Tagged: Science

These poor creatures suffered from dandruff 125 million years before Head And Shoulders was invented

These days, if you notice a bit of dandruff on your shoulder you just stop by the drug store and grab some specialized shampoo, but 125 million years ago the birds and feathered dinosaurs just had to deal with it. A new study published in Nature Communications has revealed that the ancient creatures shed their skin in small bits rather than in large chunks like most present day reptiles. According to the researchers, this new discovery also reveals how well the animals could fly.

The scientists, who were originally studying the fossilized feathers of the dinosaurs, discovered the presence of tiny “white blobs” which they ultimately determined to be dandruff. The skin flakes are exactly the same as those shed by modern day animals, including humans.

Researchers have long questioned how feathered dinosaurs shed their skin, as it would have been rather inconvenient for them to shed it all in one piece as modern reptiles do. This new discovery suggests that shedding it in tiny flakes evolved alongside the emergence of feathers, right around the middle of the Jurassic Period.

“There was a burst of evolution of feathered dinosaurs and birds at this time, and it’s exciting to see evidence that the skin of early birds and dinosaurs was evolving rapidly in response to bearing feathers,” Dr Maria McNamara of University College Cork, Ireland, and lead author of the work, explains. “The fossil cells are preserved with incredible detail – right down to the level of nanoscale keratin fibrils. What’s remarkable is that the fossil dandruff is almost identical to that in modern birds – even the spiral twisting of individual fibres is still visible.”

The dinosaur fossils that were studied appeared to match up with those from ancient birds at the time, with dandruff being present in both cases. However, there was a key difference between the fossilized skin flakes and those from modern birds.

The skin cells of the fossils were largely devoid of the fat that is present in the shedded skin of modern birds, which the team believes is a sign that the creatures never got as warm as modern day birds do. They suggest that this is because the ancient feathered dinosaurs never flew for long periods, or were perhaps completely flightless.

These were the only birds that survived the dinosaur-killing asteroid

When the asteroid that struck the Earth in Chicxulub, Mexico, slammed into the surface some 66 million years ago it made life incredibly difficult for just about every living creature on the planet. It caused massive swings in temperature, and shrouded the Earth in a cloud of darkness which killed off plant life on a massive scale. Now, a new study into the effect the asteroid impact had on bird life is suggesting that the only birds to survive the ordeal were actually ground-dwelling species, but why was that the case?

According to the study, which was published in Current Biology, the diversity of the bird species that survived the impact and immediate aftermath was quite narrow. By studying bird fossils from the period prior to the impact and contrasting that with post-impact fossils, the researchers determined that ground-dwelling birds were the only ones who managed to tough it out, and they think they know why.

Thanks to foliage fossils from the time, scientists know that the asteroid sparked massive fires that wiped out huge sections of forest. The deforestation was so dramatic that it prevented birds from nesting as they normally would. In the centuries following the impact, ferns dominated North America, and tree-dwelling bird species simply couldn’t adjust in time. Ground-dwelling, quail-like birds on the other hand were better equipped to deal with this new landscape.

The researchers say that only a handful of modern bird types were actually around prior to the asteroid’s arrival, including the ancient ancestors of chickens and ducks. Gathering their food from the ground rather than finding it by air, these primitive birds were able to hang on against all odds.

However, as Science magazine points out, some researchers aren’t so ready to accept these dramatic findings. Some have suggested that the scientists behind the work are trying to draw broad conclusions from a smattering of evidence. “It’s a debate that’s been going on for decades,” Joel Cracraft of the American Museum of Natural History in New York City notes. “I don’t think it’s going to end any time soon.”