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Science is at it’s best when it’s raising questions. I mean, yes, technically it’s a method of
searching for answers. But understanding one thing tends to lead
to way more questions than it answers. Which is exciting! We are never going to reach a point
where we know everything about the universe and
just stop doing science. And sometimes the questions
science raises are especially tricky or fascinating, and it might take a
long time to find some answers. So here are 5 mysteries that
science started, and eventually managed to solve,
in some fascinating ways. Evolution is generally a pretty
gradual process where one life form adapts until it’s
changed enough for us to consider it something different. But the fossil record doesn’t preserve everything. Sometimes we have so little evidence documenting
an evolutionary transition that it can be tricky to draw
an unbroken line from ancient animals to those we
see today. One of those mysteries is the European bison,
which seems to have sprung out of nowhere around
12 thousand years ago. And yes, they are still around
in small numbers today. Prior to the European bison,
there are two main bovine groups known in Europe:
ancestors of modern cattle, and ancestors of
North American bison. But the closest relatives of the
European bison remain elusive. So much so that this
ancient creature has been dubbed the “Higgs Bison”,
after the Higgs Boson that physicists spent years
searching for. This mystery persisted until a 2016
study was able to find this ancient creature using
a combination of DNA analysis and cave paintings. Looking at cave paintings of bison, mostly
from France, researchers noticed that many depictions from
around 12 to 17 thousand years ago looked a little
more like European bison than North American. They were drawn
with thinner horns and a smaller hump on their back. So they hypothesized that these paintings
could be depictions of the mysterious ancestors of
European bison. To figure this out, they sequenced DNA from
64 preserved bones and teeth from across Europe, dating
from more than 50,000 to 14,000 years old. The goal was to figure
out if the change in cave paintings correspond to a
change in bison populations. And indeed, some of the
samples from this period were from a previously unknown species. Genetic analysis revealed this ancestor of
European bison was a hybrid between steppe bison, ancestors
of North American bison, and aurochs, ancestors of modern cattle. These hybrids were more abundant during large-scale
climate change between glaciations, suggesting their
population waxed and waned relative to other ancient
species of bison. So even though we don’t have complete
fossils of them, thanks to modern genetics, we can
pinpoint the Higgs bison. And thanks to ancient artists,
we have a sense of what this creature looked like! Scientists are still figuring out the details
of this mystery, and not everyone agrees with this interpretation
of the genetic evidence. So as we gather more clues, we will
get a clearer picture of where the European bison came from. Klerksdorp spheres are bizarre-looking rocks
found in South Africa, often nearly perfectly symmetrical
with uniform grooves around them. They kind of look too perfect to be natural,
which leads to the understandable conclusion that humans
must have manufactured them. But the catch is the rock
around them is more than 3 billion years old, long before
people, or any animals for that matter, roamed the planet. The more outlandish explanations have included
previously unknown ancient civilizations or extraterrestrial
visitors. Some have called them “cosmic cannonballs”. These ideas have come along with bizarre claims
of them being able to spontaneously rotate on their
own and being so perfectly balanced that they could only
form in zero gravity. But geologists have said not so fast. They are very sure
there’s a natural, earth-based explanation. It just took a
while to find that explanation, or at least rediscover it. First of all, there is no evidence to the
claims of spontaneous rotation. Seems pretty unlikely, turns out it is. And if you look at a bunch of them, you see
that while some look like perfect spheres, they actually come
in a wide range of shapes. It’s just that the more round ones that
get the most attention. See, these spheres are a beautiful example
of what geologists call concretions, which slowly crystallize
out of fluids flowing through the surrounding sediments. Crystals tend to grow from a starting point,
called a point of nucleation. This is commonly a little bit of something
different than the surrounding sediment. So once this begins,
the growth of the minerals happens evenly outwards,
forming a sphere or something close to it. It’s the smooth
exterior and bands around the Klerksdorp spheres make
them particularly unnatural looking compared to many
other concretions. Originally the spheres were likely made
of pyrite, but then over time chemical reactions altered
their composition to a variety of minerals, still mostly
quite rich in iron. That just leaves the grooves around
the outside of the spheres to explain. The surrounding rock
is made of layers of sediments and volcanic ash, so the
grooves are likely an imprint of layers from the surrounding rock. Geologists actually proposed pretty much the
same explanation as early as the 1930s, but magazine
articles and TV shows from the 70s to the 90s seem
to have ignored that and perpetuated the mystery. Luckily
geologists were able to clear things up again! So it’s pretty unlikely that aliens are
to blame here. But similar spheres have been seen on other
planets. In 2004, the Mars rover Opportunity found
similar objects dubbed “Martian blueberries”. And they could provide
clues to the history of water on the red planet. But,
of course, since we haven't been able to take a
sample of them directly, we will have to wait a bit
longer for those insights. So, life in Antarctica is tough
no matter who you are or where you are living. But
scientists have discovered that the soils of the
Antarctic deserts are filled with microbes! In fact,
the levels of microbial life are comparable to much
more mild environments. This discovery has come as
a bit of a surprise. And it’s sparked an even bigger
question: how are these communities surviving? See, this soil has very little organic carbon
or other nutrients. And there’s little to no light for much
of the winter, so photosynthesis is tough. On top of all
that, everything is constantly getting frozen and
rethawed, so exactly how these tiny creatures survive
has been quite a mystery. But a 2017 paper found
they might simply be living on air. Trace atmospheric
gases are their main source of energy. The researchers
sequenced DNA from two spots in Antarctica to figure
out what types of microbes were living there. Not
surprisingly, only 0.28% of the microbes were known
photosynthesizers, so clearly the community as a
whole was not relying on sunlight. But using all of
this genetic information, researchers were able to
infer what sort of energy source the microbes were
relying on. They found lots of genes that can take
the carbon from carbon dioxide in the atmosphere, as well as enzymes that assist in using hydrogen
gas and carbon monoxide as energy sources. Carbon monoxide can, of course, be fatal to
humans, so it’s pretty amazing these little microbes
can essentially breathe it. To confirm this is what was
actually going on, the researchers put samples of
the soils inside sealed bottles and measured the
consumption of hydrogen and carbon monoxide. They were even able to tag the carbon in the
carbon dioxide and see it showing up in the microbes
from the soils. That demonstrates that there’s enough carbon
and other nutrients in the air for these microbial
communities to sustain themselves. Now that we
know this happens on Earth, it even opens up the
possibility to look for similar types of life on other planets. Tanystropheus is an extinct reptile that lived
around 240 million years ago. First discovered in 1852, along
the border between Switzerland and Italy, this giant
was 20 feet long and boasted a neck three times as
long as its torso. And it took us more than a century
and a half to work out some of the most basic things
about it. Scientists weren’t sure if it lived on land,
in the water, or even flew through the skies! These kinds
of mysteries aren’t that rare in paleontology. Fossils
are often incomplete skeletons, and frequently smushed
or scattered compared to how they were in life, so it
can be easy to misinterpret what creatures looked like
or how they lived. Over time, as more specimens were
discovered, we realized that bones that were thought
to be part of the creature's wings were actually vertebrae, and this creature had a very long
neck. So flying through the air was ruled out. But it wasn’t
until 2020 that we were able to figure out it lived
underwater and not on land. Researchers used
high-resolution CT scans of fossil fragments to
reconstruct a Tanystropheus skull. This revealed that
their nostrils were similar to crocodiles, and their teeth
were positioned to catch fish. This is similar to the
teeth seen in other prehistoric underwater predators. The researchers made another startling discovery
as well. They were looking at two species, not one. They examined
small and large specimens of Tanystropheus. In the past
these were thought to be juvenile and mature members
of the same species. But markings on the bones of the
small species indicate that their growth had slowed by
the time they died, suggesting they had reached maturity. So it’s most likely these two species coexisted
by hunting different prey, each having its own role in
the aquatic ecosystem. The Explorer’s Club is an organization surrounded
by myth and legend. It’s an exclusive group of scientists and
adventurers, and members have included astronauts, presidents, and billionaires. But one story in particular also
created a tricky scientific mystery that lasted for decades. Though maybe this one is more of a hoax. Rumor has it that
at a dinner in 1951, members of the club dined on wooly
mammoth meat that was preserved in Alaskan ice. This
meal began the club’s tradition of serving exotic meats. Menus since then have included polar bears,
termites and tarantulas, and goat eyeballs. Out of the ordinary
for sure, but nothing like an ice age giant that has been
extinct for thousands of years. Luckily a small sample of
the cooked meat in question was preserved as a souvenir. So in 2015 researchers decided to solve this
mystery once and for all! Their first discovery was the menu claimed
the meat was in fact from something rarer than
a woolly mammoth: an extinct giant ground sloth from
South America called Megatherium. If this were true, the scientific impact
would be enormous, since these sloths have never been
found anywhere near Alaska, and it’s uncertain if humans,
ancient or modern, ever ate them. So the researchers
performed a careful DNA analysis on the preserved sample
and found it was actually neither of these species. It turns
out it was from a green sea turtle. Turtle soup was also
on the menu that evening, so the researchers theorize
one member of the club had the idea to take some of the
meat from that dish and pass it off as something much more exotic. In an article published after the dinner,
one member more or less admitted to doing just that. But the power of a
good story is hard to overcome, and the admission was
pretty much completely ignored. Even though this meal
was an elaborate prank, there are other tales of paleontologists
sampling mammoth meat that the researchers think could
be credible. Apparently, tasting your specimens was once
much more common than it is now! There you go, 5 mysterious
puzzles, both sparked and solved by science! But these stories
aren’t over yet. As methods improve and clever researchers
try new things, we will surely learn lots more about the tiny
creatures in the harshest environments, the giants of the
prehistoric oceans, and which ancient animals taste the best. Well, on second thought, possibly we should
avoid eating the discoveries. All of that science is the result of tons
of data that researchers had to sift through
and organize. And when you have that much data, you need
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