(upbeat music)
Any one fascinated by the natural world
has probably wondered why some animals
have such strange looking sense organs.
The elephant with its huge ears,
(elephant trumpets)
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.
(intense drum beats)
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.
(bee buzzes)
Animal super senses.
You won't believe what's possible.
(suspenseful music)
Animal is that live life on the wing
have a vast expanse of sky to navigate,
find mates, locate food, and avoid predators in.
Living in this aerial realm requires a unique set
of senses, specialized to cope with life above ground.
In this episode of Super Senses,
we find out more about when senses take flight,
and animals become masters of the sky.
The speed and precision of a bird of prey
captures our attention and leaves us awestruck.
From a soaring height,
they scan the ground for a pigeon sized meal.
Open grassland is perfect territory.
To cope with searching a vast area,
they need super sharp sight.
(intense music)
The peregrine falcon, like most predators,
has forward facing eyes.
Binocular vision helps in depth perception,
essential to spot fast moving food.
Their eyes rely on several visual enhancements.
Each eye has two fovea, dense areas of photo receptors.
Most animals only have one,
but the peregrine falcon has a deep and shallow fovea.
These clusters of light sensitive nerve cells
provide acute vision for viewing distant objects.
(intense music)
Their favorite prey are medium-sized birds.
They mark their target from a height of 1,500 meters.
(intense music)
With a power stoop reaching speeds
of over 300 kilometers per hour,
such acceleration would cause eyes to dry
out as wind evaporates the tear film,
but a nictitating membrane, or third eyelid,
clears the eye of debris,
and a specialized gland at the base of the membrane
secretes a solution that moistens the cornea,
and protects the eye during the breathtaking stoop.
(intense music)
As an ariel sniper,
the peregrine falcon is a sight to behold.
When a meal is spotted the predator stoops,
with wings folded close to the body.
It's the perfect shape for dive bombing.
(intense music)
It strikes the pigeon with his talons,
stunning it on impact.
Then turns to catch it in midair.
(bird screeches)
If the prey is too heavy,
the peregrine will drop to the ground
where it settles to pluck the feathers before feeding.
(soft percussive music)
With such formidable vision,
the falcon's prey stands little chance of escape.
The falcon's sharp vision is impressive,
but there is another bird of prey that can beat it.
The wedge tail eagle also has two fovea in each eye,
but it has the advantage of size.
(upbeat music)
It's Australia's largest bird of prey.
The wedgey, as it's known, has the keenest vision
of any animal and their eyes,
relative to body size, are huge.
(birds caw)
(upbeat music)
A 4.5 kilogram eagle may have eyes
as big as a 90 kilogram human.
(upbeat music)
Sporting a two meter long wingspan,
this raptor truly is lord of the skies.
(upbeat music)
It takes flight with slow, deep wing beats.
And once aloft, skillfully uses updrafts
of thermals to reach heights of 2000 meters.
(upbeat music)
Such powerful wings are put to good use
as it hunts by soaring above the open country,
looking for rabbits and wallabies.
(upbeat music)
Once spotted, it dives down at speeds
of more than 80 kilometers per hour,
grabbing its unsuspecting prey
with his formidable seven centimeter long talons.
(upbeat music)
(bird screeches)
Big, beautiful, and predatory,
birds of prey get our attention,
yet they share the sky with a much smaller
winged hunter that could teach the raptors
a lesson or two.
Dragonflies, ancient aerial killers
that seem dainty and ethereal,
but don't be fooled by their delicate looks.
(peaceful music)
New research suggests
that the dragonfly may well be the most brutal
and effective predators in the animal kingdom.
With military precision and fighter pilot control,
they rarely miss their insect prey,
managing to snatch their targets in midair
more than 95% of the time.
They don't even stop to finish one meal,
stuffing their mouths full of meat,
while moving on to catch the next victim.
(peaceful music)
They can fly backwards,
change direction in midair,
and hover for up to one minute.
What makes the dragonfly such an effective hunter?
Dragonflies have multifaceted, or compound, eyes.
And, along with bees, have the largest eyes of any insect.
(peaceful music)
The dragonfly sees the world in a mosaic.
They have more light-sensitive proteins called opsins,
and this allows them to see colors that are
beyond human visual capabilities,
such as ultraviolet light.
(peaceful music)
But that's not all.
The light sensitive proteins are segregated
in the compound eye with the upward facing part
only having blue and UV receptors.
(distant frog croaking)
It's thought it gives a special advantage
to hunting dragonflies.
As the sky appears to be very bright,
providing a clear background
against which their small moving prey
can be more easily detected.
Another advantage of having a multi-faceted eye,
is the dragonfly's acute sensitivity to movement.
(peaceful music)
Their super sense eyes make the dragonfly
the stone cold serial killer of the skies.
Each autumn, millions of Monarch butterflies
fly about 3000 kilometers
from the Eastern United States
to Central and Southern Mexico to spend the winter.
(soft music)
(bird calls)
The monarch's migration is one
of the most spectacular sights in nature.
(soft music)
(bird calls)
Past research has shown the winged travelers
navigate using the sun, but the question remained
how do they manage to stay on course during cloudy days?
(soft music)
The answer lay once again,
in the ultraviolet realm of the sky.
(soft music)
This time, the UV light wasn't providing the direction,
but acted as a switch to trigger a magnetic compass
located in the butterfly's antennae.
(soft music)
Researchers have found that light-sensitive molecules
in the antennae are turned on by ultraviolet light,
the wavelength that peaks during summer.
Because UV light can penetrate clouds
and reach the butterfly's receptors,
even on overcast days, their inbuilt GPS can kick in.
(peaceful music)
This magnetic compass may serve
as a backup navigation system
to keep the butterflies on track
when they can't see the sun.
(peaceful music)
So we have super senses,
like ultraviolet and polarized light,
that help airborne animals find food
and navigate their way.
They are all about what can be seen
of the wide blue sky that animals can use.
But what about the other senses?
The sense of smell responds to airborne chemicals
but in the expanse of sky,
are the molecule is too dispersed?
Modern birds are known more
for their flying abilities
and their sense of vision and balance
than for their sense of smell.
But some bird species still rely on smell
to search for food or navigate over large areas.
And recent research suggests
that they may have inherited this from the dinosaurs.
New world vultures, like the black vulture,
live in the warm and temperate areas of the Americas.
(upbeat music)
It is a typical scavenger,
feeding on dead and decaying flesh.
(upbeat music)
And it soars high above the ground,
looking for its next meal.
(upbeat music)
But, it doesn't have a particularly sensitive nose.
Instead, this clever bird keeps a keen eye
on the activities of its new world cousin,
the turkey vulture.
(upbeat music)
Turkey vultures can be seen circling
effortlessly high in the sky.
They are easily recognized by their red featherless heads.
(upbeat music)
But the Turkey vulture's real claim to fame is
as one of the few birds in the world
that have a super sense of smell.
(upbeat music)
Experts estimate that they can detect the scent
of rotting flesh in concentrations as tiny
as a few parts per billion in the air,
and are able to sniff out a dead critter
more than a mile away.
(upbeat music)
While gliding in the sky,
they track plumes of foul, sulfurous odors
from decaying animals
and home in on it by flying in circles.
(upbeat music)
Watching closely is the black vulture.
Lacking in the sense of smell department,
but smart enough to watch the turkey vultures
find the food and then follow when the time is right.
(upbeat music)
(bird calls)
Birds and insects are renowned for their aerial ability,
but mammals have only one representative
capable of powered flight, and that's the bat.
(urgent music)
Like other animals, their senses are adapted
to deal with life above ground.
The saying, being blind as a bat,
simply isn't true.
(urgent music)
The bat world is made up of micro bats and mega bats.
Micro bats hunt for insects at night using echolocation,
and yes, their eyes are small.
But the bigger mega bats have larger eyes.
They don't echolocate,
but forage at night for nectar and fruit,
which they find with their acute sense
of sight and smell.
(urgent music)
The forword facing eyes of flying foxes
are adapted for searching for light colored fruit
and flowers at night.
(urgent music)
Flying foxes see well during the day too.
Their daytime roosts are in large open tree tops,
very visible to passing predators.
(urgent music)
Having excellent eyesight means
they can keep a lookout for enemies.
(birds chirp)
The sense of smell also plays an important part
in finding food for fruit bats.
They sniff out the ripest fruit
with the strongest odor,
and cluster figs are a favorite.
(cheerful music)
Flying foxes are very good climbers
Using their wrist and thumb claw to grip,
they crawl across branches to forage.
(cheerful music)
Their teeth are adapted to their diet,
with canines that pierce
and flattened molars to crush the fruit,
but flying foxes don't eat the fruit whole.
The tongue is used to press the pulp
against the hard ridges of the palette
to extract all the juice which is swallowed,
and then the fibrous part is spat out.
The tongue is lined with small projections called papillae,
and covered with taste buds.
Flying fox tongues are so specialized
with different types of papillae and taste buds
reflecting feeding behavior
that each species can be identified
by tongue morphology alone.
(cheerful music)
Smell also plays a role in social interactions.
Secretions from the bat's shoulder glands
are spread over the body while grooming
and smell is used to recognize each other.
(cheerful music)
Males rub their scent onto tree branches
in the colony to mark a territory,
and to attract passing females.
With their acute senses of sight and smell,
fruit bats are able to live a sky high life.
(birds caw)
In the desert of Australia's interior,
thousands of pelicans seem to miraculously appear
at a vast saltwater lake.
(seagulls caw)
It is a wonder of the Australian Outback.
(cheerful music)
Most of the time, the lake is bone dry,
and has little to sustain life.
It's the last place you would think to find a waterbird.
But every decade or so floodwaters
turn it into an inland sea,
teeming with microscopic animals that feed fish.
And the fish eating pelicans follow.
(cheerful music)
(bird squawks)
It's here the lakes support 10,000 pelicans
breeding a new generation.
(cheerful music)
But these nomads of the sky
have traveled across the vast interior
to reach the fish filled waters from the coast.
How do thousands of pelicans know when
to fly hundreds of kilometers to inland waters?
What cues are they detecting?
(cheerful music)
Bird talk, inbuilt magnetic compasses,
and the ability to hear vibrations
from long distances are just three theories
which try to explain why the birds migrate when they do,
but there's no evidence.
(cheerful music)
Experts think the birds may be using riverbeds
as route maps,
but that doesn't explain what triggers the flight.
(cheerful music)
So the mystery of the lake year pelicans
continues to baffle scientists.
(upbeat music)
The senses are the stars of Animal Super Senses.
And this episode has been no exception.
We've discovered animals use a range of senses
to cope with life in the clouds.
Given the distance
and vast openness of the skies,
animals make the most of what the aerial realm has to offer
and human abilities pale in comparison.
So join us next time on Super Senses
to find out more incredible powers of animal perception.
(upbeat music)