Did kraken-like octopuses rule Cretaceous seas? Massive jaw fossils offer clues

In the age of dinosaurs, giant octopuses — sometimes named krakens after the mythological monsters — might have grown to nearly 19 metres in length. The estimate is based on fossilised jaws, which researchers say show patterns of wear that came from devouring animals that had hard shells and skeletons. The team suggest that these giant cephalopods might have sat at the top of the marine food chain in the Cretaceous period alongside huge marine reptiles such as mosasaurs. But other researchers say that estimates about the size of the soft-bodied creatures, and how they hunted, should be taken with a pinch of salt.

Canadian fossil reveals one of the first plant-eating animals

A fossilised skull dated to more than 300 million years ago has been identified as belonging to Tyrannoroter heberti, a newly described ‘microsaur’ species and one of the oldest-known vertebrate herbivores. From a 3D reconstruction of the skull, researchers found that the species had specialised teeth that resemble those of other plant-eating animals and that had been worn down from a grinding motion consistent with herbivory. The discovery suggests that vertebrate herbivores emerged around several million years earlier than scientists had previously estimated.

Wolf pup’s stomach yields DNA from one of world’s last surviving woolly rhinos

A genomic analysis of around 14,400-year-old woolly rhino (Coelodonta antiquitatis) tissue — recovered from the stomach of an ice age wolf (Canis lupis) — has revealed clues as to the cause of the species’ rapid extinction around 14,000 years ago. Researchers compared the animal’s genetic diversity to genomes belonging to older woolly rhino samples and found no evidence of inbreeding, which suggests the species’ downfall was not a long, gradual process. The team instead proposes that a warming climate destroyed the rhinos’ habitat, which caused a swift population collapse.

How did birds evolve?

For more than a century, Archaeopteryx was the earliest known bird genus, and the only one known from the Jurassic period, when birds first evolved. Last year, fossils of a newly discovered genus revealed that Archaeopteryx wasn’t alone: a creature called Baminornis also walked the Jurassic Earth — and flew as well. These two genera of birds are so different that some researchers suggest that the first birds predated them both. The findings are revealing clues about how and why birds evolved, and hint that the evolutionary story of birds has an even earlier chapter than researchers thought.

This Fossil Is Rewriting the Story of How Plants Spread across the Planet

The first plants to get a foothold on land are a mystery, because there are few fossils — except for Spongiophyton. But the enigmatic lifeform has been fiendishly difficult to classify. Now a beautifully preserved specimen has revealed itself as one of the oldest lichens in Earth’s history, showing that these organisms were already common more than 410 million years ago. “It’s a major shift in how we view the complexity of life’s first steps onto land,” says palaeobiologist and study co-author Bruno Becker-Kerber. Spongiophyton “likely weathered rocks, stabilised sediments, cycled nutrients and contributed to the formation of protosoils just before forests developed”.

‘Teenage T. rex’ fossil is actually a different species

A fossil once assumed to be of a young Tyrannosaurus rex is in fact that of a fully grown adult of a different species altogether. The species, christened Nanotyrannus, is about half the length and one-tenth of the body mass of its larger cousin. The specimen also has distinct physical features such as longer arms and sharper, less curved teeth than T. rex. The classification of Nanotyrannus is a “mic drop”, says palaeontologist Steve Brusatte. “And that necessitates a fundamental reassessment of tyrannosaur classification and evolution.”

Dinosaur egg dated directly for the first time

Scientists have calculated the age of a fossilized dinosaur egg from analysing the minerals deposited on the surface during fossilisation (it’s around 85.9 million years old). This is the first time a dino egg has been dated directly, rather than relying on indirectly dating the volcanic ash or rock layers in which the specimens are embedded. “This will remove the uncertainties associated with the ages of many fossils,” says palaeontologist Guntupalli Prasad. However, the study did not account for the processes that occur between the egg’s burial and fossilisation, notes palaeontologist Susannah Maidment.

Ancient proteins rewrite rhino family tree

Proteins extracted from the remains of an extinct rhino species (Epiaceratherium itjilik) are among the most ancient ever sequenced. From a sample of enamel from the 23-million-year-old fossil, researchers were able to partially sequence 7 proteins. Integrating these proteins with genome data places Epiaceratherium in a new branch of the rhino family tree — one that split off between 41 million and 25 million years ago. The findings suggest that proteins survive better than researchers thought. This raises the possibility of gleaning molecular insights about evolutionary relationships, biological sex and diet from even older animals — maybe even dinosaurs.

First ever skull from ‘Denisovan’ reveals what ancient people looked like

Ancient proteins and mitochondrial DNA extracted from the ‘Dragon Man’ fossil — a cranium found in northeastern China that is at least 146,000 years old — have confirmed that it belonged to a Denisovan, an archaic human group. The fossil is the first skull to be definitively linked to the group, which sheds light on what the ancient people looked like, putting an end to decade-long speculation.

Early Neanderthal Art Discovered

A close examination of the red ochre dot on this stone, unearthed from the San Lázaro rock-shelter in Spain, revealed that the mark was made by a human finger. This raises the tantalising prospect that a Neanderthal maybe, just maybe, meant the dot to represent a nose (the rock, say researchers, does indeed look like a face in person). “It could represent one of the earliest human facial symbolisations in Prehistory,” write the team that made the discovery.

Who were the ancient Denisovans? Fossils reveal secrets about the mysterious humans

In 2008, a tiny fingertip rewrote human history when DNA sequencing revealed that it belonged to a previously unknown group of hominins: Denisovans. Further research revealed that they interbred with modern humans and were once widespread across Asia. In the past few years, more fossils have emerged that are helping to flesh out who Denisovans were and how exactly they fit into our family tree.

Fossil claw marks show reptiles arose much earlier than thought

Fossil claw prints found in Australia were probably made by the earliest known amniotes — the group that includes reptiles, birds and mammals. The findings push the origin of this group back to around 35 million years earlier than was previously thought. There are no marks of dragging bellies or tails, which could hint that the animals were able to hold their bodies up while they walked — an indicator that they had evolved for complex movement.

Mysterious Taiwan fossil is Denisovan

A fossilised jawbone discovered more than 20 years ago belonged to an ancient group of humans called Denisovans. Named Penghu 1, the jawbone was dredged up by fishing crews 25 kilometres off the west coast of Taiwan. The confirmation that the bone belonged to a Denisovan — the result of more than two years of work to extract ancient proteins from the fossil — expands the known geographical range of the group, from colder, high-altitude regions to warmer climates.

Mongolian dinosaur wielded 'big, sharp and nasty' claws

Fossils discovered in Mongolia have revealed an unusual new species of dinosaur. Duonychus tsogtbaatari falls into a group of giant-sloth-like dinosaurs called therizinosaurs, but with one unique feature: every therizinosaur discovered so far had three, clawed fingers; Duonychus, as its name suggests, only had two. The fossil’s remarkably-preserved claws were around 30 cm long, and researchers say the dinosaur wasn’t fully grown.

Jurassic mammals’ fur colour revealed for first time

Fossils that preserve the details of Jurassic and Cretaceous mammals in spectacular detail have allowed scientists to determine, for the first time, the likely colour of their fur. Researchers analysed tiny structures in the hair of a previously undescribed flying-squirrel-type creature — which they dubbed Arboroharamiya fuscus — and five other mammal fossils from what is now northeastern China. Compared with the hair of modern mammals, the shape and size of the structures suggest that the ancient animals were dark-coloured.

Ancient humans used bone tools one million years earlier than thought

Bone tools discovered in Tanzania reveal that ancient humans consistently used such tools at least one million years earlier than we thought. The previous estimate put the earliest use of bone tools at around 400,000 years ago. The new findings smash that record, dating the implements to around 1.5 million years ago. The utensils were crafted from elephant, hippopotamus and bovine bones, and were probably used for tasks such as butchering and digging out tubers.

Where dinosaurs come from

Dinosaurs might have first evolved near the equator in Gondwana — a portion of the supercontinent Pangaea that today exists as northern South America and northern Africa. Researchers used computer modelling to analyze three proposed evolutionary trees, based on characteristics such as the ability to generate their own body heat. “These specialised traits didn't appear overnight,” says palæontologist Joel Heath, who co-authored the research. “However, we haven't yet found the transitional fossils that show how these changes happened.” The model accounts for gaps in the fossil record by factoring in the likelihood that plenty of fossils have yet to be discovered — especially in difficult-to-explore places.

Neanderthals and sapiens interbred more recently than previously thought

All people, other than those whose ancestry comes solely from sub-Saharan Africa, have some Neanderthal DNA. Now two studies suggest that it entered our genomes virtually overnight, much more recently than was thought. One study finds that modern humans and Neanderthals interbred in a roughly 7,000-year period starting around 50,500 years ago; the other finds that the mixing took place between 45,000 and 49,000 years ago. The results and other insights come in part from the oldest human genomes ever sequenced: a male Homo sapiens found near Ranis, Germany, and a female Homo sapiens whose remains were discovered in a cave at a site called Zlatý kůň in the Czech Republic.

Two ancient human relatives crossed paths 1.5 million years ago

Some 1.5 million years ago, two ancient hominin species crossed paths on a lake shore in Kenya. Their footprints in the mud were frozen in time and lay undiscovered until 2021. Now, analysis of the impressions reveals that they belonged to Homo erectus, a forebear of modern humans, and the more distant relative Paranthropus boisei. The two individuals walked through the lake area within hours or days of each other — leaving the first direct record of different archaic hominin species coexisting in the same place.

Bromalites show how dinosaurs rose to rule Earth

By analysing fossils of poo and vomit, researchers have reconstructed what dinosaurs ate and how this changed over time. The findings give a better understanding of how dinosaurs became so dominant, revealing that their rise, over millions of years, was influenced by factors including climate change-induced shifts in what vegetation was available, which the dinosaurs were able to adapt to better than other animals. The contents of the fossils became more varied over time, suggesting that larger dinosaurs with more diverse feeding habits began to gain prominence in the late Triassic period a little over 200 million years ago.