Bizarre ancient creatures looked like huge aquatic plants, but they were actually animals

Fossil hunting isn’t quite as cut-and-dry as you might think it is. Finding the leftovers of a creature that lived a hundred million years ago is exciting, and while dinosaurs and many plants are relatively easy to identify based on their remains, creatures from even farther back in Earth’s history have left scientists scratching their heads.

One group of organisms which got its start in the Ediacaran period — roughly 500 million years ago, or so — looked a bit like oversized leaves that could measure up to two meters in length. Long-studied, these organisms confounded researchers for years, with scientists unable to determine if they were indeed plants or animals, or maybe something in between. Now, new research points to them indeed being animals, albeit ones that seem utterly alien here on Earth.

The study, which was published in Palaeontology, was conducted by researchers from multiple universities around the world, closely examined known fossils of a species called Stromatoveris psygmoglena. The creatures looked like large, ribbed leaves on the ancient ocean floor, but after examining over 200 known examples of the creature it’s become apparent that they were actually just really, really weird animals.

The researchers reached their conclusion by using a computer model which makes an educated guess as to where a species might reside on the evolutionary tree. Using all the data as their disposal, the scientists now believe that these organisms may have been an entirely new phylum of the animal kingdom, more complex than simple sea sponges but not as advanced as animals with full digestive systems.

These animals do not appear to have evolved into any other known organisms, so it seems like the entire group ran into a brick wall after thriving for tens of millions of years. Researchers still don’t know exactly why they went extinct, and figuring that out might indeed be impossible. Nevertheless, it’s an interesting discovery, and helps researchers paint a clearer picture of what the world was like half a billion years in the past.

Bizarre ancient creatures looked like huge aquatic plants, but they were actually animals

Ancient Cave Bears From Europe Were Vegetarians

The Pleistocene epoch, a period famed for terrifying creatures like cave lions, dire wolves and saber-toothed cats and other weird animals during the last ice age has a very different creature: vegetarian cave bears.

Yes, you read that right. There was once a huge bear known as Ursus spelaeus, which roamed Europe and snacked on fruits and nuts instead of meat!

Except for the cuddly panda, we don’t see bears as not having humans on their menu. But researchers long believed that cave bears also ate some plants because they had the dentition for it. Their teeth were suited for grinding plants and not slashing meat.

Checking out the dentition of the cave bear, researchers from Germany and Spain found out that the direct ancestor of the cave bear – the Deninger’s bear “had very similarly shaped mandibles and skull to the classic cave bear,” said the lead author of the study, Anneke van Heteren.

Over 500 Thousand Years Ago, Cave Bears Had a Different Diet

The Deninger’s bear adapted long ago to a new diet explained the co-author of the study, Mikel Arlegi:

“There is an ongoing discussion on the extent to which the classic cave bear was a vegetarian. And, this is especially why the new information on the diet of its direct ancestor is so important, because it teaches us that a differentiation between the diet of cave bears and brown bears was already established by 500 thousand years ago and likely earlier.”

However, even if this bear didn’t enjoy munching on meat, this doesn’t mean that you could freely enter his cave! They might have preferred fruits or nuts, but they could also defend their territory – his huge frame would be terrifying enough! Nonetheless, it’s good to know that the Pleistocene epoch had a gigantic vegetarian among so many giant predators.

Ancient Cave Bears From Europe Were Vegetarians

Russian Scientists Claim to Have Resurrected 40,000-Year-Old Worms Buried in Ice

A team of Russian scientists is lining themselves up to be the opening cast of a John Carpenter film. Earlier this month, in the journal Doklady Biological Sciences, they announced they had apparently discovered ancient nematode worms that were able to resurrect themselves after spending at least 32,000 years buried in permafrost. The discovery, if legitimate, would represent the longest-surviving return from the cold ever seen in a complex, multi-celled organism, dwarfing even the tardigrade.

The worms were found among more than 300 samples of frozen soil pulled from the Kolyma River Lowlands in Northeastern Siberia by the researchers. Two of the samples held the worms, with one from a buried squirrel burrow dating back 32,000 years and one from a glacier dating back 40,000 years.

After isolating intact nematodes, the scientists kept the samples at 68 degrees Fahrenheit and left them surrounded by food in a petri dish, just to see what would happen. Over the next few weeks, they gradually spotted flickers of life as the worms ate the food and even cloned new family members. These cloned worms were then cultured separately, and they too thrived.

It’s definitely not out of the question that these worms could have been revived after so long, according to Robin M. Giblin-Davis, a nematologist and acting director of the Fort Lauderdale Research and Education Center at the University of Florida.

“Theoretically, it is possible that if the organisms are protected from physical damage that would compromise their structural integrity during their frozen internment, they should be able to revive upon thawing/rehydration for very long periods of time,” he told Gizmodo via email.

At the same time, the team’s findings could still be a dud. “The biggest issue is the potential for contamination of ‘ancient samples’ with ‘contemporary’ organisms,” he said.

While the researchers do admit the possibility of contamination in the paper, they say it’s unlikely. They cited strict procedures to ensure complete sterility. And given that the ice samples were buried 100 feet and 15 feet down, respectively, they argue it’s implausible modern day nematodes could have wormed their way that deep.

The researchers identified some of the worms in the 32,000-year-old sample as belonging to the genus Panagrolaimus, and some of the worms in the 40,000-year-old as part of the genus Plectus. Byron J. Adams, a nematologist at Brigham Young University who has studied nematode species capable of surviving extreme conditions, said the researchers’ claims seem credible, based on what we know about the biology of some modern-day nematodes.

“I’d love for it to be true,” Adams told Gizmodo. “We see what we think are prolonged stasis in Plectus and Panagrolaimus in Antarctica but have difficulty carbon dating them.”

The discovery of such long-lived creatures would be an astounding record-breaker. Ancient bacteria buried in salt crystals over 250 million years ago supposedly have been brought back to life, but the oldest thawed-out animals only date back decades at most, such as a group of tardigrades, otherwise known as the water bear, that were resurrected after 30 years on ice.

The more complex nature of these allegedly ancient nematodes could reveal more insights about the feasibility of cryostasis or how to survive in extreme conditions like space, the researchers speculated. And at the very least, they might provide clues as how these worms have evolved over time.

“After 40 thousand years, we should expect to detect significant differences in evolutionary divergence between ancient and contemporary populations,” Adams said.

Adams was careful to point out that because we know so little about the genetics of these modern cold-loving worms, even a genetic comparison that finds substantial differences between the thawed-out worms and other present-day populations wouldn’t necessarily confirm their longevity. He believes it will take very sophisticated tests, akin to those that confirmed the existence of nematode species that can survive deep inside the crust of the Earth, to know whether these worms are actually ancient.

Russian Scientists Claim to Have Resurrected 40,000-Year-Old Worms Buried in Ice