Amber is amazing stuff.
And not just because you can use it to make really cool necklaces
or you know a brontosaurus apparently…
The specimens found in amber can teach us a lot
about evolution or even how diseases like the plagues spread.
That’s because amber preserves organisms whole
and essentially freezes them in time.
How does it happen?
Well, first, some poor plant or animal gets stuck
in a glob of tree resin,
a sticky ,thick substance a plant releases when it’s damaged.
Then, when the resin hardens,
the creature gets pretty much mummified.
The chemical composition of tree resin actually dehydrates organisms,
and that stops the processes that would otherwise break down their tissues.
Resin even has antiseptic and antimicrobial compounds
that help prevent fungi from decomposing things.
This means stuff that normally wouldn’t fossilize well,
like plants and soft animal tissue,
can be preserved in amber.
And the specimens we’ve found in it so far range
from amazing to downright bizarre.
So, without further ado, here are six of the coolest
那么 话不多说 下面是我们发现的
things we’ve found trapped in amber.
First, check out the leaves of this carnivorous plant,
which were described in a 2015 paper
in the Proceedings of the National Academy of Sciences.
They’re 35 million years old,
and they come from a kind of ancient Roridulid plant
a genus of evergreen, insect-trapping shrubs.
Scientists figured this out because the leaves
have features that are really similar
to modern roridula plants found in South Africa.
Like, for one, they’re long, narrow, and tapered.
其中一些特征是 它们又长又窄 呈锥形
They’re also covered in two kinds of hair-like
structures called trichomes.
One kind is stiffer and not sticky,
and the other comes in different lengths and secretes a kind of glue.
Those are the structures that trap and immobilize insects,
which is what makes these plants carnivorous.
Except, roridulids like this ancient specimen also
seem to have a problem:
Once they’ve caught a meal with their sticky trichomes,
they can’t actually break it down on their own.
They just don’t have the digestive enzymes for it.
But, they’ve made do.
Instead of evolving their own enzymes, they rely on capsid
bugs to do the job for them.
The bugs feed on the trapped organisms and then,
the plant feasts on the capsid’s poop.
Delightful, I love it!
Seeing something like this trapped in amber is always cool,
because plant leaves generally don’t fossilize well.
But this specimen also told scientists something
about the climate this plant lived in.
Before this fossil was found, scientists thought
roridulids originated on Gondwana,
the supercontinent that split up
to make Australia and part of South America, among other things.
But this bit of amber was found in a mine
near Kaliningrad, Russia,
which means that the plants might have been in
the Northern Hemisphere for a while, too.
Since roridula plants don’t do well in the cold,
that suggests the climate in Russia some thirty-five million years ago
was probably warmer than it is today.
Which seems like a lot to learn from one piece of old tree resin.
In 2011, scientists found 11
early forms of feathers, called protofeathers,
hiding in amber specimens from a
museum and a university in Canada.
The protofeathers were from the Late Cretaceous period,
around a hundred to 66 million years ago.
And that was really convenient, because most of
the feathers found before then
were from much earlier in history —
about 146 ——100 million years ago.
So scientists had a gap in their understanding of feather evolution.
That meant that, no matter what,
these amber specimens were going to be useful.
But they turned out to be unbelievably helpful,
because they contained four distinct stages of feather evolution.
First, there were filament fibers which kind of look like hairs,
except, they’re hollow and don’t have scales on their surface.
此外 它们是中空的 表面没有鳞片
Researchers concluded these feathers were really similar to
protofeathers on certain non-avian dinosaurs,
which helped keep the animals warm.
Next, the second stage was a bunch of
these filaments branching out from a base.
Kind of like the protofeathers on some leaping dinosaurs.
These may have been decorative or added stiffness to their tails.
In the third stage, those tufts of filaments fused
to form a central shaft and barbules.
These protofeathers actually looked a lot like
feathers from modern-day grebes.
These diving birds have similar feathers on their bellies to
help them absorb water
and make them less buoyant so they can dive.
So scientists suggest these stage three feathers in amber
may have been from Late Cretaceous diving dinos.
Finally, the stage four feathers looked really similar to those
on many modern day birds,
and could have been used for a range of functions, including flight.
The team thinks they did come from dinosaurs though,
based on the amber’s age and the
similarities to other specimens.
Overall, these researchers pretty much
hit the amber jackpot.
They had believed these four stages existed before,
but with these discoveries,
they essentially got a timeline of how feathers evolved
and how they were used during the Late Cretaceous.
In our last two examples, it was easy to see why
the specimens were cool.
But sometimes, the most amazing part of these discoveries
isn’t as obvious.
That was the case in 2015,
when scientists identified a new species of flea trapped in amber.
The amber came from a mine in the mountains of
the Dominican Republic,
and the flea inside was somewhere between
15 and 45 million years old.
It looked pretty similar to modern fleas,
except with a few extra appendages
and features like small eyes.
But the really cool thing was what scientists found in its mouth.
There, they discovered a group of bacteria
with roughly the same size and shape
as the modern bacterium that caused the bubonic plague.
Yes, that plague, the plague.
Although the researchers couldn’t confirm it,
they think these microbes may be
an ancestor of the bacterium
that caused the infamous fourteenth-century Black Death.
And if that’s true, it means ancient plague strains
may not have evolved as human parasites,
but as rodent ones.
That’s partly because, well, humans weren’t around 15 million years ago.
But also, the ancient bacteria were found in a glob of
dried gunk near the flea’s esophagus
which looks a lot like the glob that forms
when today’s fleas drink plague-infested rat blood.
Scientists found fossilized rodent hairs
at the site where the new flea was discovered, too.
That suggests plagues might have wiped out
way more animals than previously thought ,
and maybe they even contributed to extinctions.
In any case, this isn’t something we would have figured out
if that poor flea hadn’t got stuck
in a bunch of tree resin.
So, Thanks for your sacrifice, flea.
所以 谢谢你的牺牲 跳蚤
Speaking of blood suckers, this next creature is a little less well-known.
It’s called a bat fly.
There are about five hundred species of them,
and they’re like the vampires of the fly
world, because they feed entirely on bat blood.
Or maybe they’re like the vampires of the vampires of the animal kingdom…
In 2011, scientists found a 15 to 45
million-year-old bat fly
stuck in amber from that same mountain
range in the Dominican Republic.
It’s one of only two fossilized
bat flies ever found,
and as is the trend here, that
wasn’t the most interesting thing about this.
It was the fact that, right there on the fly’s midgut,
were two eggs containing an ancient
form of bat-malaria.
And in the fly’s salivary glands, there was also a
spore-like stage of the parasite.
Now, to be clear, when I say “bat-malaria,”
I’m only talking about a malaria strain
that infects bats, not one that affects people.
But studying it is still important for keeping animals safe.
Researchers identified the pathogen as
a bat-malaria ancestor
because those spore-like stages resembled
a modern parasite, with its stubby shape and rounded edges.
Ultimately, this find was kind of surprising to scientists, because one:
ancient bat-malaria, trapped in amber!
That’s a super unlikely, amazing discovery!
But also, before this, researchers thought that only
flies from the Nycteribiidae genus
And this fly in amber was from the other,
closely-related bat fly family,
So this tiny specimen in amber millions of years old
was the first evidence
in both living or extinct bat flies that Streblidae
can also transmit malaria in bats.
Of course, just because no one’s found a living example
doesn’t mean that family
couldn’t transmit bat-malaria today
which is important stuff to know
if we’re trying to keep animals healthy.
Amber really captures a moment in time, and that’s especially true
when it comes to our
next amber artifact.
This piece came from that same Caribbean mountain range
with the flea and bat fly,
a brand-new species of salamander.
Or at least, a brand new species to us.
Because in reality, it’s not new,
it’s been extinct for millions of years.
Scientists classified the new find as part of
the plethodon salamander family,
and it is the only known salamander to ever exist in the Caribbean.
This animal shared a lot of features with modern plethodons,
except for one: It didn’t
have distinct toes like today’s salamanders do.
Instead, it just kind of had little bumps on top of webbing.
That told scientists it probably didn’t climb
as well as its modern counterparts,
and it may have lived in small trees or flowering plants.
Still, like I said, there are no salamanders in the Caribbean today,
and that made researchers wonder how this species got there
in the first place and also where they all went.
Right now, they think this animal’s ancestors may have waded over
to the islands when they were still connected to
South America some forty to 60 million years ago.
Then, they stayed there and later evolved into this plethodon
as the islands broke off.
Alternatively, they could have crossed a land bridge when
sea levels were low, or even floated over on a log
at some point like some species of Caribbean frogs did.
However they got there, though, they certainly didn’t stay.
The Caribbean salamanders probably all died out
because the climate got cooler and drier
some 38 to 23 million years ago.
And that makes this salamander — and this specimen in particular—
pretty darn special.
Finally, the thing that inspired this entire episode, in 2019,
scientists found the hindfoot of a bird
encased in 99 million year old
amber from a valley in Myanmar.
The foot was unusual because its third digit
was much longer than any of its other toes.
And I’m not talking, like, a smidge longer.
而且我说的不是 比如说 长一点儿
This toe was about 40% longer than the other ones,
and about 1/5 longer than its lower leg bone.
When researchers tried to classify this thing,
they were a little stumped.
Because no other bird — living or extinct —
had feet like this.
So they put this animal in a new group
all on its own and called it
meaning “amber bird.”
Names aside, this whole long toe thing was kind of weird,
and scientists are still unsure
exactly why Elektorornis had it.
They suggest in their paper that maybe
it was a tree-dwelling bird, so the long toes
helped it grip branches, and the two really long
toes could help it fish food out of holes in tree trunks.
Part of that is inspired by the fact that the modern aye-aye lemur
also has a similarly long toe.
So this could be a sign of convergent evolution, where similar traits
develop because of similar environmental challenges.
One way or another, this specimen showed scientists that
birds were evolving all sorts of weird
solutions as they branched out into different areas of their environment.
And, like the other examples on this list,
those details might have been lost
if it weren’t for amber.
So, the next time you watch Jurassic Park, go ahead and marvel
at the things tree resin can do.
It definitely won’t be bringing back the dinosaurs any time soon —
because good DNA samples just don’t last that long.
But it is an excellent time capsule.
Thanks for watching this episode of SciShow!
If you enjoy the show and
want to help us create more free content like this,
there are a few ways to support our work —
including becoming a channel member!
Channel members help keep SciShow going,
and as our way of saying thanksfor that,
they also get some perks!
Like cool badges and exclusive
emojis to use in the chat,
and members-only posts in the community tab.
If you’re already a member — or support
SciShow in other ways — thank you!
We’re seriously so glad to have you.
And if you want to learn more about channel memberships,
just click on the “join” button below this video.
琥珀中发现的 6 种神奇事物
Amber is amazing stuff.