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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 plague 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 that a plant releases when it’s damaged. Then, when the resin hardens, the creature gets pretty much mummified.

Like, seriously. 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 that 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 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.

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 plants feast on the capsid’s poop.

Delightful, I love it! Now 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 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.

This all 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.

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 of 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 that help 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 for 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. 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 that 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. 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. 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. So I guess 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. The interesting part was 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

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 super unlikely and amazing! But also, before this, researchers thought that only flies from the Nycteribiidae genus spread bat-malaria. And this fly in amber was from the other, closely-related bat fly family, called Streblidae.

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 to 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 the same Caribbean mountain range with the flea and bat fly, and it held 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 this new find as part of the plethodon salamander family, and it’s 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 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 little longer, like middle finger longer.

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 new animal in a group all on its own and called it Elektorornis chenguangi, 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 really long toes would help them 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 big long toe.

So this could be a sign of convergent evolution, where similar traits develop because of a similar environmental challenge. 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 some 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 dinosaurs any time soon — because good DNA samples just don’t last that long. But it is a very efficient time capsule.

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