Cork (Ireland), Strong but light, beautiful and precisely structured, feathers are the most complex skin appendages that have ever evolved in vertebrates.
Despite the fact that humans have been playing with feathers since prehistoric times, there is still a lot we don't understand about them.
Our new study found that some of the first feathered animals also had skull skin like that of reptiles. Following the introduction of the first feathered dinosaur, Sinosauropteryx prima, in 1996, a series of discoveries led to a more An interesting picture has been painted.
We now know that many dinosaurs and their flying cousins, the pterosaurs, had wings.In the past, feathers came in a wide variety of shapes – for example, ribbon-like feathers with extended ends were found in dinosaurs and extinct birds, but not in modern birds. Only a few ancient types of feathers have been inherited by birds today.
Paleobiologists have also learned that early feathers were not designed for flight. Early feather fossils had simple structures and sparse distribution on their bodies, so they may have been for display or tactile sensing. Pterosaur fossils suggest that they may have played a role in thermoregulation and colo patterning.As fascinating as these fossils are, ancient feathers tell only part of the story of feather evolution. The rest of the action took place in the skin.
Nowadays the skin of birds is soft and evolved to support, control, growth and pigmentation of feathers, unlike the scaly skin of reptiles.
Dinosaur skin fossils are more common than you think. However, to date, only a handful of dinosaur skin fossils have been examined at the microscopic level.These studies, for example a 2018 study of four fossils with preserved skin, showed that the skin of early birds and their close dinosaur relatives (the coelurosaurs) was already very similar to the skin of today's birds. Bird-like skis evolved before the arrival of bird-like dinosaurs.
So to understand how bird-like skin evolved, we need to study the dinosaurs that emerged earlier down the evolutionary tree.
Our study shows that at least some feathered dinosaurs had scaly skin, like reptiles today. The evidence comes from a new specimen of Psittacosaurus, a horned dinosaur with hair-like feathers on its tail.Psittacosaurus lived in the early Cretaceous period (about 130 million years ago), but its descendant, the ornithischian dinosaurs, diverged from other dinosaurs much earlier, in the Triassic period (about 240 million years ago).
In the new specimen, the soft tissues are hidden to the naked eye. However, under ultraviolet light, the scaly skin reveals itself in an orange-yellow glow. Skin is preserved on the torso and limbs which are the parts of the body that do not have feathers.
These bright colors are from the silica minerals that are responsible for preserving the fossilized skin.During fossilization, silica-rich fluids penetrate the skin before it decomposes, replicating the structure of the skin in incredible detail. Subtle physical features are preserved, including the epidermis, ski cells, and skin pigments called melanosomes. The fossil skin cells have many similarities with modern reptile skin cells. The cells are similar in size and shape and have fused cell boundaries – a feature known only in modern reptiles.
The distribution of fossilized skin pigments is similar to that of modern crocodile scales.However, the fossil's skin appears to be relatively thin by reptile standards. This suggests that the structure of the fossil scales in Psittacosaurus was also similar to that of reptile scales.
Reptile scales are hard and tough because they are rich in a type of skin-forming protein, hard corneous beta protein. In contrast, the skin of birds is made of a different protein type, keratin, which is the major structural material in hair, nails, claws, hooves, and our outer skin. To provide physical protection, the thin, naked skin of Psittacosaurus was hard. Reptilian-style corneous would be composed of beta proteins.Without feathers for protection the soft bird-style skin would have been too fragile.
Collectively, the new fossil evidence indicates that Psittacosaurus had reptile-style skin in areas where it did not have feathers. The tail, which preserves feathers in some specimens, unfortunately did not preserve feathers or skin in our specimen.
However, tail feathers on other specimens suggest that some bird-like ski features may have already evolved to hold the feathers in place. So our discovery shows that early feathered animals had a variety of skin types, with only feathered areas of the body having bird-like skin, and the rest of the skin being scaly like modern reptiles.This regional evolution would have ensured that the skin would protect the anima against abrasion, dehydration, and pathogens.
what next?
The next knowledge gap for scientists to explore is the evolutionary transition from the reptile-style skin of Psittacosaurus to the skin of other more heavily feathered dinosaurs and early birds. We also need more experiments to study the process of fossilization. We don't understand a lot about how soft tissue fossils form, which means it's difficult to tell which skin features in a fossil are genuine biologic features and which are simply artifacts of fossilization. ,
Over the past 30 years, the fossil record has puzzled scientists regarding the evolution of feathers.Future discoveries of fossil feathers may help us understand how dinosaurs and their relatives evolved flight, warm-blooded metabolism, and how they communicated with each other. (talk) PYPY
Despite the fact that humans have been playing with feathers since prehistoric times, there is still a lot we don't understand about them.
Our new study found that some of the first feathered animals also had skull skin like that of reptiles. Following the introduction of the first feathered dinosaur, Sinosauropteryx prima, in 1996, a series of discoveries led to a more An interesting picture has been painted.
We now know that many dinosaurs and their flying cousins, the pterosaurs, had wings.In the past, feathers came in a wide variety of shapes – for example, ribbon-like feathers with extended ends were found in dinosaurs and extinct birds, but not in modern birds. Only a few ancient types of feathers have been inherited by birds today.
Paleobiologists have also learned that early feathers were not designed for flight. Early feather fossils had simple structures and sparse distribution on their bodies, so they may have been for display or tactile sensing. Pterosaur fossils suggest that they may have played a role in thermoregulation and colo patterning.As fascinating as these fossils are, ancient feathers tell only part of the story of feather evolution. The rest of the action took place in the skin.
Nowadays the skin of birds is soft and evolved to support, control, growth and pigmentation of feathers, unlike the scaly skin of reptiles.
Dinosaur skin fossils are more common than you think. However, to date, only a handful of dinosaur skin fossils have been examined at the microscopic level.These studies, for example a 2018 study of four fossils with preserved skin, showed that the skin of early birds and their close dinosaur relatives (the coelurosaurs) was already very similar to the skin of today's birds. Bird-like skis evolved before the arrival of bird-like dinosaurs.
So to understand how bird-like skin evolved, we need to study the dinosaurs that emerged earlier down the evolutionary tree.
Our study shows that at least some feathered dinosaurs had scaly skin, like reptiles today. The evidence comes from a new specimen of Psittacosaurus, a horned dinosaur with hair-like feathers on its tail.Psittacosaurus lived in the early Cretaceous period (about 130 million years ago), but its descendant, the ornithischian dinosaurs, diverged from other dinosaurs much earlier, in the Triassic period (about 240 million years ago).
In the new specimen, the soft tissues are hidden to the naked eye. However, under ultraviolet light, the scaly skin reveals itself in an orange-yellow glow. Skin is preserved on the torso and limbs which are the parts of the body that do not have feathers.
These bright colors are from the silica minerals that are responsible for preserving the fossilized skin.During fossilization, silica-rich fluids penetrate the skin before it decomposes, replicating the structure of the skin in incredible detail. Subtle physical features are preserved, including the epidermis, ski cells, and skin pigments called melanosomes. The fossil skin cells have many similarities with modern reptile skin cells. The cells are similar in size and shape and have fused cell boundaries – a feature known only in modern reptiles.
The distribution of fossilized skin pigments is similar to that of modern crocodile scales.However, the fossil's skin appears to be relatively thin by reptile standards. This suggests that the structure of the fossil scales in Psittacosaurus was also similar to that of reptile scales.
Reptile scales are hard and tough because they are rich in a type of skin-forming protein, hard corneous beta protein. In contrast, the skin of birds is made of a different protein type, keratin, which is the major structural material in hair, nails, claws, hooves, and our outer skin. To provide physical protection, the thin, naked skin of Psittacosaurus was hard. Reptilian-style corneous would be composed of beta proteins.Without feathers for protection the soft bird-style skin would have been too fragile.
Collectively, the new fossil evidence indicates that Psittacosaurus had reptile-style skin in areas where it did not have feathers. The tail, which preserves feathers in some specimens, unfortunately did not preserve feathers or skin in our specimen.
However, tail feathers on other specimens suggest that some bird-like ski features may have already evolved to hold the feathers in place. So our discovery shows that early feathered animals had a variety of skin types, with only feathered areas of the body having bird-like skin, and the rest of the skin being scaly like modern reptiles.This regional evolution would have ensured that the skin would protect the anima against abrasion, dehydration, and pathogens.
what next?
The next knowledge gap for scientists to explore is the evolutionary transition from the reptile-style skin of Psittacosaurus to the skin of other more heavily feathered dinosaurs and early birds. We also need more experiments to study the process of fossilization. We don't understand a lot about how soft tissue fossils form, which means it's difficult to tell which skin features in a fossil are genuine biologic features and which are simply artifacts of fossilization. ,
Over the past 30 years, the fossil record has puzzled scientists regarding the evolution of feathers.Future discoveries of fossil feathers may help us understand how dinosaurs and their relatives evolved flight, warm-blooded metabolism, and how they communicated with each other. (talk) PYPY
