Imagine a world composed solely of a single, endless desert.
What extreme forms of life might we find here?
Would this be a world of microscopic organisms… or of unfathomable giants?
Arrakis, also called ‘Dune’ is the titular planet at the center of the world-famous science
fiction book and recent film of the same name.
And although the planet is a desert of intense heat and extreme scarcity, it is also abundant
with unexpected life.
So, join me in this tour of the ecosystems of Arrakis, which will dive deep into the
extended material from the books and other sources.
We’ll uncover how such fantastical forms of life might function, and find biological
analogues in the most unexpected places on our own planet.
So, let’s begin our expedition across Arrakis.
Be sure to walk without rhythm…
Few places in the universe compare to Arrakis.
In terms of precipitation, the planet is as dry as the surface of Mars.
Compared to such a world, Earth is a land practically overflowing with water.
Desert animals on Earth have evolved countless strategies to survive the intense heat and
sand, but many of these adaptations will be of little use on Arrakis.
Yet according to the novel, virtually all species on the planet of Arrakis were introduced
from elsewhere, so some familiar creatures must be able to endure this climate.
As we set off to find some… stay close.
For the Desert takes the weak.
Hopping across the sands, is a very special form of hopping desert rodent.
Known as Muad’Dib by the Freh-men populace, the jumping rodent is an introduced species
from Earth called a Jerboa.
A creature that lives in the hottest regions of North Africa and Asia, Jerboas are excellent
fits for the brutal deserts of Arrakis — where they have evolved an unexpected new behavior…
The Villeneuve film shows the Muad’Dib collecting dew gathered on its ears for moisture.
This behavior is highly convergent with the survival strategy of one of the most extreme
desert lifeforms on Earth: the Namib Desert Darkling Beetles.
On foggy desert days, these beetles collect water droplets on their body’s surface thanks
to specialized hydrophilic bumps on their forewings.
This incredible behavior, known as ‘fog-basking,’ requires the beetles to stay motionless for
long periods in this posture — which allows for the collected water to trickle down into
their mouths.
Looking at these species’ hydrophilic zones under magnification reveals just how advanced
their miniature moisture-farms have become.
Truly, life can adapt to almost any environment…
So, it is likely the ears of the Arrakeen Muad’Dib rodent possess similar hydrophilic
zones to facilitate the collection of water from the atmosphere.
In this extremely arid environment, very few species of introduced plants have been able
to take root.
Certain genuses of cacti are some of the only florae that can endure the scorching Arakeen
sun.
And aside from the Muad’Dib, only a small number of Earth animals have managed to sustain
an existence in this land of scarcity.
According to the book, a genus of desert hawks has successfully survived as mid-sized predators,
and an unspecified genus of desert foxes has also made their home here, filling a similar
niche.
But these predators are comically low on the food-chain, compared to the largest and most
famous lifeform on Arrakis.
No species holds more power or commands more awe than the mighty Sandworm — a creature
of endless biological mysteries.
The common name of these colossi calls back to the tiny worms of earth, although the two
share no genetic relation.
While Sandworms and earthworms are both lifeforms with tube-shaped body-plans that burrow underground
in search of organic matter — the main difference comes, of course, in size.
Earthworms average a few inches or centimeters long, whereas sandworms can reach 1,400 feet,
or 450 meters in length…
In sheer volume, the closest thing we have on earth to a sandworm are the largest species
of whales.
And in the Villeneuve film especially, sandworms seem to have a lot in common with whales,
with their teeth almost looking like baleen.
This makes a lot of sense, as in whales baleen bristles are highly effective at filtering
the vast schools of tiny organisms that whales feed on to reach their ridiculous sizes.
And we know from the Dune books that Sandworms have a very similar food source, which helps
make their absurd sizes a bit more realistic…
We’ll discuss the surprising food source of the Sandworms soon.
For now, there’s another great mystery of the Sandworms we need to solve.
How could a creature ‘swim’ through the sand?
Sand as we know it is made up of granular material, not exactly good for swimming through.
Well, it’s possible the sandworms are able to make the sand of Arrakis behave more like
water through a process called fluidization.
The concept of fluidizing a granular material like sand might sound like science fiction,
but scientists have long been able to achieve this by introducing gas, which surprisingly
makes sand behave like a liquid.
And it’s not just scientists who have figured this out.
When earthly sand-swimming animals like the wedge-snouted skink burrow, their movements
create more fluid-like sand that is easier to move through.
Director Villeneuve implies that sandworms swim through the dunes of Arrakis via a similar
process by having the sand subtly liquify before they surface.
Notably, Sandworms can also sense rhythmic vibrations and irregular shifts on the surface
of the sand, and aggressively pursue the origin of such vibrations to defend their territory.
Once again, there are numerous surprising examples in nature of animals that can sense
vibration to track other lifeforms, including snakes — and, perhaps more surprisingly,
frogs.
But the most intriguing example for our purposes are spiders, which can detect tremors caused
by panicking prey caught in their web.
Spiders can detect these subtle vibrations thanks to mechanoreceptory organs on their
exoskeletons called Slit Sensilla.
It’s possible that Sandworms possess their own mechanoreceptory organs that allow them
to ‘hear’ vibrations on the surface.
And when a Sandworm surfaces, it’s quite the spectacle.
As a result of static electricity being released into positively charged air, dry lightning
illuminates the Arrakeen sky.
Seeing a sandworm breaching would likely be like witnessing the approach of a deity.
And some Sandworms might be even more impressive.
There are rumors in the novel of worms that grow up to 2,000 to 3,000 feet, or 700 to
1000 meters, in the southern polar regions, although this could not be confirmed.
If such creatures are hiding on Arrakis, they’d be the largest creatures I’ve ever covered
on this channel… bigger than two Empire State Buildings—put together.
So what are these creatures’ food source?
To find the abundant life that feeds the great Sandworm, one must look under a microscope.
The lower sands of Arrakis are filled with planktonic life, which the Sandworm feeds
on.
But what’s most bizarre is that these tiny organisms — called Sandplankton — are
actually the larval stage of the Sandworms!
That’s right, the sandworm feeds on members of their own species, and are both the foundation
and top predators of the Arakeen ecosystem.
But is such a bizarre, cyclical food-chain even possible?
Once again, a possible answer lies in nature…
Studies of North American Tiger Salamanders have uncovered a highly bizarre and somewhat
similar life-cycle.
Most Tiger Salamander Larva are small creatures with round, almost nonexistent teeth which
proliferate in large numbers.
On rare occasions, however, some larva morph into larger organisms, with wider mouths and
enlarged teeth — and honestly, they look a bit like Sandworms from certain angles.
And like the Sandworms, these predators feed primarily on the smaller larvae of their own
kind.
And there is one other stage of the Sandworms lifecycle: the blob-like, intermediary form
of the Sandtrout — or the ‘little makers.’
Although these slow, amoebic forms might not seem significant, their biological processes
naturally create one of the most important substances in the Dune universe: the Spice
Melange.
In the Dune universe, the spice is one of the most valuable substances due to its effect
on the human mind — unlocking the key to interstellar navigation and having so much
sway it can topple empires.
So, it might sound unusual that it comes from a routine process of an organism like a Sandtrout.
Yet numerous earth animals — from frogs to sea slugs — naturally produce concentrations
of unique chemicals with valuable medicinal and scientific applications.
Granted, the sci-fi powers of the Spice are far more extreme…
But Arrakis is a planet of extremes.
It is a world where the very smallest and very largest lifeforms play a role in the
destiny of all who venture into the desert.
And although we’re at the end of our investigation of this perilous and mysterious world, remember
the great desert can never be understood in its entirety...
As always, thanks for watching.
If you enjoyed this entry, please help make this work possible by liking, subscribing,
and hitting the notification icon to stay up to date on all things Curious.
See you in the next video.