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Scientists think they have solved the mystery of 99 million year old fossils



In 2016, researchers announced A landmark discovery made at a site in Myanmar: They found 99 million-year-old chameleons preserved in amber.

Fossils preserved in amber give a much clearer view of the ancient animal kingdom than fossils embedded in individual rocks or bones, but that doesn’t mean it’s infallible.

Now, a new article is published on Thursday in the magazine Science revealed researchers of the original study have to confess that: These are not chameles.

In fact, they are something completely different.

Identifying fossil animals is a complex undertaking best process. Especially when you are dealing with 99 million year old fossils preserved in amber.

Juan Diego Daza is an assistant professor of biological sciences at Sam Houston State University and lead author of the 201

6 study. Scientific advance, Daza and his colleagues reported the discovery of dozens of amber-coated fossils from Myanmar dating back to the Middle Cretaceous period.

“Amber is great for trapping small and elusive animals that you wouldn’t find in other fossilized methods,” Daza said. Inverse. “These animals are so small that the likelihood of them being fossilized by other means – for example, normal hard rock fossils – will be very difficult.”

Photos of fossils from the 2016 newspaper.Daza et al (2016)

Amber is also great for trapping other objects that can provide important clues about these animals’ environments – a grain of sand can reveal a beach habitat, for example, while a fly Can suggest fossil animals’ favorite prey.

But the amber is not the snowball. With its deep, changeable orange color and round shape, amber visually distorts what it contains, making it difficult to identify the details of the animals preserved inside. This is even more difficult when handling juvenile specimens, whose bones will not fully develop when they are trapped.

Cut from 2016. Daza and his colleagues are fairly confident that one of the fossils they found – with a nifty tongue – was an ancient chameleon.

Turns out they were wrong.

Forensic fossils – After publishing in 2016, Daza received a call. Another paleontologist, Susan Evans, has some bad (and good) news: The Daza chameleon is in fact a long-extinct amphibian – albanerpetontids, also known by the cute nickname “albies”.

“The albanerpetontids – They are very unusual amphibians, “says Daza. In a way, the body shape is similar to salamanders in the sense that they have four legs. And they have tails – something that other amphibians live on today [don’t have]. “

“Maybe, one day, someone will spot it in a secluded forest in Borneo or somewhere in the world that no one has ever passed.”

With their claws and scales, albies are said to closely resemble a reptile – like a chameleon. But it turns out that albies also have another thing in common with modern reptiles – that is the strange tongue.

Albanerpetontids shares with the chameleon a single bone between the jaws, essentially the bone that supports the tongue. And that’s very similar in both groups, ”says Daza.

To complicate matters, at the time, the majority of albie fossils were found in Europe or North America, not Asia. Daza wasn’t sure what they found, until he got an unexpected break in 2018.

At the end of 2018, Daza received an email from gems Adolf Peretti that would change everything. Peretti has 60 vertebrate fossils from Myanmar, and Daza asked Peretti to CT scan the entire collection to better identify key details in the fossil.

The results turned out to be of benefit to Daza – Peretti found a well-preserved adult albie specimen in his collection.

Comparing the offspring in their study to Peretti’s adult specimen allowed Daza and his colleagues to update the 2016 study.

They identified these fossils from Myanmar as belonging to a new genus and species: Yaksha perettii, named not only for Peretti, but also for Hindu souls, or yaks, related to nature.

In other words, Daza and his colleagues may have been of the wrong species. But what they discovered is perhaps the oldest example of a launcher blade discovered in the wild.

The scans revealed albie’s skull structure in detail.Daza et al, Science (2020)

Waiting game – According to Daza, the albie’s fast-moving “ballistic” tongue means it could be a “sit and wait hunter”, according to Daza.

“They remain stable until the prey comes close and when the prey is within reach of their tongue, they quickly shoot at the tongue. And, normally, the end of the tongue is stuck. It reaches their mouth, “he said.

But why does a chameleon, a reptile, have the same characteristics as an albie, an amphibian? It’s all about evolution converging, Daza said.

“It’s a process in biology that we call convergence. Basically, it’s when two or more groups develop similar traits to perform the same function,” he explained.

“This is the first amphibian of this group so well preserved, so it gave us a better understanding of anatomy and helped us do something almost impossible to do with many fossils. : Analyzing the bones one by one, Daza adds.

Researchers also better understand the growth of organisms. For example, it seems that albies do not necessarily have a tadpole-like larval stage before it becomes an adult frog.

Research shows that the Albies shares a slingshot-like blade similar to modern chameleon.Daza et al, Science (2020)

“If these are juveniles, and this is an adult, we suspect that when they hatch from the eggs, they are almost in shape,” Daza said.

The Albies had a long dynasty; This species existed for at least 165 million years and is thought to have gone extinct just two million years ago, leaving no living descendants today.

But is there a small possibility that the albie species may not be truly extinct, but really out there waiting to be found? It’s really Not that is a distant idea.

“We don’t know,” Daza said. Maybe, one day, someone will spot one in an isolated forest in Borneo or somewhere in the world no one has been.

Abstract: The Albanerpetontids are tiny, mysterious fossil amphibians with a distinct set of characteristics, including specialized scales and jaw and neck joints. Here we describe a new genus and species of albanerpetontid, represented by three-dimensional and fully articulated specimens preserved in amber. These specimens preserve the skeleton and soft tissues, including an elongated middle hyoid element, the tip of the part still embedded in a distal tongue pad. This arrangement is very similar to the long and rapidly protruding tongue of a chameleon. Consequently, our results suggest that albanerpetontids are sit-and-wait, sit-and-go ballistic-blade eaters, extending this particular diet record by about 100 million years.


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