Dinosaur fossils •

Seeds Saved Birds from the Dinosaur Extinction

April 22, 2016 By Deborah Nielsen Leave a Comment

The fossils of several feathered non-avian Maniraptoran dinosaurs

While the reason behind the extinction of the dinosaurs is a generally known fact, it was only in a recent study that we found out that the giant reptiles that ruled out planet in the past had been on the decline for some fifty million years before they went extinct.

This had to do with more than a single factor, as volcanic eruptions, the separation of the continents, and on-going climate change caused by billions of tons of carbon dioxide being pumped into the atmosphere all contributed to the dinosaurs’ slow but certain decline. But that’s not to say that had the asteroid not hit the dinosaurs would have still been extinct.

Oh no, they would likely have still been around today, only in a much different form than the one to which we are used. This is even proven by the fact that there are still members of the theropod class of dinosaurs still alive today. And yes, I am talking about birds.

But seeing as they evolved from dinosaurs that were alive sixty-six million years ago, how exactly did they manage to evolve? Well, according to a recent study from the Universities of Toronto and Alberta, seeds saved birds from the dinosaur extinction. Well, not birds as we know them today, but maniraptoran dinosaurs, a clave of small carnivorous theropods that largely resembled today’s birds.

So if the modern day birds’ ancestors were carnivorous and they were alive when the asteroid hit, how is it that we still have birds, and what did seeds have to do with anything? Well, as the climate was changing, as the dinosaurs were dying off, and as the sunlight was covered by a cloud of ash, food was beginning to be very scarce.

While meat was getting rarer and rarer, and plants couldn’t really photosynthesize with no sunlight, one of the very few sources of food remaining were seeds. Buried in the ground and viable for consumption for up to five decades, the dinosaurs that wanted to survive had to adapt to their new conditions.

Of course, larger dinosaurs couldn’t really survive on just seeds, so the smaller, carnivorous, toothed maniraptorans had to combine their meaty diet with plenty of seeds. Over time, they evolved so that they lost their teeth and started eating mostly seeds and other creatures smaller than them, eventually reaching the form of today’s birds.

One of the biggest problems with identifying that particular class of dinosaurs was that their bones were very fragile. So, it’s a very common occurrence for the only fossils encountered by scientists to be the teeth, as they tended to be stronger than the regular bones. This made it quite hard for the team to actually find out when maniraptorans evolved into birds, even if they tried to reverse engineer the process by following the birds’ ancestors instead of the dinosaurs’ descendants.

Image source: Wikimedia

Unique Ancient Fossils Of A ‘Wildebeest’ Unearthed In Kenya

February 5, 2016 By Jason Leathers Leave a Comment

Diagram of a Rusingoryx skull.

The paleontologists are discussing about the unique ancient fossils of a ‘Wildebeest’ unearthed in Kenya. The creature named Rusingoryx has left researchers speechless, as its nasal structure is more like of a dinosaur than that of a mammal.

At first glance, it seems unlikely that a shaggy-maned antelope from the Ice Age could have anything in common with a group a dinosaurs that roamed during the Cretaceous period 145 to 66 million years ago. However, science can be full of surprises.

Rusingoryx atopocranion is the name of the spcies that is related to the modern wildebeest. Below, you can see an image with the wildebeest in its natural habitat:

And here is an artist’s interpretation of Rusingoryx atopocranion:

The experts’ observation is that the newly discovered ‘beast’ shares a bizarre adaptation with a group of hadrosaurs: a hollow, domed ridge of bone along the front of its face called a nasal crest.

This structure was incredibly surprising. To see a hollow nasal crest outside of dinosaurs and in a mammal that lived so recently is very bizarre.

– Ohio University paleontologist Haley O’Brien said.

These fossils of Rusingoryx, about the size of its close cousin the wildebeest, date from about 55,000 to 75,000 years ago. Hadrosaurs with similar nasal structures, Lambeosaurus and Corythosaurus, lived about 75 million years ago.

O’Brien said the structure was an example of ‘convergent evolution‘ in which disparate organisms independently evolve similar features, like the wings of birds, bats and the extinct flying reptiles called pterosaurs, to adapt to similar environments or ecological niches.

About Rusingoryx’s lifestyle, the researchers say that they led a lifestyle similar to hadrosaurs: herbivores both likely traveling in herds. Many scientists think hadrosaurs also used their crests to communicate vocally with one another.

Moreover, the experts say that Rusingoryx’s nasal apparatus may have allowed it to deepen its normal vocal calls into ‘infrasound’ levels other species may not have been able to hear.

In order to come to a conclusion, the researchers examined six adult and juvenile Rusingoryx skulls. The bony crest, laying on the top and front of the skull, was mostly hollow inside. It contained nasal passages that followed the outside of the structure then took an S-shaped pathway down into the soft tissue part of the airway. The nasal passage then sat atop of a pair of large sinuses.

At least 24 Rusingoryx individuals were found at the site. University of Minnesota paleoanthropologist Kirsten Jenkins said butchered bones and stone tools there indicated humans may have caused their deaths. Jenkins said hunters may have driven a herd into the stream for an ambush.

This research was published in the journal Current Biology.

Image Sources: abc.net.au; wikimedia.org; guim.co.uk.

Rukwatitan bisepultus: Titanosaurian Dinosaur Fossils Found in Tanzania

September 9, 2014 By Jason Leathers Leave a Comment

Remnants of Titanosaurian are mostly found in South America. A team of researchers from Ohio University have discovered one more member of the species situated in Tanzania.

Titanosaurians were a diverse group of sauropod dinosaurs who were the last and the biggest family of dinosaurs.

These fossils are found in the Rukwa Rift Basin of southwestern Tanzania. The researchers completed this task in two different field sessions and in both sessions they excavate the area through coal miners. Afterwards, researchers examined these fossils and concluded that they have unearthed a new dinosaur species. Researchers gave this specie a Latin name Rukhwatitan bisepultus which means double buries.

The dinosaur lived nearly 100 million years ago during the time period of the Cretaceous. Although it has forelimb of almost 2 meters, but still it was not the largest sauropod.

Malawisaurus Dixeyi was another titanosaurian that was discovered in a nearby country Malawi. The researchers stated that Malawisaurus is quite similar to the Rukhwatitan bisepultus. Both the dinosaurs are pretty different from each other in terms of appearance.

It is an extremely difficult task to find fossils of dinosaur in Africa because of several reasons. The chief reason is that Africa has not progressed that much which means the fossils are still buried in the contient. The best places for the remains of dinosaurs are hardly found in Africa. The second cause is a bit political because most of the African countries do not offer a safe search environment to the researchers.

Luckily, the fossils of Rukwatitan bisepultus have been hidden twice due to remains which encourages fossilization.

Researchers concluded that the region might have been very separate from other areas because of which animals could have faced mobility restrictions.

Researchers have discovered only four titanosaurians in Africa. On the other hand, in South America, they found 30.

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