A creation that is known for its product T. rex Fossils have now provided the oldest evidence of primates in the fossil record, in which it is claimed to have been largely discovered.
Seagrass and tooth collection found in the Hell’s Creek formation in northeastern Montana are the oldest primary fossils ever found, according to a new research published in the Open Science of the Royal Society.
Dating back to about 65.9 million years ago, these animals lived just 105,000 to 139,000 years after the Cretaceous-Paleogene extinction event, in which an asteroid wiped out most plant species. and animals on Earth. The new paper was co-directed by Gregory Wilson Mantilla of Washington University and Stephen Chester of Brooklyn College and New York City University.
“This is an important study as it records the earliest primates ever found, pushing back the date of the oldest primates to the earliest Paleocene, as well as establishing more diversity too, ”Eric Sargis, a professor of anthropology at Yale University who is not affiliated with the new study, said in an email.
Of course, the age of these fossils is important, as it shows that the ancestors of all primeval, both extinct and extinct, lived in Mesozoic times, especially the Late Cretaceous. . Prior to this discovery, the oldest evidence of stem, or early, primates in the fossil record dates back to the first 300,000 to 500,000 years of the Paleocene (the epoch that followed the Mesozoic).
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The recently discovered teeth and kidneys belong to two different species: P. janisae and P. mckeeveri. Both species belong Purgatorius, the oldest known genus associated with primates. Other members of this group include P. unio and P. ceratops, and are all seen as plesiadapiforms – a gas group of primers that enclose Purgatorius and from which all modern primates such as monkeys, apes (you introduced) and lemurs came.
P. janisae paleontologists already had experience, however P. mckeeveri a newly defined species named in honor of a family that has supported fieldwork in this area. Three teeth with previously unseen markings Purgatorius the scientists let it reveal that a new species had been discovered.
The team studied the extinct creatures by poring over a large collection of fossils at the University of California Museum of Paleontology, which hosts the largest collection of P. janisae fossils. They also had other epoxy feet Purgatorius fossils to work with, as well as augmented 3D models printed from microCT scans. The team also used a technique called “geometric morphometrics” to digitize and compare the properties of fossils with other known species.
“This work was carried out by a large team who brought a unique and critical set of skills to this research, from the geologists who were able to turn the age of these fossils to the geologists who were able to find out how deposit those fossils, ”Mantilla said in an email. “We also could not have done this work without the help of generous colleagues at the museums we worked on. [with] and the landowners in Garfield County Montana who allowed us to work on their land. It was a huge team effort. ”
Scientists still do not know the exact time frame for emergence Purgatorius, but the “fact that there are two species” that emerged so soon after extinction “means that the ancestor was older than both species of offspring,” Mantilla wrote. It is increasingly likely that a plesiadapiform ancestor arose “first in the Late Cretaceous rather than in the Paleocene,” he said, implying that the earliest proto-primates would have been rubbed by the dinosaurs.
As for the precursor to Purgatorius, that remains a mystery. As Mantilla explained, some North American fossil species dating back to the Late Cretaceous are suggested to have ancestry Purgatorius, including the rat Gypsonictops. It is very likely that “we have not yet found the ancestor in the fossil record,” he said.
These tiny mammals were very similar to a squirrel, however Purgatorius, like other plesiadapiform, “shared dental features with other primates,” Sargis said, noting that their teeth were “primate-like, not rodent-like. ”
I asked Chester what makes a primate a primate, and he replied:
This is a big question and a key topic for all researchers studying primate sources. Until we fully understand what makes a primordial primate, it is difficult to know when our primitive ancestors evolved from other mammals. Many prime ministers today have symptoms related to grip, jump, plant-based diet, improved vision, and intelligence. However, we know from the fossil record that not all of these signals developed at the same time. As paleontologists, we can trace this combination of traces to extinct primates from the earliest Eocene about 56 million years ago. But as you move further back in time to the earliest Paleocene around 66 million years ago, it is clear that our earliest private relatives such as Purgatorius had some of these characteristics, but that is not all. Two sets of important features that emerged very early in primary evolution were skeletal features such as grip on hands and feet for life in the trees and dental features such as specific recommendations for eating plant fruits. non-leafy as a fruit. This combination of beaches allowed our earliest friends to separate themselves from their competition just after the dinosaurs became extinct.
A.s the new study shows, Purgatorius they were among the first successful mammals in Paleocene, appearing “shortly after the accident destroyed non-bird dinosaurs,” Mantilla explained. “There were a couple of changes that allowed them to succeed as a result of this tragedy. Firstly, they were arboreal – they spent most of their time up in the trees – and secondly, they had teeth that allowed them to feed on fruit and insects. ”
Apparently these tokens were allowed Purgatorius “Grow and become a key part of the terrestrial ecosystem within a million years of the event,” he said.
Mammals first appeared during the Late Triassic, about 300 million years ago (we’ve been around for a while!). The prime ministers were able to thrive after the extinction of non-bird dinosaurs was a big surprise. Of course, mammals quickly took over once the terrible berries were gone, eradicating the Mammal Age about 10 million years after the Cretaceous-Paleogene extinction event.
After living under the shadow of dinosaurs for hundreds of thousands of years, our time had finally arrived.