(light dramatic music) (bugs chirping)
Anyone fascinated by the natural world
has probably wondered why some animals
have such strange looking sense organs.
The elephant with its huge ears,
the antennae of a butterfly,
which up close look like feathers,
the snake with its split tongue.
And what about less obvious enhancements
like the sensory cells on a crocodile's skin?
Surely these evolutionary traits aren't just for decoration.
In fact, the size, shape and location
of these animals sense organs is all for a purpose,
and just like us, animals rely on their senses
to communicate with each other,
find their way around, stay safe,
and most importantly, to find food.
When you see how superior some animal senses
are compared to those of humans,
you might wonder how we ever managed to stay
on top of the food chain.
"Animal Super Senses", you won't believe what's possible.
Throughout the natural world, individuals interact,
and sending and receiving information is vital for survival.
Animals use communication to attract mates,
ward off predators, defend territory, or trick their prey.
And of course, it's the senses that play the key role.
Sight, smell, taste, touch, and hearing,
are all employed to send signals to others
in the hope actions speak louder than words.
In this episode of "Animal Super Senses"
we find out more about the sensory powers used
by animals to make messages loud and clear.
Sun-baked Africa.
Many animals find sanctuary from
the heat in rivers and lakes.
To keep cool, hippos spend much
of their day wallowing in water.
Even with their bodies submerged,
the hippo can still see, hear and smell
what's going on around it.
Their epidermis is thin, with no sweat glands,
but they do secrete a red fluid,
giving rise to the myth that hippos sweat blood.
This secretion contains a sunscreen, an antiseptic,
and moistens delicate skin.
Large, slow and rotund, these amphibious giants
seem gentle and rather sleepy.
Yawning is major pastime.
(hippo yawns)
But looks are deceiving.
A large hippo guards his harem of females from sneaky males.
If provoked, he will show who is boss.
At 2,700 kilos, with formidable canines,
the alpha sends a clear message to would-be Romeos.
That's no sleepy yawn, it's a threat posture.
Their 50-centimeter long teeth can do some serious damage.
Even with the hippo's poor eyesight,
having a huge gap should get the point across.
But just in case the visual threat is ignored,
hippos send another warning.
This time, scent is used in a rather unique way.
Hippos have a great sense of smell,
a fact not lost in domain disputes.
As the hippo goes to the toilet,
it vigorously wags its tail, spreading poop far and wide.
Dung spraying is the hippo's way of marking its territory.
Breeding males fling feces at the competition
in hope that these smelly encounters will decide the winner
without resorting to a fight.
In the savanna of East Africa is another social species.
Baboons live in troops of related females,
offsprings of various ages, and several adult males.
Each individual has a rank with a dominant in charge.
They get the best resources first,
including access to the ladies.
(upbeat music)
But life at the top for the troop leader
is not all fun and games.
Every day there are pretenders to the throne looking
for mating rights.
Young virile males transfer
from other groups to find a mate.
These yawning threat postures send a strong visual message,
exaggerating the length of the canines.
But there are less aggressive ways of keeping your rank.
Grooming is used to make friends and influence others.
It's a communication tool that builds relationships
and maintains strong bonds.
This social sense of touch helps keep harmony in the group.
A world away, on a different continent,
things are heating up on a California beach.
These beach bums are northern elephant seals.
It's late November, and the breeding season has started.
Mature bulls have begun to arrive
with one thing on their mind.
(upbeat music)
(bulls squawking)
The males will fight to determine who will be dominant.
The winner's prize is a harem of blubber babes.
Rather ungainly on land, these tubs of fat
with pendulous noses can still pack a punch.
In the elephant seal world, size does matter.
The nose of a bull elephant seal starts to grow
at puberty and continues to grow with age.
It can reach two feet in length.
Fights between males can get bloody
and be surprisingly energetic.
A testosterone fueled fight has contenders rear up
and slam their bodies against each other.
The scars of past contests are clear to see on some bulls,
but efforts are made to avoid armed combat.
Throwing back their heads to show off
their enormous proboscis, the message is clear.
A visual signal to intimidate challengers.
And the nose has another function
to back up the menacing sight.
It's a sound chamber to amplify bellows.
The roar serves to identify individuals
and assess their size.
The bigger the nose, the bigger the bellow.
The alpha male, also known as the beach master,
roars his superiority.
Mating season on the beach can be a noisy affair.
Sight and sound are used to communicate dominance
in the elephant seal's world.
Thanks to the senses, conflicts are usually settled
without a deadly conclusion.
Another animal, where males flex their physical might
to attract the opposite sex, lives down under.
Twice the size of females, and with bulging biceps,
males show off in a bushland gym.
The gray kangaroo lives in semi-nomadic mobs.
Ranging throughout Australia, they prefer open grassland
with areas of bush for daytime shelter.
At dawn and dusk they come out to feed,
grazing on a wide variety of grasses.
Powerful back legs help them to travel at speeds
of up to 65 kilometers per hour with minimal effort.
During breeding season, males compete for females.
Young bucks test their strength with each other by sparring.
This ritualized fighting prepares them for adult life.
In fact, the social life of a mob
is akin to a bar room brawl with constant pushing,
grabbing and shoving, even while feeding.
This tactile behavior serves to communicate
their status in the mob.
But the real action is reserved for the adults.
It starts off with an aggressive grass pulling,
followed by the agitator rubbing their chests on the ground.
Kangaroos have an excellent sense of smell,
spreading the testosterone laced odor
is a way to threaten their rivals.
Scent marking is an important form
of communication in marsupials.
Studies have shown that social status
could affect odor composition and act
as a chemical fingerprint.
Muscle bound males enter wrestling and kickboxing contests.
They lock arms and try to push each other over.
The meter-long tail is used for support
when the back legs are lifted off
the ground to kick opponents.
It is a dominant male that gets to mate the most.
Physical displays matter in the kangaroo world,
not just to intimidate opponents,
but also to woo the ladies.
Lounging males of breeding age have been found
to strike a pose to show off their bulky biceps.
It's thought to be an effective strategy.
Research has shown that males with big muscles
are sexually selected for...
In other words, female kangaroos find
the hunkiest males sexy.
Koalas sleep. A lot.
In fact, for 20 hours a day, that's all they do.
Apart from the occasional itch that needs to be scratched,
but even then they don't wake up.
Their strict diet of eucalyptus provides little nourishment
and they need to conserve energy.
A very slow metabolic rate allows koalas to digest
their food over a long period of time
to make sure as much nutrition is extracted as possible.
Waking hours are spent chewing the fibrous leaves,
and getting enough nutrients is even more important
if you're eating for two.
Joeys are born after 35 days of gestation.
The tiny baby looks like a jelly bean and only
two centimeters long.
It's hairless, blind and has no ears,
but it makes its own way from the mother's
birth canal to her pouch.
Relying on its well-developed sense of smell and touch
to navigate to a teat.
The joey stays with its mom for a year
during which mothers and babies make soft clicking noises
and gentle humming sounds to one another.
Sensory communication strengthens bonds
between mother and young.
A life of eating and sleeping sounds idyllic,
and this tree-hugger seems gentle, placid,
and for all the world, like a cuddly bear.
But when the breeding season arrives in August
there's another much more active
and noisy side to koala life.
The koala's keen sense of hearing is put
to good use in the eucalypt forest.
Males issue sounds with a mixture
of grunting, burping bellows.
The noise is 20 times lower in pitch
than the koala should be able to produce.
A fact that has baffled researchers.
But recent studies have found the answer.
Koalas have two sets of vocal chords,
unlike any other land mammal.
The deep resonating calls of male koalas
can penetrate far across the forest,
advertising his social and physical position to females.
Koalas are mostly solitary and avoid
interactions where possible.
Male koalas have home ranges that stretch over four acres.
Some of these territories may overlap.
A mature male has a gland on his chest that secretes
a dark sticky substance.
He rubs the odor on trees in the overlapping areas.
In this way, koalas use the sense of smell
to communicate their presence to rival males
by scent marking their boundaries.
When it comes to mating rituals and courtship,
birds can out do mammals by sheer showmanship.
The avian world has all manner of visual and vocal displays
to attract attention and impress.
Lyrebirds shake their tail feathers
like a Las Vegas showgirl.
Mannikins moonwalk like Michael Jackson.
Prairie chickens use big boom base that can be heard
over a kilometer away.
Brolga cranes jump, dance and pirouette
like prima ballerinas.
And Magellanic penguins bill tap and flipper pat
like Bavarian slap dancers.
The sooty tern is another avian groover.
Noisy and gregarious at breeding sites,
they form large communities on rocky islands.
The incessant calls of the colony have given
the bird its name; wide awake.
Unlike most terns, they don't dive,
but pluck fish from surface waters.
At the onset of the breeding season,
sooty terns congregate in dense arial swirls off shore
gradually getting closer to the nesting ground.
Courting pairs engage in high flights.
They ascend to great heights,
then glide rapidly down to sea level.
Once the terns settle on the ground, they begin to display.
With thousands of pairs in close proximity,
the honeymoon couple need to stand out from the crowd
to get to know their new partner and form a bond.
Prior to mating, both mates circle around each other
with dropped wings and heads tilted.
Sooty terns are monogamous,
and this visual display serves to form a strong relationship
necessary to rear young over the coming weeks.
Once the pair is formed and eggs are laid,
both parents take turns incubating the eggs in shifts.
When the chick hatches, forging duties are also shared
and sound sense plays a part.
Adults call from the air as they come back
to feed their chicks.
The chick recognizes its parents' voices and calls back.
They continue calling until the chick walks out to meet them
and the family share a fish supper.
The satin bowerbird is not particularly flashy
in the looks department.
But it does have a unique way of getting attention.
What it lacks in colorful plumage
it makes up for by kleptomania,
stealing objects that it considers to be beautiful
and worthy of display.
This bird weaves a bower with thin twigs
in an area to present its treasure for public viewing.
The bowerbird is hoping to catch the eye
of a passing female.
It's particularly fond of blue objects.
Different species have different color preferences,
and researchers are trying to find out why.
One theory is that bowerbirds choose
the pigment that best complements their own coloring.
The hardworking house husband spends a great deal
of time arranging and rearranging his collection.
He's meticulous at maintaining his design.
When a big bird, like a brush turkey, comes wandering in,
trampling his interior decorating,
the poor male has to start again.
But finally, it seems a female has taken interest.
She inspects the bower and its contents.
The bower and the blue treasure are only
an enticement to step into the male's bachelor pad.
The next stage of the courtship is the dance.
The male leaps into action with a ritualized display
of strutting and quivering, all the while
carrying one of the bower decorations in his bill.
To add to the assault on the female's visual senses,
the male accompanies his routine
with a variety of mechanical sounding calls.
If impressed, the female stays in the love shack for mating,
then she will leave to begin nesting duties on her own
while the male readies himself for courting new girlfriends.
Communicating accurate information is important
if you want to get the girl, but there are animals that send
out messages which are far from the truth.
Some predators deceive their prey to make capture easier.
The alligator snapping turtle sits on the bottom
of a pond waiting.
He eats gambusia fish, which feed on mosquito larvae.
Weighing up to 90 kilos, this reptile is one
of the largest freshwater turtles in the world.
The secretive sluggish creature spends most
of the daylight hours hiding.
Moving fast isn't in his repertoire.
The turtle doesn't seem capable
of catching swift moving fish like the gambusia,
but it has a cunning strategy.
It lies in wait with jaws wide open.
On the bottom of the mouth is a worm-like lure
which it wriggles to entice on where he prey.
The powerful sharp edged jaws are capable of severing
a finger, and the fish stands little chance of escaping.
This is predator to prey communication
and visual trickery is the name of the game.
But the title of master trickster should go
to this creature.
Dangerous and cunning, the portia spider
is a master of deception.
Portias are a genus of jumping spider.
Its favorite food is other arachnids,
like this one, a green water spider called a hygropoda,
which produces mat-like webs on leaf surfaces.
The nonsticky silk doesn't snag prey as such,
the web serves more as an arena
for the fast acting hunter to capture its dinner.
The slightest movement is a critical attack queue.
With stabbing fangs, hygropoda is a lethal adversary
for a predator, but the jumping spider is not deterred.
Using a remarkable hunting tactic,
it exploits the water spider's sensitive detectors.
The hunter slowly approaches the web of its prey.
Moving its legs along the web, the portia plucks
the silken strands as it goes.
It's not just testing for movement, but delicately
strumming the threads to arouse the web owner's curiosity.
With stealth as a weapon, the jumping spider
is mimicking its victim's prey.
This unique cryptic stalking is a remarkable strategy,
but that's not all.
Portia spiders are astounding scientists
with their range of hunting behaviors.
Their strategies alter depending on
the species of prey in question.
These red backed spiderlings are defenseless
against the portia's cunning.
They can improvise their tactics in unfamiliar situations
and remember the technique.
Researchers don't understand how a creature
with such a small brain can seem so intelligent.
But what is plain to see is the portia spider
uses the sense of touch to deceive its prey.
(light music)
The senses are the stars on "Animal Super Senses".
In this show we found they are vital
to animal communication.
Visual displays depend on sight,
vocal performances rely on hearing,
and scent trails trust in the sense of smell
to deliver a message.
Without senses, animals couldn't communicate.
They would be isolated and struggle to survive.
Senses truly are sensational, as we've seen.
Find out more amazing powers of animal perception
next time on "Animal Super Senses".
(light dramatic music)