin made him so slippery, that he very nearly escaped capture.
At this time, very little was known about hippos, and many people believed, that they were some kind of horse, that had taken, to living in rivers.
In the early 20th century, naturalists decided, that they were closely related to pigs.
DNA evidence however, now shows, that in fact their ancestors were cetaceans, the group that contains whales and dolphins.
So, hippos still retain many adaptations, for a life in water.
Hippos are very heavy animals, but for most of their time, their bodies are supported by water.
They're not really very good swimmers.
In the water, they move by bounding across the bottom.
They're well adapted to a semi-aquatic life, because their ears, their eyes and their nostrils are all towards the top of the head, which enables them to lie almost totally submerged, and yet still keep notice, of what's going on, on land.
But their skin, is almost entirely hairless.
So, on land it has to be kept moist.
In order to prevent young Obaysch, from sunburn and drying out, the Egyptian Pasha had a boat built, with a bathing pool, to transport Obaysch in comfort, all the way down the river Nile.
Accompanied by several cows, to supply him with milk, he arrived safely in Cairo, 4 months later On receiving Obaysch, the British consul wrote excitedly to the Zoological Society of London, confirming that the hippo was alive, and as tame and playful as a puppy.
But his travels were not yet over.
In the spring of 1850, Obaysch was taken to Alexandria, to board a P&O steamship, called the Ripon.
A special hippo house with a water tank, was built on the deck, and in May, Obaysch arrived safely in Southampton.
With the help of block and tackle, he was loaded onto a train, bound for London.
And at 10 o'clock at night, the tired hippo and his keeper, reached London Zoo.
His home was a newly constructed enclosure, complete with a heated swimming pool.
After many hours of traveling, the hippo gratefully plunged into the water.
Obaysch, the hippo sensation, had arrived.
A journey of over 5,000 miles, by sailboat, steamboat, and a train brought a hippo to England.
The first one, since Roman times.
Now Europeans had a chance to get close to this unusual creature, and perhaps learn more, about it's strange skin secretions.
Later, more hippos arrived at other zoos, and the blood-red sweat was seen again.
In the cooler climate of Europe, hippos don't sweat very much.
But zoo-keepers have reported, that sometimes in the morning, they see red trickles forming on the flanks or these animals.
It comes from particularly large pores, which form streaks on the animal's side, which does look, a little like blood.
We know for some time, that this is a moisturizer.
But why it's red, has only just been discovered.
A little more.
Come on.
There we go.
Recently, Japanese scientists were intrigued to see photos of a wild baby hippo, with light-pink skin, that still didn't burn under the harsh African sun.
They wondered, if the red secretion played a role, in protecting its pale skin.
So they collected hippo secretion, from captive hippos, to look at its composition.
They discovered two pigments.
A red one, that they named Hipposudoric Acid, and an orange one, that they called Norhipposudoric Acid.
The red pigment was found to absorb harmful wavelengths of light, and both pigments were anti-bacterial.
Here was the answer, to why hippos never got sunburned.
And why the wounds of battling males, rarely became infected.
The mysterious slime, is neither blood, nor sweat, but a specialized secretion, that turns red in sunlight, and protects the hippo's skin.
So, what became of Obaysch, the first ever hippo in captivity, that gave us a close-up view, of these curious creatures? For several years, he was the sensation of London Zoo.
He even inspired the Hippo Polka, a popular dance at its time.
But visitors grew weary of him.
Some were disappointed, not to see a giant river horse.
And others expected a ferocious beast, not a gentle giant.
Obaysch died in 1878, at the age of 28.
And he and others that followed, taught us some intriguing things about hippos, including the reason for the blood-red droplets, found on their skin.
So, hippos can produce their very own natural suncream, which is waterproof, moisturizing, and anti-bacterial.
Next, meet another animal, that also has its own curious cure.
The Capuchin monkey, that deals with biting insects in a particularly intriguing way.
The hippo produces a natural suncream, to prevent its skin from getting burned.
Capuchin monkeys also need to protect their skin, and do so, in a very surprising way.
When early explorers reached the Americas in the 15th century, they encountered small monkeys, with patches of dark-brown fur on their heads, that resembled hoods.
So they named them after a group of Franciscan friars, called Capuchin monks.
Capuchin monkeys, quickly charmed their way into our hearts.
With dextrous hands, and inquisitive personalities, they seemed very human-like.
They were also adept, at learning tricks.
And soon became popular performers, on our streets.
In the past, we used to teach monkeys, how to do things, how to perform tricks.
But things are different today.
Today, monkeys are teaching us things.
Watch what happens, when I give them a few spring onions, and some chili peppers.
They're clearly not eating, what I offered them.
They're rubbing themselves, with the peppers and the onions.
You might think they're nuts, because they're captive monkeys, and they are just doing that, to entertain themselves.
But not so.
I've seen capuchins do just that, in the wild.
These white-faced capuchins in Costa Rica, reacted in much the same way, when they came across a particular rainforest plant, the Piper plant.
These leaves have a distinctive liquorice scent, and they're hard to come by.
So, when they do find them, the monkeys pass the leaves among the troupe, so that everyone could have a share.
Both in the wild, and in captivity Capuchin monkeys become similarly excited, at the sight of lemons or limes.
And again, the same frenzied activity, and fur rubbing follows.
What is it about these plants, that gets the monkeys so excited? We know, they all give off a pungent smell, so could this be, what the capuchins are after? Smell plays an important part in the lives of many primates, but none more so, than in the lives of these lovely ring-tailed lemurs.
They use it, both, to establish their position within the troupe, and also the boundaries, the frontiers of their territory.
If you look at the inside of their forearms, there's a black patch, without fur.
And there, the skin is loaded with glands, that produce a very strong smell.
And when these boys go into battle.
.
oops! When they go into battle, they draw their furry tail to their forearms, loading it, with scent from those glands, and then, they wave it over their backs, in the direction of their enemies.
In a kind of stink fight.
You understand that, donât you? Oh! The pungent scent is also used by males, during the mating season.
This male, has rubbed his own distinctive smell onto his tail, and he now wafts it towards a female, to signal his intentions.
But she is not entirely convinced.
Unlike lemurs, capuchins don't have scent glands.
So, some thought, that they could be using the smell of certain plants, for communication.
But it turns out, that they have a different perfume for that job.
Urine.
Which they apply lavishly to their fur.
So why then, do they also anoint themselves with other smells? The answer may be found, in our own history.
The early Romans, noticed some 2,000 years ago, that the fruits and leaves of the lemon plant, have an exceptionally strong scent, that can be used to ward off insects.
A further clue, as to why capuchins might cover themselves, in such pungent smells, comes from this plant.
The piper plant.
Throughout the Amazon, Indian tribes apply it as an antiseptic on wounds.
And in Costa Rica, it's used as an insect repellent.
Could it be, that Capuchin monkeys protect themselves, against the onslaught of mosquitoes in much the same way as humans do, by rubbing themselves, with mosquito repellent? In 1993, scientists at Oxford University, decided to put the question to the test.
They collected some feather lice, and put them into Petri dishes overnight.
Into one dish, they also placed a slice of lime.
The next day, the lice, without the lime, were mostly alive.
Whilst in the other dish, two thirds had died, and the remainder were paralyzed.
Clearly, the lime contains a lethal insecticide.
Today, we know, that citrus fruit peel does indeed contain insecticides, which disrupts the nervous system of many small insects, causing them to become uncoordinated and paralyzed.
The leaves of the piper plant, are antiseptic, and contain substances, to protect against fungal and bacterial infection.
And chili pepper extract, is commonly used in households and gardens, to deter small mammals and insect pests.
So it seems, that the clever monkeys know exactly, how to make the best use of nature's remedies.
Recent researchers also revealed, that capuchins anoint themselves far more during the wet season, When mosquitoes are more abundant, and the risk of infection is higher.
Troupes use different plants, possibly, simply because they have to use, what's locally available.
But there's one substance with insect repellent qualities, that appeals to primates, including capuchins, that comes, not from a plant, but from an animal.
An animal .
.
like this.
A giant millipede.
When attacked, or in danger, tropical millipedes often produce a powerful, defensive secretion.
And black lemurs have worked out, how to use this to their advantage.
When they find a millipede, they give it a gentle bite to the head, to make it release its secretion, and then rub this through their fur.
The toxic fluid has a strong smell, and is highly irritating.
But it protects the lemurs against mosquitoes.
This pungent secretion, has apparently another strange effect.
It seems to act as a narcotic, sending the lemur into a kind of trance.
Like other drugs, it has powerful side effects.
We still don't understand how capuchins and lemurs select the plants, that they use for medicinal purposes.
These capuchins behind me, were born and raised in captivity, so they never encountered the plants, that their parents and ancestors would have used.
So, how do the monkeys know, which plants to choose? Can they detect particular substances in them? Or is it something, they learn from others? We don't yet know the answers, but it could be that babies learn by watching the adults, and that it's passed down the family line.
It's clearly a great, social event with everyone joining in.
And afterwards, the entire group appears to be more tightly bonded.
When Europeans first saw monkeys in the wild, they thought, that they were imitating, what people did, in some of their behaviours.
But quite the reverse.
It now turns out, that many of the local people did things that the monkeys had taught them.
Using plants as medicines.
So it seems, clever monkeys have taught us a trick or two.
So it's clear, that we are not alone in using medicines against injuries and infections.
Both Capuchin monkeys and hippos, discovered some medical remedies long before we did.