The vast oceans of the popular video game
Subnautica teem with alien creatures — some friendly — and some deadly. While the game focuses on survival, the lifeforms
of Subnautica are amazing even when they’re trying to eat you: possessing fascinating
biology, bizarre behavioral patterns, and hidden mysteries. So, for this entry into the archive, we’ll
embark on a documentary-style expedition, touring ecosystems from the shallows to the
abyssal trenches; swimming in the shadows of giants, and evading predators of the deep. This series will reveal the biology behind
these puzzling lifeforms, and investigate how they differ from life in our own oceans. And although it’s been a while since this
Archivist has done any fieldwork, I’ll be diving into the perilous seas of planet 4546B
myself to capture footage of these magnificent lifeforms. So, let’s take the plunge together, and
see what awaits us under the surface… Beginning in the safety of shallow warm waters,
we find that stable conditions have led to a region crowded with varied life. Here, you can encounter all manner of undersea
organisms. One of the first lifeforms we can spot are
the Peepers… or rather, they spot us, with their enormous, dinner-plate like eyes. These easily identifiable creatures have evolved
visual sensors capable of discerning colors not just in clear waters but in a variety
of lighting conditions. This, combined with their surprising speed,
means that despite being herbivores, Peepers aren’t at the bottom of the food chain. That distinction instead belongs to these
creatures, the rather unfortunate looking Garryfish. Docile herbivores that are remarkably slow,
the Garryfish make easy prey for most anything else in these shallow waters. All ecosystems, including the oceans of earth,
need something near the bottom of the food chain, after all. Other common herbivores on 4546B include the
Bladderfish, which swims by contracting and expanding its translucent bladder, and the
unusual Boomerang, a horizontally symmetrical oddity that possesses a mouth full of sharp
teeth to break down coral. On the subject of coral, the landscape of
the Safe Shallows is dominated by one particularly unusual lifeform. These gargantuan tubes are large enough to
swim through, and despite appearances, are very much alive. Aptly called Giant Coral Tubes, they don’t
look much like the coral we know on earth. These tubes have evolved to filter nutrients
that flow through their center, and judging by their size and abundance, it’s a strategy
that has been quite successful. Gliding near the tubes is the elegant Rabbit
Ray — the first of many ray species we may encounter. The undulating motion that the Rabbit Ray
uses to swim through the clear seas is analogous to the underwater movements of various types
of earth rays. But it’s not the movement of the Rabbit
Ray that gives it its curious name. Instead, the Rabbit Ray’s most defining
features are its twin orange appendages that help it sense vibrations. These ear-like structures resemble the ears
of rabbits, and so the aquatic Rabbit Ray shares a name with an otherwise dissimilar
terrestrial herbivore. Beneath the shallows twist a network of underwater
caves. While exploring one as I gathered this footage,
I heard a strange noise… And a fish exploded in my face. That short-lived creature was a Crashfish
— an evolutionary oddity that is difficult to study due to its highly frustrating habit
of exploding when anything gets close. The Crashfish is defending the sulfur plant,
that provides the Crashfish its home. While an animal exploding to defend its territory
might seem too outlandish to evolve, there’s a model of such behavior on our own planet. Though uncommon, certain species of ants have
been observed erupting into goo to block tunnels when their nest is under threat. Truly, nature is highly unusual — no matter
the planet. Elsewhere in the caves, the far less bothersome
Shuttlebugs drift near the stone walls. Shuttlebugs are challenging creatures to make
sense of: with three legs and three mandibles that have evolved into fin-like tentacles. Despite looking slightly unsettling, analysis
suggests Shuttlebugs are too small to be a threat to most organisms, and have instead
adapted to feed on the waste products of the ecosystem around them. Leaving the caves, you’ll see our first
large species is waiting for us: the Gasopods. These rotund, leathery beasts resemble Earth
manatees, yet have a curious defense that is all their own. Although not in any way hostile, when threatened,
the Gasopods will nonetheless release a deadly cloud of underwater mist… which I can’t
recommend ingesting. Chemical analysis of the Gasopods tells us
the poisonous compound comes from the bulbous appendage at the end of their tail. Since Gasopods are social creatures, it’s
possible they even use these clouds to communicate with one another. But while the Gasopods are the largest creatures
in the Safe Shallows, they are barely the tip of the proverbial iceberg when it comes
to planet 4546B. Venturing into the vast Kelp Forest, we’ll
find a radically different environment than the region we just left. Here, the light is low thanks to the high
volume of creepvine plants — creating a hidden ecosystem, just like kelp-heavy regions
in Earth’s oceans. Here and there, clusters of Creepvine Seeds
cast shadows across the environment like natural floodlights. I find myself wondering just what might be
hidden among the swaying fronds… That is a Stalker: the largest predator that
makes its home in the dense Creepvines. These fearsome customers possess a series
of dorsal ridges to help them make tight turns. Their long, thin snout is likely adapted for
ensnaring fish, as it greatly resembles the effective, slender snout of real-life gharials. Yet at the edge of the Kelp Forest, one Stalker
is behaving… rather oddly. This Stalker is picking up various pieces
of metal scrap with its snout, only to drop them after a short period. This behavior seems to serve no practical
purpose, and indeed the stalkers seem to simply have a fondness for shiny objects. Puzzling as this behavior might seem, the
barracuda — a predatory earth fish — is also known to be attracted to shiny objects
because it’s evolved to spot the silvery glint of the fish it prefers to prey on. And when one considers the common prey of
the Stalker, this attraction to shiny materials makes perfect sense. In the murky depths of the Kelp Forest, schools
of fast-moving hoopfish light up the dark with their vibrant coloring. A brief study of hoopfish anatomy reveals
they get their name from their antennae, which extends from the top and bottom of their heads
and bends around their tails — forming a hoop. Exactly why these stunning fish possess such
intense and varied colors, however, is a mystery. On the subject of mysteries, the last fish
of the Kelp Forest we’ll see is quite the enigma. Meet the Hoverfish: a peaceful herbivore that
appears to ‘hover’ on the pads at the ends of its six legs. Using these strange appendages, the Hoverfish
glides on the undersea currents in a manner quite dissimilar to any other fish on the
planet. It’s surprising to learn, therefore, that
the hoverfish may actually be a distant relative of the nondescript bladder-fish, with their
‘legs’ a highly derived form of the bladderfish’s primitive vacuole tubing. It’s the kind of creature that could only
exist in the Kelp Forest. Just beyond the waving Creepvines, the landscape
gives way to an alien Grassy Plateau. Here, the sandy terrain is almost completely
carpeted with Blood Grass, as the seafloor is too deep for Creepvines to take hold. And in the open space, even larger lifeforms
are on the prowl… At the edge of the Grassy Plateau, a strange
cloud of sand is gathering. Be cautious—as we swim closer to the unexpected
turbulence, a creature with a huge, fanged mouth lashes out. This is a Sand Shark, a predator with a distinctive
hunting strategy. The Sand Shark burrows into the sand, then
erupts out when unsuspecting prey swims by: ending the chase with a snap from its massive
jaws. With segmented body armor and six rows of
fearsome teeth, it’s little wonder why these predators are so effective. Alien as this behavior may seem, some sharks
on earth employ a similar strategy in swimming along the sandy floor near the shoreline in
search of food, although they don’t possess the extreme tunneling abilities of the Sand
Shark. A common target of the Sand Shark’s brutal
ambushes swims overhead. The Spadefish doesn’t look like much from
most angles, but glimpse one from above and you’ll spot its defining feature: a single,
cyclopean eye. Closer analysis of the Spadefish suggests
it feeds on the sea floor, and its single eye allows the spadefish to spot predators
above it. Its mottled green coloration suggests it normally
hides among sea grasses like many fish do on earth. When a Spadefish wanders onto the Grassy Plateaus,
however, it is hopelessly exposed… On the far side of the Grassy Plateau, what
appear to be tiny floating islands hang miraculously in the water. Upon closer inspection, these chunks of rock
are all suspended by colonies of the same, curious lifeform: the Floaters. Transparent, gelatinous blobs, floaters are
at once oddly beautiful, and a little silly looking. Analysis of these creatures reveal they’re
actually multiple microorganisms living in symbiosis, which we can compare to some deep-sea
species of jellyfish. The floater’s ability to suspend such heavy
objects, however, remains something of a mystery. Swimming close by the floating islands is
a distant relative of the peeper called the Reginald. The entire back end of these oddly-named fellows
is composed of one large fin, and the fin’s bright coloration appears to be part of a
mating ritual. Biologists believe the Reginald filters algae
and other plant material from the water via four gill-like, forward-facing orifices. While this is a noteworthy adaptation, something
looming behind the Reginald demands our attention. In the abyss beyond the edge of the plateau,
the largest organism we’ve yet to glimpse calls out through the deep. This is a Reefback: a leviathan-class organism
that exceeds lengths of 220 feet or 70 meters, and is, thankfully, quite friendly. Swimming closer to these gentle giants, we
can see they’re unlike any lifeform we’ve yet to glimpse. Possessing a thick exoskeleton, their shells
have become an oasis of life. Adult Reefbacks can support mini-ecosystems
on their back: including many types of coral and small fish. And nearby this adult is its baby: a much
smaller creature whose shell is not yet ready to support an ecosystem like its parent’s. I confess I spent some time just watching
these creatures drift in their pods, listening to them call out to each other with complex
sounds that suggest a surprising amount of intelligence. With
the sun now getting low, it’s time to venture deeper into the abyss, and enter the foreboding
final biome of the Dunes. In this fast, empty expanse, life often flocks
near hydrothermal vents. These great fissures on the sea floor release
a rich chemical soup into the water, much like those that support life in the depths
of Earth’s oceans. But it’s not life among the vents that concerns
me… A terrifying roar comes from above. A Reaper Leviathan strikes out in the abyss. This aggressive apex predator possesses four
mandibles at the front of its maw to drag in large prey. And at 180 feet, or 55 meters in length, a
hungry Reaper Leviathan can take down almost anything. Analysis of the organism’s biology suggests
the deep roar emitted by the Reaper is a form of sonar – meaning if you can hear it, the
reaper can see you. Thankfully, it seems this Reaper isn’t hungry. And as I watch the deadly leviathan vanish
into the darkness, I realize I’ve done enough field work for the day… The sun has now set on 4546B. Yet the wonders of this planet continue, as
in the low light, various regions of the sea are transformed by stunning displays of bioluminescence. Even the Reefback pod from earlier is now
giving off a striking glow. This eerie beauty suggests the many hidden
wonders we have yet to see beneath the surface. We’ll venture farther into the depths in
Part Two of the Biology of Subnautica, investigating the larger, more extreme, and often more dangerous
life of the deeper biomes. For now, though, our journey is at its end. As always, thanks for watching. If you enjoyed this entry, please lend your
support to help makes these videos possible by liking, subscribing, and hitting the notification
icon to stay up to date on all things Curious. See you in the next video.
That’s really cool! Nice job!
I watched that and really enjoyed it good job