Smallest known dinosaur egg found in China sets new record

Vishwam Sankaran
Tue, October 22, 2024 

Smallest known dinosaur egg found in China sets new record


Scientists say fossil dinosaur eggs unearthed at a construction site in China are the smallest ever found, providing new insights into the evolution of the extinct reptile.

The six eggs, fossilised into a lump, were discovered in 2021 in China’s Ganzhou region, which boasts one of the richest deposits of fossilised eggs from a range of ancient reptiles including dinosaurs.

But the fossil eggs found previously in the region were relatively large in size.


After three years of analysis, scientists obtained the overall image of the small eggshells found in 2021 and the fossilised creatures inside them.

The analysis, detailed last week in the journal Historical Biology, confirms that the creatures in the eggs are dinosaurs that roamed the region around 80 million years ago during the Late Cretaceous era.

“We report a partial egg clutch with six complete small eggs from the Upper Cretaceous Tangbian Formation of Ganzhou City,” the study says.

The smallest of the eggs is only about 29mm in length. The previously known smallest dinosaur egg was about 45mm by 40mm by 34mm.

New dinosaur egg fossils discovered in China’s Ganzhou (China University of Geosciences)

The thickness, pores and other features of the eggshells from 2021 are unlike those of any other known for this class of dinosaurs.

This suggests they were laid by a new species from the group of four-legged dinosaurs called theropods. “The egg morphology and eggshell microstructure support it to be the smallest known non-avian theropod egg up to date,” the new study states.

The eggs are now classified in a new category called Minioolithus ganzhouensis, named after the Chinese city they were found in.

“This discovery increases the diversity of dinosaur eggs in Late Cretaceous and is significant for our understanding of the evolution of theropods in the Late Cretaceous,” the study notes.

Researchers plan to continue studying the site where the fossil eggs were found to understand the nature of the dinosaur that laid them as well as how these dinosaurs built their nests.

Tiny fossil tracks unearthed reveal new ways dinosaurs used wings

Vishwam Sankaran
Tue, October 22, 2024

Tiny fossil tracks unearthed reveal new ways dinosaurs used wings


Scientists uncovered strange fossil footprints of a tiny bird-sized feathered dinosaur in South Korea, a discovery that could shed new light on the origin of flight.

The dinosaur, named Dromaeosauriformipes rarus, was a “dinky” two-toed raptor about the size of a modern sparrow, scientists from the University of Maryland in the US said.

The scientists were perplexed by the fossil footprints, which indicated that the dinosaur had giant long strides. “These tracks were a puzzle because their footprints are so tiny but they’re so far apart,” palaeontologist Thomas Holtz, who was part of the team that made the discovery, said.

The discovery was detailed in the journal PNAS.

The dinosaur did not merely run on land but used a strange mechanism that likely paved the way for flight as seen in modern birds.

An artistic rendering of Dromaeosauriformipes rarus (Julius Csotonyi)

There is evidence that the dinosaur flapped its feathered arms to achieve lift, allowing it to travel faster than if it had relied solely on the strength of its legs.

This form of movement, called “flap running”, was somewhere between running and flying and provided the dinosaur with enough force to lift off the ground in bursts, the study noted.

While the force from the movement would have enabled the dinosaur, an ancestor of modern birds, to likely run up a tree, it fell short of full-powered flight, scientists said.

“We can now move past the debate about whether pre-avian dinosaurs used their arms to help them move before flight evolved and start to uncover missing details such as which species had these abilities and when and to what extent they were developed,” Michael Pittman, another author of the study, said.

The researchers initially suspected the fossil footprints could have been made by a dinosaur with long, stilt-like legs akin to a “a Dr Seuss character”.

They also tested the theory that the animal could have just been “extremely fast”.

After considering the dinosaur’s hip height, they estimated that the speed needed to achieve the long strides would be about 10.5 metres per second.

This is more than the speed of any living running animal, including ostrich and cheetah, making it “highly improbable” the footprints were left by any of them, the researchers said.

Likely path taken by dinosaur D rarus as it left footprints (Alexander Dececchi et al PNAS)

They concluded that the trackway was produced at lower speeds with the dinosaur elongating its stride length using the force generated by the flapping of its feathered arms.

The unique footprints, scientists said, were left “in the midst” of the dinosaur taking off or landing.

“Thus the origin of flight may not be a simply binary of ‘can or cannot’ but a spectrum,” the study said.

“It is kind of like when a plane is coming down and bounces a little bit on the runway before slowing down,” Dr Holtz explained.

The latest research could inspire a closer look at similar dinosaur trackways in Bolivia or Madagascar or Australia. “There’s no reason to suspect these trackways were only in East Asia during the early Cretaceous, so we are hoping that people will look at their footprint slabs and find something else,” Dr Holtz said.