Studying prehistoric times can be a challenge. We humans tend to leave a lot of stuff behind that shows we were there, but things were different before we came along.
That is where fossils come in, a paleontologist’s best friend. To put it simply, fossils are preserved remains of ancient organisms. Most of them are bones, shells, or exoskeletons, which have been petrified and preserved in rock, but other organic materials could also have been saved in amber, petrified wood, or tar pits.
Today we take a look at some of the most bizarre fossils that have ever been recovered.
10. The Denisovan Jaw
For Tibetans, the Baishiya Karst Cave is a holy place of healing, but for paleoanthropologists, it has become one of the most puzzling places on the planet, one that likely holds answers regarding one of the most mysterious species of proto-humans – the Denisovans.
This little saga started in 1980 when Buddhist monks found a strange fossil. It was a mandible with two large teeth. It looked human but, at the same time, not entirely human. Fortunately, the monks realized that it was probably an important discovery, so they saved it and the fossil eventually made its way to scientists in China. However, those scientists were not paleoanthropologists and they didn’t make much of the jawbone but decided to hold onto it.
Thirty years later, in 2010, we discovered the Denisovans, an extinct species of humans closely related to Neanderthals, based entirely on a few small bones found in a cave in Siberia called Denisova. That was when scientists remembered the mysterious jawbone and began studying it. In 2018, they publicized their findings – the Xiahe mandible, as it came to be known, was also of Denisovan origin. To this day, it is not only the largest Denisovan fossil in the world, but also the only confirmed one that has been found outside Denisova Cave.
9. The Fighting Dinosaurs
Some unusual fossils, like the aforementioned Xiahe mandible, are notable because they reveal to us something new about an extinct species. Others, however, are simply interesting and provide us with a unique glimpse into the prehistoric past. That is the case with the fighting dinosaurs, a pair of fossils recovered from the Mongolian desert back in 1971.
These two animals – one predator, one prey – were engaged in deadly combat 75 million years ago when a sudden event, most likely a collapsing sand dune, preserved them for eternity in their desperate struggle for survival.
The predator was the famed Velociraptor, while its target was a boar-sized herbivore called a Protoceratops. The raptor appeared to have stuck one of its sharp claws deep into the neck of its prey – most likely a lethal hit, even if not instantaneous. But the Protoceratops did not go down without a fight. It had thrown its attacker to the ground and bit down hard on one of the raptor’s arms, breaking the bone. Some paleontologists speculate that their demise might not have been due to a sudden sand flow, but that the heavy herbivore died on top of the wounded Velociraptor, leaving it unable to move and, thus, sealing both of their fates.
8. The Oldest Fossil
When it comes to fossils, there is no title more coveted than “the oldest fossil in the world.” While we can’t tell you with certainty which one deserves that moniker, since it is debatable, we can tell you which one claims to be the oldest – ancient fossils from Greenland purported to be 3.7 billion years old.
The fossils in question are stromatolites – sedimentary formations just a few centimeters tall caused by billions of bacteria grouped together. They were found in 2016 in an ancient rock formation from Greenland known as the Isua Greenstone Belt.
Supporters of the discovery hail it as the “oldest direct evidence of microbial life” on the planet. However, controversy stems from the fact that detractors argue that the formations could have appeared through natural processes in the right conditions, so they are not 100 percent indicative of life. The debate continues, but if the Isua fossils prove to be genuine, they would be 220 million years older than the previous oldest-known fossils, which were discovered in Western Australia.
7. The Dino Nest
Despite our obsession with dinosaurs, there are several areas regarding their lives where we are still completely in the dark, and one of those is how they raised their offspring. We used to think that dinosaurs did not display any parental care whatsoever – once you hatched, you were on your own. However, that changed a decade ago, when paleontologists found the remains of 15 fossilized dinosaur babies nesting together.
Discovered in Mongolia, the fossils are around 70 million years old and all constitute juvenile members of Protoceratops andrewsi who met their end when they were buried under an ancient sand dune. The whole nest was round, bowl-shaped, and around 2.3 feet in diameter. The fact that all the baby dinosaurs were growing together inside the same nest suggests that some species of dinosaurs provided parental care, at least in the early stages of post-natal development.
6. The Snake and His Lunch
Even if some dinosaurs were protective parents, it appears that sauropods, the giant ones with long necks, were not among them. Instead, it seems like the adults abandoned their nests once they laid their eggs and left their future offspring to their fate. One baby dinosaur learned this the hard way, as it was about to be eaten by a giant snake when a landslide buried them all, making for a highly unexpected and disturbing discovery 68 million years later.
The fossils were first found by an Indian geologist in 1987. He identified the nest as belonging to sauropods and assumed that all the bones lying around belonged to hatchling dinosaurs. It wasn’t until 2010 that paleontologists who studied the fossils revealed that some of the remains came from an ancient snake called Sanajeh indicus.
Unlike its modern cousins, this prehistoric reptile could not stretch its jaw wide to swallow giant eggs. At the same time, it also could not break open their thick shells. So what it did was coil around an egg, wait for it to hatch, and then devour the newly-born dinosaur. That was the plan here, and the snake was ready to pounce on the baby sauropod that had just emerged out of its shell when a landslide entombed both prey and predator.
5. The Frisky Flies
Jurassic Park has shown us all the value of amber, a fossilized resin that can preserve life from millions of years ago. In real life, we have yet to obtain any “dino DNA” from amber, but it has yielded some incredible finds, as detailed by one research team from Australia’s Monash University who presented their results in 2020 after studying over 5,800 amber samples dated to anywhere between 40 million and 230 million years ago.
The team uncovered a lot of interesting fossils, but the most unique and bizarre one has to be one piece of amber that captured two long-legged flies from the family Dolichopodidae who were in the middle of mating when they became trapped in the sticky sap, with their moment of intimacy preserved for eternity in resin.
Lead researcher Jeffrey Stillwell considers amber to be the “Holy Grail” of paleontology, pointing to the fornicating flies as an example of creatures that died approximately 41 million years ago, that look “just like they died yesterday.”
4. The Predator Becomes Prey
Star Wars taught us that there is always a bigger fish. In this case, the expression can be taken quite literally, as one pterosaur found out to its own expense 155 million years ago.
The creature in question belonged to the genus Rhamphorhynchus which, at approximately 20 inches long, was one of the smaller examples of pterosaur. One day, the flying reptile swooped into the water and caught a fish, but just as it was swallowing it, the predator was itself caught by a larger, 2-foot long fish named Aspidorhynchus.
Despite the size advantage, it seems that the fish was ill-equipped to handle prey the size of Rhamphorhynchus, and its teeth got caught in the tough, leathery fibers of the pterosaur’s wing. Unable to disentangle itself, Aspidorhyncus sank to deep, low-oxygen waters together with its prey, which still had the small fish in its throat, and all three of them died on the bottom of the lagoon together, preserved as a fossil for 150 million years.
3. The Tully Monster
In the summer of 1955, amateur fossil hunter Francis Tully made one of the strangest discoveries in the history of paleontology in Mazon Creek, Illinois. It was a fossil unlike any other, that immediately defied classification and still puzzles scientists to this day.
The animal was named Tullimonstrum gregarium, although it became better known as the Tully Monster, and it is around 300 million years old. Numerous other specimens have been found since then, but all of them in the fossil beds of Mazon Creek. Therefore, paleontologists have a pretty good idea of what the Tully Monster looked like, they just don’t know what it was.
The Tully Monster had a soft, slug-like body that ended in a spade-shaped tail with fins. At the other end, it had a long, tube-like proboscis that ended in a mouth with sharp teeth that was more reminiscent of a claw. Strangest of all, the eyes were on stalks, located around halfway down the body.
Scientists have been studying the Tully Monster for 65 years, but they are still unsure if it was a vertebrate or invertebrate, let alone what kind of family or genus it belonged to. In 2016, a study published in Nature presented strong evidence to classify the strange creature as a vertebrate, part of the same lineage as lampreys. However, other studies have appeared in the years that followed which contradict their conclusions, so the origins of the bizarre Tully Monster remain very much a mysterious and controversial topic.
2. The Tiny Vampires
It seems that even 750 million years ago, when all life on the planet consisted of single-celled organisms, creatures still hunted and killed each other. That is the conclusion of a study published by the Royal Society in 2016 which found the earliest evidence of predation in the fossil record, caused by tiny vampire-like organisms.
The fossils did not reveal the killers themselves, but rather their victims – microscopic eukaryotes that had circular and half-moon-shaped holes in their membrane. These were the result of attacks by predatory organisms which pierced the outer skin so that they could feed on the juicy nucleus inside.
Predation was one of the driving factors that led to the evolutionary arms race between predator and prey, which eventually caused the incredible diversification of life that resulted in all the creatures on this planet. If these tiny vampires didn’t start eating other organisms hundreds of millions of years ago, life today might be nowhere near as complex as it is and humans might not even exist.
1. The Titillated Arachnid
We’ve already mentioned the mating flies stuck in amber, but an even stranger fossil involves a daddy longlegs that got trapped in the resin almost 100 million years ago. This situation was amorous, as well, even though just the male got stuck in his sticky tomb this time. We know it was amorous because the arachnid was preserved sporting a fully erect penis.
Even though we usually mistake them for spiders, daddy longlegs or harvestmen belong to a separate group of arachnids called Opiliones. The two groups differ because harvestmen have genuine penises, while most spiders have special organs called “pedipalps.” It seems that this particular daddy longlegs belonging to the extinct species Halitherses grimaldii was getting ready for some action when he got entombed by oozing tree resin in what became a piece of amber. That is why even now, 100 million years later, we can see his erect penis, which measures around half a millimeter and has been described as having “a heart-shaped tip and a bit of a twist at the end.”