Paleontology: Fossilized remains found of a dinosaur sitting on an egg nest with embryos inside

[ad_1]

The fossilized remains of a dinosaur sitting on an egg nest, with embryos kept inside, have been unearthed in China, a study reported.

The discovery – a world first – is an oviraptorosaur, one of a group of theropod bird-like dinosaurs that flourished 130 to 66 million years ago, during the Cretaceous Period.

According to experts, the specimen in question was found in 70 million-year-old rocks excavated near the train station in Ganzhou City, Jiangxi Province.

The adult oviraptorosaur has been partially preserved by incubating above the clutch of at least 24 eggs, at least seven of which contain skeletal remains of the unhatched young.

The late development of embryos allowed paleontologists to rule out the possibility that the adult died while laying eggs.

Instead, the discovery suggests that oviraptorosaurs incubated their nests like their modern bird cousins - rather than just guarding their nests crocodile-style.

This was supported by analyzes of the oxygen isotopes of the eggs, which indicated that they were incubated at high temperatures, just like the eggs of modern birds.

The fossilized remains of a dinosaur sitting on an egg nest, with embryos kept inside, have been unearthed in China, according to a study.

The adult oviraptorosaur has been partially preserved by incubating above the clutch of at least 24 eggs, at least seven of which contain skeletal remains of the unhatched young. In the photo: a photograph of the fossilized specimens, on the left, and in the illustration, on the right

“This type of discovery – essentially fossilized behavior – is the rarest of the few in dinosaurs,” said author and vertebrate paleontologist Matthew Lamanna of the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.

“ Although a few adult oviraptorids have already been found on nests of their eggs, no embryos have ever been found inside these eggs. ”

“ In the new specimen, the babies were almost ready to hatch, which no doubt tells us that this oviraptorid had maintained its nest for quite a long time. ”

“This dinosaur was a caring parent who ultimately gave his life while feeding his young,” he concluded.

Analysis of the fossil embryos revealed that although all were well developed, some had reached a more mature stage than others, suggesting that if they had not been buried and fossilized, they would likely have hatched in slightly different times.

This characteristic – which experts call the “ asynchronous hatching ” – appears to have evolved independently in oviraptorid dinosaurs and some modern birds, the researchers explained.

The team also found a cluster of preserved pebbles in the abdominal region of the adult oviraptorid, which they say are gastroliths, or “ stomach stones, ” which were said to have been swallowed to help the dinosaur digest. his food.

This is the first time that verified gastroliths have been found preserved in a fossilized oviraptorid and may thus lead to new knowledge about their diet.

The late development of embryos allowed paleontologists to rule out the possibility that the adult died while laying eggs. Instead, the discovery suggests that oviraptorosaurs incubated their nests like their modern bird cousins - rather than just guarding their nests crocodile-style. Pictured is a cross-sectional drawing of the adult oviraptorosaur skeleton (with bones preserved in white) incubating its clutch of eggs

Analysis of the fossil embryos (pictured) revealed that while all were well developed, some had reached a more mature stage than others, suggesting that if they had not been buried and fossilized, they would likely have hatched at slightly different times.

“It is extraordinary to think of the amount of biological information captured in this single fossil,” said vertebrate paleontologist Xing Xu of the Chinese Academy of Sciences in Beijing.

“We will learn from this specimen for many years to come,” he added.

The full results of the study were published in the journal Science Bulletin.

The specimen in question was found in 70-million-year-old rocks excavated near the train station in Ganzhou City, Jiangxi Province.

HOW DINOSAURS WERE EXTINCT 66 MILLION YEARS AGO

Dinosaurs ruled and dominated Earth about 66 million years ago, before they suddenly vanished.

The Cretaceous-Tertiary extinction event is the name given to this mass extinction.

It was believed for many years that climate change had destroyed the food chain of huge reptiles.

In the 1980s, paleontologists discovered a layer of iridium.

It is a rare element on Earth but found in large quantities in space.

When this was dated, it coincided precisely with the disappearance of the dinosaurs from the fossil record.

A decade later, scientists discovered the enormous Chicxulub crater at the tip of Mexico’s Yucatán Peninsula, which dates back to the period in question.

Scientific consensus now says that these two factors are related and that they were probably both caused by a huge asteroid crashing into Earth.

With the size and velocity of impact projected, the collision would have caused a huge shock wave and likely triggered seismic activity.

The fallout would have created plumes of ash that likely covered the entire planet and made it impossible for the dinosaurs to survive.

Other animals and plant species had a shorter time interval between generations, which allowed them to survive.

There are several other theories about what caused famous animals to disappear.

One theory was that small mammals ate dinosaur eggs and another suggested that poisonous angiosperms (flowering plants) were killing them.

[ad_2]

Source link