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You might have heard of Alaska.
It's known for the Klondike Gold Rush, polar bears,
and an unreasonably elaborate dessert: the baked Alaska.
It’s also geographically distinct from the rest of the United States,
being very far north, with its northern slope peeking into the Arctic circle.
And maybe science isn’t the first thing that pops into your head
when you think about this mostly-frozen region.
But Alaska has a lot to offer when it comes to learning about the world,
from cold corals to our own behavior.
So let’s take a look at research we’ve done by looking at Alaska.
Like, for one, how to grow some truly giant vegetables.
Some of the US’s most impressive veggies come not from sunny California or Florida,
nor the breadbasket that is the Great Plains.
Rather, they’re grown in the Matanuska-Susitna Valley area outside of Anchorage.
And we are talking some real whoppers.
Celery bunches the size of a child, pumpkins that weigh as much as a cow.
The reason seems to be Alaska’s growing season,
the time of the year in which temperature and rainfall allow plants to grow.
As you might expect, Alaska has a short one.
But in that short time, plant growth can be explosive.
During the short, warm summer months,
the plants up there literally make hay while the sun is shining.
And it shines a lot.
Like, almost the entire day, a lot.
The reason for this has to do with the tilt of the Earth.
Because the Earth’s rotational axis is a bit tilted, the northern and southern hemispheres
take turns getting the lion’s share of sunlight as we travel around the Sun.
Near the equator, this doesn’t matter so much because the sun’s hitting you
pretty much straight on throughout the year.
But the closer you get to the poles, the more the axial tilt matters.
The result is very dark winters with very short days.
But the flipside of that is during the summer, days can get pretty long.
On the summer solstice, Anchorage can get more than 19 hours of sunlight
in a single 24-hour day.
And it turns out plants love that.
These super-sunny days give the plants more time to turn the sun’s energy into sugars
and starches through photosynthesis.
This helps fuel their growth, letting them pack on the pounds.
The extra sugars may also contribute to Alaska’s reputation
for having noticeably sweeter produce.
But this leads us to point number two.
As we mentioned, the bright summer days are kind of balanced out
by long, very dark winter months, with the sun only barely shining.
On the winter solstice, the Alaskan city of Anchorage only gets about 5 daylight hours.
And, if you’re north of the Arctic circle, the sun doesn’t come up at all.
But this also presents us with a natural opportunity to study what happens to the people
and animals that live through those dark months.
One particular area of interest is seasonal affective disorder, or SAD.
Seasonal affective disorder is a type of depression
that seems to be tied to the changing of the seasons.
If you have the most common type of it,
you might notice that you start to feel moody and tired in the fall and throughout the winter.
As for why it happens, researchers think it’s tied to the changing light levels
affecting circadian rhythms, hormones, and neurotransmitters.
People who live in areas with more extreme shifts in the amount of light throughout the seasons,
like close to the poles, are at a higher risk of SAD.
This variation gives us an opportunity to understand more about how SAD works,
in order to hopefully develop more effective treatment for the people affected by it.
For instance, looking at the prevalence of residents in Alaska with SAD
has given us evidence that SAD happens more often in women than in men,
and happens less often in people over the age of 40.
We can even zoom in further. A 2021 study looked at SAD in Alaskan gym-goers and found,
perhaps counter-intuitively, that the more social athletes were more likely to experience SAD.
Those who hit the gym and just kind of focused on doing their own thing were less likely.
The authors suggest that it might be because the more independent workout-goers
are following more rigorous exercise regimens.
It’s just one study, but considering that physical exercise is often thought of as being helpful
for depression generally, this could help shape recommendations
for what kinds of exercise might be beneficial for people with SAD.
Now, Alaska’s proximity to the North Pole also makes it fairly chilly, as you might expect.
The poles don’t get as much direct, warm sunlight like areas around the equator do,
so it doesn’t get as warm.
In fact, much of the ground in Alaska remains frozen long-term,
what scientists call permafrost.
In 2021, 85% of Alaska’s land area had permafrost under it.
However, thanks to the climate crisis warming up the Arctic,
much of that permafrost is now melting.
And by looking at what’s happening in Alaska,
we can learn more about what will happen in other Arctic areas, like Russia and Canada.
Like, in Alaska, many homes and buildings are built on permafrost and their foundations
are now turning slushy and unstable.
We can expect to see similar effects elsewhere.
Also, it turns out that melting permafrost is releasing carbon dioxide.
That’s because as the ground thaws, the frozen organic matter like plant leaves and roots
thaws as well, and becomes food for soil bacteria and other microbes.
As this organic matter decays, the bacteria and other microbes release gases
like methane and carbon dioxide. And given that both are greenhouse gases,
this could be the start of a positive feedback loop
as it fuels even more atmospheric warming.
Warmer conditions melt more permafrost which cases
more greenhouse gases to be released, and so on.
And one other really interesting thing that might come out of those root-munching bacteria
in the permafrost is antibiotic resistance.
Now, having antibiotic resistance genes in soil bacteria isn’t unusual,
because it’s actually pretty common for soil bacteria to need to resist antibiotic compounds.
That’s because soil bacteria actually use their own home-made antibiotics
to try to kill or stymie each other.
Just because you live in the same place doesn’t mean you’re friends.
There’s only so many nutrients to go around, after all.
But scientists have looked at the levels of antibiotic resistance in permafrost bacteria
and found that, at least in the area they examined,
as the permafrost melts and is disturbed,
the levels of antibiotic resistance seem to go up.
This seems to be because the community of different species becomes unbalanced by what’s
essentially a huge ecosystem shift as the soil goes from frozen and icy to thawed and muddy.
This frees up more water, nutrients, and even other microbes that’d been previously frozen.
In this case, the bacteria with the antibiotic resistance genes may have some greater
competitive advantage in this new environment compared to their peers,
since they might be able to, say, reproduce faster since they can shrug off attacks.
And this could be a problem for us, as these antibiotic resistance genes can spread out of the
soil and end up out in the wider world, which could make infections in humans more dangerous.
So, by looking at what’s happening in Alaskan soils,
we can better track how melting permafrost is going to affect the world.
Next up is kind of a weird, famous, accidental experiment that Alaska played home to.
St. Matthew Island is an about 350 square kilometer island off the Western coast of Alaska,
kind of in the middle between Russia and Alaska.
It’s never really been inhabited by humans long-term,
but it was home to a navigational facility by the US military for a time.
In 1944, the United States Coast Guard introduced reindeer to the island
as an emergency food supply for troops stationed there.
Reindeer had never lived there before.
There were just 29 of them at first, but with plenty of space and lichen to eat,
the reindeer population exploded.
There were also no significant natural predators; just small mammals and the odd polar bear.
By 1963, there were as many as 6,000 reindeer on the island.
But death was just around the corner, and the next year, their population crashed
to less than 50 animals.
By the 1980’s, all the remaining reindeer were gone.
What happened?
Well, the reindeer overshot what ecologists call the carrying capacity of the island.
They ate their food faster than it could regrow, leading to the entire population
running out of food and starving during an especially harsh winter.
This wasn’t a planned experiment, but it has often been pointed to as an object lesson
in carrying capacity, overpopulation, and what can happen to herbivores
if there aren’t predators around to keep their numbers in check.
Finally, the last lesson Alaska has in store for us today
comes not from an island, but from underwater.
For years, fishing boats that trawled nets along the ocean floor
had occasionally turned up not just crabs and lobsters, but pieces of coral.
And in 2002, scientists discovered that the waters off Alaska’s Aleutian islands were, in fact,
home to not just isolated individuals, but rich gardens full of what’s known as cold water corals.
While tropical corals thrive in warm waters, basking in the sunlight
and using symbiotic microorganisms to produce their own food from the light,
cold water corals often grow in frigid waters, far away from the light.
Some are shallow enough to scuba-dive to, but many grow far beyond that.
The deepest a recreational scuba diver will usually go is about 40 meters,
but these corals can grow hundreds of meters below the surface if not deeper.
They still grow from polyps, the small coral animals whose colonies create coral reefs.
But these varieties don’t need the sunlight.
Instead, they eat what they can catch floating in on the current.
Despite not needing the light, they’re still a sight to behold,
with oranges, reds, and purples, shaped in fans and feather-like forms.
Deepwater corals have been found in a bunch of places around the world,
such as near the United Kingdom, Norway, and New Zealand.
But Alaska in particular may have the highest abundance and diversity of cold water corals
anywhere in the world, with 25 endemic species and subspecies.
The source of the corals’ success is strong underwater currents that wind around
underwater mountains and passes and bring nutrient-rich waters.
That allows the corals to grow in large “groves”,
which provide important habitat for fish and other sea critters.
Figuring out why there’s such high diversity and abundance of cold water corals here
could help us understand how corals grow, disperse, and evolve.
It could also help answer questions about what environmental factors are most important
for coral growth, how important the corals are for fish and other ocean critter species,
and how at risk they are from human fishing fleets.
So that’s Alaska in a nutshell!
Its position so close to the pole has influenced life up there in amazing ways,
from ultra-sunny summers to dark winters and frozen landscapes.
It’s a land of natural experiments and amazing surprises.
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