Human beings have existed for 300,000 years
and have managed to live
in many unstable environments.
We've survived ice ages,
devastating pandemics
and World Wars.
But how would we fare even further back in time?
What about 400 million years ago,
when deadly marine life dominated our oceans
and creatures on land
were practically non-existent.
Let's imagine your What If time machine
happened to break down right at this moment,
trapping you in the Devonian Period.
This is What If and here's what would happen
Stroke of luck, our time machine stops you on land.
At this point in time,
85% of the Earth was comprised of ocean.
Only two supercontinents existed
600 million years ago,
Gondwana had a massive mountain range
similar to the Himalayas,
which slowly eroded,
washing sediments into the ocean.
These sediments provided nutrients
that allowed marine life to flourish,
giving rise to the Devonian Period.
Okay, enough background.
Our first step for survival is to seek shelter.
In the early Devonian Period,
trees and plants had not yet evolved.
But there was lots of moss!
The land was barren,
Mars-like and surrounded by water.
You might need to get a little creative
to build shelter.
If humans actually evolved in this period,
they would likely be naked
with little material to make clothes.
Or maybe we would develop a new fashion line
made of moss, seashells and fish bones!
Ooh la la, how Devonian chic!
Speaking of fish bones,
you'd want to be very careful about fishing.
Many scary sea creatures
would be happy to eat you.
Like Placoderms, a species of armored fish
with huge sharp jaws
that could easily make you bite-sized.
In the early Devonian Period,
Placoderms were the apex predator
and would grow up to 10 meters (33 feet).
Let's say you got lucky and actually caught a fish,
without being eaten yourself in the process.
How would you cook it?
With no trees for fuel,
you'd have to find some very dry moss
and start rubbing some rocks together.
Luckily, the climate was pretty warm,
meaning you wouldn't freeze at night.
But with very little kindling available,
you might be better off sticking to
a raw diet of mollusks and other early arthropods.
You'd also have to move around
a lot to keep finding these critters,
so be prepared to do a lot of walking.
Hmmm, I can see you're getting a little tired
and bored existing out there.
Let's fast forward another 40 million years
toward the Late Devonian Period.
This period is also known as
But don't worry!
It could actually be a really good time for you,
fearless traveller.
Since by this point,
almost 79% to 87% of all existing species were wiped out.
What could cause such a catastrophe?
Scientists believe it was the evolution of plants.
Vascular plants began dominating the environment,
including trees, ferns and flowering plants.
Their roots broke up the rocky ground
and released nutrients and minerals in the water.
These nutrients fed algae,
which multiplied rapidly and produced
greedy bacteria that fed on oxygen.
Many regions of the ocean became
and much of the marine life died off
due to the lack of oxygen
With more air in the atmosphere,
some sea creatures slowly adapted
and made their way to shore.
So, you can breathe easier
knowing there are less predators in the water,
but look out for your new neighbors on land!
These land dwellers, known as
were the early ancestors of amphibians
and all four-legged land vertebrates.
In fact, the Devonian Period got its name
from the fossils of lobefins
found in Devon, England.
In 2004, a lobefin fossil
was found in the Canadian Arctic
known as
which is considered to be the species
between fish and land-dwelling tetrapod.
It had a crocodile-like head,
bony fins,
sharp teeth and a flat body
almost 3 meters (9 feet) long.
Its fins had partial wrists
allowing it to crawl on land.
So, if I were you, I would quickly hide
if I saw a Tiktaalik coming my way.
The other dominant species were Cartilaginous fish
with skeletons covered in,
you guessed it, cartilage.
These are the ancestors of sharks and rays.
But you don't have to worry about sharks.
Oh no, there's something far bigger, and scarier!
I'd keep my distance
if you happen to see a
swimming around!
These were the deadliest predators
of the Devonian age,
with thick, bony plates
covering their skulls and razor sharp jaws.
Some would grow up to 10 meters (32 feet) in length.
Their jaws were strong enough
to chomp right through another Dunkleosteus.
With few fish left
because of plants hogging the oxygen,
these placoderms were starving
and desperate enough to eat each other.
So, be very careful where you bathe!
With more trees and plants
emerging in your environment,
you could finally create some helpful tools,
like spears, fishing hooks, and rope!
You could improve your diet
and maybe become a vegetarian!
And you could fashion some new clothes
that aren't so irritatingly itchy.
By the late Devonian Period,
you might even be able to build yourself
a treehouse in the
the first tree on Earth
which grew up to 30 meters (90 feet) tall
with a trunk 3 meters (9 feet) wide.
This may be nice for a while,
but if you think the Devonian Period is easy,
you might want to plan a hasty exit
before the Cretaceous Period rolls around.
Who knows, maybe ancient life
found a way to escape our planet?
That sounds like a story for another What If!