Tag Archives: geese

The ancient ancestors of geese are the earliest recorded modern birds

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Vegavis Iaai was an ancient relative of ducks and geese, but it dived for fish like graves and runes

Mark Whitton

The 69 million-year-old skull found in Antarctica is identified as a relative of geese and ducks, making it the oldest known modern bird.

It belongs to the first identified species named 20 years ago Vegavis Iaai, He lived alongside the last dinosaurs in the late Cretaceous period. However, only fragments of the skull had been discovered previously, so scientists were unable to agree on what kind of bird it was, or whether it was a non-vian dinosaur like a bird instead.

The fossil skull was discovered in 2011 on Vega Island off the coast of Antarctic Peninsula. However, it was enveloped in such a fierce rock that the excavator had to scrape away the surrounding stones for hundreds of hours before scanning to reveal details about its interior.

Patrick O'Connor At Ohio University, which worked on the analysis, it says that two almost perfect skull features occur only in modern birds. First, the upper beak is made up of bones, which are primarily called the anterior axis, and the size of the second bone, the maxilla, is significantly reduced, contributing only to a small portion of the bone-palate.

Second, in modern birds, the forebrain is huge compared to the rest of the brain. Like pre-modern birds and dinosaurs of nearby birds Velociraptorthese areas are proportionally much smaller.

meanwhile Vegavis According to O'Connor, it has the ability to clearly mark it as being in the same group of waterfowls as ducks and geese. The bird's beak shape, jaw muscle tissue and hind legs suggest that they were very specialized in diving into the pursuit of fish.

“Perhaps you can easily mistake it for modern graves and runes. This is only related to ducks and each other,” he says.

Jacqueline Nguyen The Australian Museum in Sydney says that this ancient species has been the subject of many debate among bird evolutionary scientists, but new research will help resolve the debate.

“together, [the evidence] It suggests that Vegavis It looks completely different from the duck and geese parents, and this could have been an “evolutionary experiment” in the early history of this group of birds.” says.

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Source: www.newscientist.com

Ancient geese reached the height of three meters and weighed as much as a cow

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Artistic reconstruction of Genyornis newtoni, an ancient relative of the goose

Illustration by Jacob C. Blokland

Australia's prehistoric ptarmigan, once thought to be an ancestor of the emu, was actually the largest goose that ever lived.

This group was reclassified based on analysis going back 45,000 years. Genyornis neutoni The skull was found in the fossil deposits of Lake Carabonna in the South Australian desert.

The newly discovered skull is the first of the extinct species to be discovered since 1913, and the only one well-preserved enough to allow detailed anatomical study. G. Newton He weighed approximately 230 kilograms and was over 2.5 metres tall.

However, its close relativesDromornis stiltoniAt well over three metres tall and weighing up to 600 kilograms, it is not only a contender for the largest bird in history, but also the largest goose ever.

When Thunderbird fossils were first discovered in the 19th century, they were thought to be ancestors of ratites, which include emus, cassowaries and ostriches. Later, some argued that the group, officially called Dromornithiidae, with eight known species, should be classified with land birds, which also include chickens and pheasants.

now, Phoebe McInerney Researchers from Flinders University in Adelaide, Australia, concluded that the Thunderbird is a large waterbird and should be classified as part of the Anseriformes, the same group as geese.

The team was primarily convinced by the anatomy of the beak and skull, including the arrangement of muscles and the deformation of the bones to which they were attached. Genyornis The structure is nearly identical to that of South American screamers, an ancient lineage of waterbirds, and is so complex that it's unlikely it evolved independently, McInerney said.

Artistic reconstruction of the skull of Geniornis newtoni based on fossil data

Illustration by Jacob C. Blokland

All of the ptarmigans were herbivores, she says, but they were probably fierce creatures. “They would have been very tough animals,” McInerney says. “They could defend themselves and they would have been quite formidable beasts. They would have had a very low, loud cry.”

Adam Yates Yates, of the Northern Territory Museum and Art Gallery in Australia, said the study supports the claims of his predecessor, Peter Murray, who proposed in the early 1990s that the Thunderbird was a waterbird. “So it's not a shock to me,” Yates said. “But Genyornis It took so long to find the skull, so we're very happy that it has finally been found.”

Many Thunderbird species became extinct before humans arrived in Australia around 65,000 years ago, which is thought to have been due to climate change.G. Newtoni Humans had inhabited the continent for tens of thousands of years, and some researchers speculate that hunting may have also played a role in their extinction.

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Source: www.newscientist.com