Динозавърски новини

[П. Теодосиев]

Преди 10 години Питър Хевс случайно вижда стърчащи кости от скала по протежението на река Олдман в Канада.

Вчера в научното списанието "Current Biology" е публикуван материал, който обяснява, че тези кости принадлежат на почти непокътнатия череп на необичаен динозавър. Непознатият роднина на Трицератопс е първия открит до сега подобен динозавър.

http://nauka.bg/a/%D0%BD%D0%BE%D0%B2-%D1%80%D0%BE%D0%B3%D0%B0%D1%82-%D0%B4%D0%B8%D0%BD%D0%BE%D0%B7%D0%B0%D0%B2%D1%8A%D1%80-%D0%B5-%D0%BE%D1%82%D0%BA%D1%80%D0%B8%D1%82-regaliceratops-peterhewsi

https://www.youtube.com/watch?v=pxP2AYq7Q4E

[Warlord]

Къде са сега ония ентусиасти размахващи динозавърските статуетки от Перу да кажат: Ето! Североамериканските индианци са видели от брачеда на трицератопса как да си украсяват главите, дрехите и стелите!

[kall]

Да, без креационисти е скучно във форума:-)

[Last roman]

дългогодишният спор дали динозаврите са били покрити с пера или люспи в общи линии приключи в полза на класическата визия /че много фриволни спекулации на пернати Тиранозаври и раптори се навъдиха/:

Most Dinosaurs Were Probably Scaly, Not Feathered

Over the past few years, we’ve heard gathering evidence that dinosaurs were not the cold-blooded, scaly-skinned beasts of the past, but fluffy, feathered, and brightly colored. Well, a new study published in Biology Letters seems to suggest that they might have been more right to begin with, and that most dinosaurs probably didn’t have feathers.

By examining the fossil record of dinosaur skin impressions preserved in rock, researchers from the Natural History Museum, London, have concluded that feathers were far less prevalent than previously believed. Whilst they certainly covered many of the carnivorous dinosaurs, such as velociraptors and tyrannosaurus, the suggestion that some of the larger herbivores were also clad in downy feathers is probably wrong.

“Most of our analyses provide no support for the appearance of feathers in the majority of non-avian dinosaurs,” says Professor Paul Barrett, who co-authored the study. “Although many meat-eating dinosaurs were feathered, the majority of other dinosaurs, including the ancestor of all dinosaurs, were probably scaly.”

It’s fairly well accepted that many theropod dinosaurs, the ones that eventually gave rise to birds, were no doubt covered in what are called “protofeathers.” But some recent discoveries of larger herbivores that also appear to be covered in these feather-like filaments have raised the question of whether the last common ancestor to all dinosaurs was also fluffy. Are feathers in dinosaurs the norm rather than the exception?

Well, by looking at which beasts were downy and which weren’t, and then building an evolutionary tree of how they all related to each other, the scientists discovered that it was most likely that the majority of the dinosaurs were covered in scales, and feathers only evolved in the theropods. But what about the few, stray herbivores that seem to have been covered in quills? It’s possible that those odd exceptions were probably experimenting independently.

“As palaeontologists we are at the mercy of available data, which given the interest in the field are ever changing,” explained Nicolàs Campione, another of the researchers. “Our study shows that dinosaurs experimented extensively with their 'outer look' and potentially independently along separate evolutionary lineages. That is what the data allow us to say at present.”

As dinosaur biology is a hotly debated and hugely competitive area of research, the team working on this study suspect there might be a few vocal objections to their finding, but they accept that this is how science works. “This is a hypothesis that can only be tested with the discovery of new fossils with preserved skin or feathers. In particular, we need fossils that fill key locations in the evolutionary tree of dinosaurs,” says Campione.

http://www.iflscience.com/plants-and-animals/most-dinosaurs-were-probably-scaly-not-feathered

[Warlord]

Е да - не трябва да се изпада в крайности. Действително с доказването на перата през динозавърската епоха, започнаха всички да ги кичат с тях. При по-едрите екземпляри са практически ненужни. За Т-рекс-овете преобладаващата теория е, че са се раждали с пера, които с времето са падали.

[Last roman]

Открити са кръвни телца и колаген в динозавърски фосил на 75 млн. г.:

Dinosaur blood cells extracted from 75-million-year-old fossil

Watch the birdy (Image: Moviestore/REX Shutterstock)

Jurassic Park saw dinosaurs brought back to life based on DNA preserved in the gut of a blood-sucking mosquito entombed in amber. Now we have found what appears to be real dinosaur blood inside a bog-standard fossil bone.

"We stumbled on these things completely by chance," says Susannah Maidment of Imperial College London, whose team was trying to study bone fossilisation by cutting out tiny fragments of fossils.

Instead, they found blood-like cells and collagen from 75-million-year-old dinosaur fossils – 10 million years before T. rex appeared.

Although the cells are unlikely to contain DNA, those extracted from better preserved fossils using the same technique may do so, she says.

And even without DNA, soft tissue cells and molecules could help us learn much more about dinosaur physiology and behaviour, the team says. For example, the physical size of blood cells can reveal insights into metabolism, and the possible transition from a cold to warm-blooded existence.

So far, such soft flesh tissues were only ever found in serendipitous fossils preserved in exceptionally rare circumstances, for example, by being frozen in ice or in a dry environment free of microbes that would otherwise break down the flesh, says Maidment.

Blood cells came from this claw (Image: Laurent Mekul)

"But the fossils we looked at were not rare at all," she says. They were ordinary bones collected from the surface at the well-known Dinosaur Park Formation in Canada.

To study fossil bones, the team borrowed a medical research technique based on a focussed ion beam, that is giving clues to how blood vessels become calcified and cause heart attacks. Their intention was to study how natural bone minerals fossilise, and what happens when collagen decays in dinosaur bones.

"This beam works like a knife, with a microscopic robotic arm bearing a needle that enables you to cut out fragments of interest," says Sergio Bertazzo, also of Imperial College London, who co-led the investigation.

Bird-like collagen fibres (Image: Sergio Bertazzo)

Three-dimensional examinations of the blood-like cells under an electron microscope revealed that they had nuclei, so human red blood cells could not have contaminated the sample, because they have no nuclei.

And when Maidment analysed the chemical composition of the red blood cells with a technique called mass spectrometry, the spectrum was surprisingly similar to that of blood taken from a living bird, an emu, adding further evidence to it being from a dinosaur.

Maidment is now hoping to investigate more samples. "We want to understand how this preservation can occur, how far back in time it happens, and what type of rock it happens in," she says.

The discovery was welcomed by John Asara of Harvard Medical School, whose team reported in 2007 finding collagen in a 68-million-year old T. rex and in an 80-million-year old brachylophosaurus fossil. Asara says this field of science has been barely tapped.

"Papers like this do much to advance the field, by showing that fossils are more than 'just rocks', and opening the door to the possibility that materials persist in ancient fossils that were not thought possible only a few years ago," says Mary Schweitzer of North Carolina State University in Raleigh, who reported extracting blood from T. rex in 2009. "[it also] seems to indicate, like our own findings, that this is not necessarily an exceedingly rare occurrence."

http://www.newscientist.com/article/dn27687#.VXnL9bbFwmM

Редактирано Юни 11, 2015 от Last roman

[Last roman]

Криолофозавърът - първият месояден динозавър, живял в Антарктида в началото на Юрският период:

http://www.exploringlifesmysteries.com/cryolophosaurus/

[Р. Теодосиев]

Нов динозавър на 125 милиона години е открит в Китай

http://nauka.bg/a/%D0%9D%D0%BE%D0%B2-%D0%B4%D0%B8%D0%BD%D0%BE%D0%B7%D0%B0%D0%B2%D1%8A%D1%80-%D0%BD%D0%B0-125-%D0%BC%D0%B8%D0%BB%D0%B8%D0%BE%D0%BD%D0%B0-%D0%B3%D0%BE%D0%B4%D0%B8%D0%BD%D0%B8-%D0%B5-%D0%BE%D1%82%D0%BA%D1%80%D0%B8%D1%82-%D0%B2-%D0%9A%D0%B8%D1%82%D0%B0%D0%B9

[Last roman]

Dinosaurs hunted with wide-gaping jaws

How wide can a dinosaur open its mouth? According to a new study, the Jurassic predator allosaurus could swing its jaws down at a terrifyingly wide right angle, opening its maw nearly 80 centimeters to bite massive prey, Reutersreports. The larger Tyrannosaurus rex could open its jaws at nearly the same angle, while a related plant-eating dinosaur had a much smaller gape of 43.5 degrees. The findings—published Tuesday in Royal Society Open Science—are consistent with measurements from modern animals, which show that carnivores tend to open their mouths wider than herbivores. 

[Last roman]

Missing link between dinosaur nests and bird nests

Analyses of fossil eggshells suggest that duck-billed dinosaurs (depicted at left) buried their eggs in mounds of vegetation like today’s crocodiles, whereas evolutionarily advanced, more birdlike dinosaurs such as oviraptorids (right) incubated their eggs in an open nest.

The links between dinosaurs and birds keep getting stronger: skeletal structures, feathers—and now nests. Whereas some dinosaurs buried their eggs crocodile-style, a new analysis suggests that other dinosaurs built open nests on the ground, foreshadowing the nests of birds.

Interpreting the fossil record is always tough, but analyzing trace fossils such as nests is especially daunting. Those structures, and the materials used to make them, usually aren’t preserved, says Darla Zelenitsky, a paleobiologist at the University of Calgary in Canada. When paleontologists do find a nestlike structure that includes material such as sticks or other vegetation, the question arises: Was this stuff part of the original nest, or just carried there with the sediment that buried the nest and helped preserve it?

To gain insight into dinosaur nesting habits, Zelenitsky and her colleagues studied the most durable parts of nests—the eggs themselves. (Being largely made of the mineral calcium carbonate, they’ve got a head start on fossilization and are sometimes incredibly well preserved.) In particular, the team looked at the size and arrangement of small pores in the ancient shells, because those details are telling in modern creatures.

A nest of fossilized eggs from an oviraptorid dinosaur of the Late Cretaceous period.

In crocodiles’ buried nests, the heat needed to incubate the eggs comes from decomposition of overlying organic matter or the sunlight absorbed by the soil. Plus, in buried nests airflow is somewhat limited, thus requiring eggs to be relatively porous to help increase the flow of oxygen into and carbon dioxide out of the eggs. But birds that brood in open nests can get by laying eggs with fewer or smaller pores.

So the team compared the porosity of eggshells from 29 species of dinosaurs (including large, long-necked herbivores called sauropods; bipedal meat-eaters called theropods; and duck-billed dinosaurs) with that of shells from 127 living species of birds and crocodiles.

Most of the dinosaur eggs were highly porous, suggesting that they buried their eggs to incubate them, the researchers report online today in PLOS ONE. But some of the dinosaur species in one group—a subset of well-evolved theropods considered to be the closest relatives of modern-day birds—laid low-porosity eggs, which suggests they incubated their eggs in open nests.

“This is a well done paper; the results make a lot of sense,” says Luis Chiappe, a vertebrate paleontologist at the Natural History Museum of Los Angeles County in California. The findings, he says, line up other studies suggesting that some birdlike dinosaurs were warm-blooded, which would have enabled them to incubate eggs in an open nest rather than depend on rotting vegetation or sunlight. Chiappe adds that the trend toward open nests could have allowed some dinosaurs to take another step toward birdlike nesting by moving their nests into the trees.

But considering only two types of nests—open versus buried—may be too simplistic, suggests Anthony Martin, a paleontologist at Emory University in Atlanta. Some dinosaurs—like a few of today’s birds—may have nested in burrows, which could have offered the stable temperature and protection from predators of a buried nest but resulted in low-porosity shells. Also, covered nests come in different types: Loose vegetation piled atop a buried nest can have a lot of airflow through it, allowing eggs to have relatively small pores, whereas eggs buried in soil or similar materials might not breathe as well and thus require larger pores, he notes. Nevertheless, Martin adds, the team’s study “is a good first start toward answering the question about what early dinosaur nests looked like.” 

http://news.sciencemag.org/paleontology/2015/11/missing-link-between-dinosaur-nests-and-bird-nests?utm_source=facebook&utm_medium=social&utm_campaign=facebook

 

[Last roman]

Jurassic island:

http://www.bbc.com/earth/bespoke/story/journey-to-jurassic-island/index.html

[Р. Теодосиев]

Следи от вкаменелости на динозаври ни дават възможност да вникнем в живота на праисторическите гиганти

Новооткрита колекция от редки находки на динозаври помага на учените да хвърлят светлина върху някои от най-големите животни, които са живели на сушата.

Стотици следи от стъпки и отпечатъци, направени от растителнояден „гущер” преди около 170 милиона години са били открити на остров Скай в Шотландия.

Откритието – което е най-големият динозавър, е направено в Шотландия и помага на учените да запълнят важна празнина от еволюцията на огромните животни, които са били най-големите сред динозаврите.

Учени от университета в Единбург, идентифицирали следите в слоеве от скали, които са били в дъното на плитка лагуна със солена вода, когато са направени отпечатъците.

Чрез анализиране на структурата на отпечатъците, екипът установява, че става въпрос за динозаври, които са били по-ранни, далечни роднини на по-добре познатите видове, като например Brontosaurus и Diplodocus. Динозаврите в Скай вероятно са достигали до най-малко 15 метра дължина и са тежали над 10 тона.

Отпечатъците – най-големият от които е с диаметър 70 см – са първата следа от тези, които ще бъдат намерени в Шотландия. Досега единственото доказателство, че вида е живял в този район идва от малък брой костите и зъбите фрагменти.

Вкаменелости от периода Юра са изключително редки, и остров Скай е едно от малкото места в света, където те могат да бъдат намерени.

Цялата статия: http://nauka.bg/a/

[Last roman]

Динозаврите еволюирали по-бързо, отколкото се е смятало досега:

Dinosaurs evolved much faster than previously thought

Early relatives of dinosaurs called dinosauromorphs (two creatures shown at right) as well as early cousins of mammals (at left) lived in what is now South America about 235 million years ago.

Dinosaurs evolved from their smaller ancestors in just a few million years and not the 10 million years or more scientists had suspected, according to a new study. The work, based on radioactive dating of rocks sandwiching the earliest fossils of those predecessors, suggests that paleontologists have long misjudged the overall pace of dinosaur evolution.

The fossils analyzed in the new study are among the earliest of a broad group of creatures called dinosauromorphs. That group includes all dinosaurs but also includes their earlier predecessors and their subsequent kin, which had the same general body plan but didn’t have distinctive anatomical features in their hip bones that all true dinosaurs shared.

The earliest known dinosauromorphs lived in parts of the ancient supercontinent Pangaea that are now South America and southern Africa. But those fossils aren’t well-dated. Scientists have estimated the arrival of these early members of the dinosaur family tree by trying to match them up to the putative ages of the fossils of reptiles and other animals appearing in the same rocks. That technique is known as biostratigraphy, and it is typically much less accurate than methods such as uranium-lead dating. “There’s a lot of uncertainty in the ages of those rocks,” says Kenneth Angielczyk, a vertebrate paleontologist at the Field Museum of Natural History in Chicago, Illinois, who wasn’t involved in the new study. That’s particularly true because the rocks from southern regions of Pangaea don’t include occasional layers of marine sediments, which offer a different range of creatures to help correlate ages.

Now, Randall Irmis, a vertebrate paleontologist at the University of Utah in Salt Lake City and his colleagues have used uranium-lead radioactive dating to estimate the age of what are suspected to be the earliest dinosauromorphs. Unearthed from rocks in northwestern Argentina, the creatures were previously thought to have lived anywhere between 237 million and 247 million years ago. But uranium-lead dating, in which researchers estimate the age of a rock by comparing its concentrations of radioactive uranium and the lead it decays into, tells a different story.

A younger volcanic deposit lying in the rock above these fossils includes zircons, tiny bits of silicate mineral that often contain trace amounts of uranium. Those zircons crystallized about 234 million years ago, the team’s analyses suggest. And older sediments below the fossils contain zircons that crystallized about 236 million years ago, the researchers report online today in the Proceedings of the National Academy of Sciences. So, the fossilized creatures must have lived between those two dates. That means that the earliest known dinomorphs lived anywhere from 3 million to 5 million years later (or even more) than previously estimated, Irmis says. That, in turn, means that dinosaurs must have evolved faster than previously thought.

By shifting the earliest dinosauromorphs' first appearance toward the present, the findings suggest that they appeared only after ecosystems had largely recovered from the end-of-the-Permian mass extinctions, says Paul Olsen, a paleontologist at Columbia University’s Lamont-Doherty Earth Observatory in Palisades, New York. Those die-offs, which occurred about 252 million years ago, killed off more than 90% of all species on Earth, and their ecological effects were long-lasting.

The shorter time needed for true dinosaurs to evolve suggests that the shift in ecosystems associated with their appearance was smoother than previously thought. The earliest dinosaurs and their predecessors, the earliest dinosauromorphs, “were only slightly different players,” says Sterling Nesbitt, a vertebrate paleontologist at Virginia Polytechnic Institute and State University in Blacksburg. The creatures in those two groups looked and behaved pretty much the same, but “dinosaurs were slightly larger overall,” he notes. So, an overall mix of creatures dominated by early dinosaurs didn’t really look that much different from earlier ones where dinosauromorphs were predominant, he notes.

The question now, Nesbitt says, is why early dinosauromorphs eventually faded away while dinosaurs as a whole rose to dominance for almost 170 million years.

http://news.sciencemag.org/paleontology/2015/12/dinosaurs-evolved-much-faster-previously-thought?utm_source=general_public&utm_medium=facebook-text&utm_campaign=evolvedinoFB-1271

[Last roman]

нов орнитопод с 'платно' на гърба, открит в Испания:

Новият динозавър - Morelladon beltrani, живял на Иберийския полуостров преди 125 млн. г., е бил висок около 2.5 метра и дълъг около 6 метра. Характерна негова черта били изпъкналите прешлени на гръбначния стълб, покрити с кожа, като вероятно този израстък е служел за регулиране на телесната температура.

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0144167

[Last roman]

Динозаврите май са имали любовни танци:

Dinosaurs may have danced like birds to woo mates

Male dinos might have competed in dirty dancing contests to win the hearts of females

Did meat-eating dinosaurs like Tyrannosaurus rex do a chicken dance to woo their mates? That’s the implication of a new study, which points to fossilized foot scrapes as evidence that a variety of dinosaurs pranced like parrots and puffins to impress the opposite sex. The finding adds further evidence that ancient dinos shared many of the same behaviors as their modern bird relatives.

“Most or perhaps all of the behaviors present in birds today originated in nonbird dinosaurs,” says Darren Naish, a paleontologist at the University of Southampton in the United Kingdom. “If these scrape marks are really what the authors say they are, this study is pretty compelling support for that contention.”

The scrape marks were uncovered at four sites in Colorado by a team led by Martin Lockley, a paleontologist at the University of Colorado, Denver. Three of the sites are in western Colorado, and one is in the east of the state. All contain sediments of the Dakota Sandstone, a geological formation laid down during the Cretaceous period, which stretched from about 145 million to 66 million years ago. The largest of the four sites, in western Colorado, features some 60 scrapes on a sandstone surface measuring about 50 meters long and 15 meters wide. Most of the scrapes are made up of parallel double gouges in the ground, and some also include the clear outlines of three-toed footprints.

From their size and shape, Lockley thinks the traces were probably made by the meat-eating dinosaur Acrocanthosaurus, which lived about 110 million years ago and was one of the largest carnivores in the area at that time. It weighed as much as 6 metric tons, was up to 11 meters long, and sported a long, narrow skull and bony spines poking up from its vertebrae that probably supported a ridge made of tough muscle.

Writing online today in Scientific Reports, the team argues that the scrapes closely resemble those made by ground nesting birds—such as the Atlantic puffin and some species of plovers and parrots—that engage in “very energetic” courtship displays, which include lots of prancing around and scratching the ground.

“Birds seem to get in a frenzy of prenuptial, premating activity,” Lockley says, adding that the “bird literature actually speaks about peaks of emotional activity. It seems that [carnivorous] dinosaurs did the same.”

 

 

 

M. LOCKLEY

 

 

 

Co-authors Martin Lockley (right) and Ken Cart pose next to scrape marks made by meat-eating dinosaurs.

 

To be sure that its interpretation was sound, the team considered and rejected several other explanations. These included the possibility that the scrape marks were made while dinos were digging for food or water, while marking territory, or even while building nests or gathering in colonies. Only the courtship display hypothesis, the researchers concluded, was consistent with all of the features of the scrape marks, such as their abundance, spacing, and density on the ground.

The traces “do not seem connected to nest building, burrowmaking, or finding food and water,” agrees Anthony Martin, a paleontologist at Emory University in Atlanta. “So wooing traces are a good explanation, especially when compared to modern bird traces. They also tell us how much energy dinosaurs put into wooing a potential mate, which they apparently did by feeling the earth move under their feet.”

Naish adds that although he was “initially extremely skeptical” when he first started reading the paper, he now thinks that “they may well be on to something.” But he says he still wonders “if there’s an explanation the authors might have missed.”

For example, the scrape marks could have been made when meat-eating predators, such as the mighty Acrocanthosaurus, scraped their powerful hind legs on the ground to make noise and warn other males—of either the same or a different species—to stay away, says Timothy Isles, a paleobiologist at the University of Portsmouth in the United Kingdom. An even bigger problem, he says, is that competitive displays by male birds seeking to mate with females are “only observed in a small number of species around the world.” That makes it less likely, he says, that the behavior was “widespread and ubiquitous” in their extinct dinosaur ancestors.

http://news.sciencemag.org/plants-animals/2016/01/dinosaurs-may-have-danced-birds-woo-mates?utm_source=newsfromscience&utm_medium=facebook-text&utm_campaign=woomates-1759

[Warlord]

Все повече общи с птиците черти се установяват. Интересно на Аргентинозавъра примерно любовния танц до колко по Рихтер го е докарвал

[Last roman]

е, предполагам, че са си търкали шиите и са се подпирали, подобно на днешните едри бозайници.  

А като се има предвид, че птиците са еволюирали дребни динозаври - ми нормално е да са усвоили и техните навици.

[Р. Теодосиев]

Динозаврите може да са танцували като птиците, за да привлекат партньори

Дали месоядните динозаври като тиранозавър рекс са танцували, за да привлекат партньори? Това ще е изводът от ново изследване, което използва фосилизирани отпечатъци като свидетелство за разнообразието от динозаври лудували като папагали и пуфини, за да впечатлят противоположния пол. 

“Повечето или всичките действията на сегашните птици произхождат от динозаврите”казва Дарен Найш, палеонтолог от Университетът на Саутхемптън, Великобритания. “Ако тези повърхностни следи са наистина това, което авторите казват, то това изследване подкрепя тази теза.”

Цялата новина: http://nauka.bg/a/

[Last roman]

откриха най-ранния Юрски динозавър:

This may be the world’s oldest Jurassic dinosaur fossil

 

It could be the long-lost ancestor of the dinosaurs from Jurassic Park. A fossil discovered in the UK is thought to be the oldest Jurassic dinosaur ever found and is one of the most complete specimens from the time period.

The well-preserved remains of a juvenile dinosaur were found at Lavernock Point near Cardiff, Wales, a location that exposes rocks spanning from the late Triassic to the early Jurassic.

The fossil came from rocks that lie right in between these two eras, but subsequent analysis showed the specimen was from the early Jurassic.

“Only a few handfuls of specimens worldwide come from this time and most of them are only fragments,” says Steven Vidovic from the University of Portsmouth in the UK, a member of the team that investigated the fossil.

The early Jurassic is a critical time in the evolutionary history of dinosaurs. An extinction event in the late Triassic wiped out many plants and animals, but not dinosaurs.

The species that crossed over into the Jurassic are thought to hold clues as to how they diversified into the many species that existed in the middle Jurassic, some of which are the ancestors of birds.

Peculiar features
The specimen classifies as a new genus and species of neotheropod. It has been named Dracoraptor hanigani, its genus name referring to the national symbol of Wales – the dragon.

It has peculiar features, like short arms but hands as big as its forearms, and is estimated to have been about two metres long, although the specimen might have been a juvenile. Its teeth suggest that it was a carnivore.

Serrations-on-the-toothAmgueddfa Cymru/National Museum of Wales

Vidovic thinks the fact it has a similar overall appearance to many later dinosaurs indicates that it set this body plan. “We are seeing what it had in common with everything after it,” he says. “It was a forerunner.”

The skeleton is about 40 per cent complete. Vidovic says it actually represents about 80 per cent of the animal because dinosaurs are symmetrical.

Its remarkable condition should allow for a more detailed analysis in the future.

Dino tales
“Dracoraptor is one of the best preserved meat-eating dinosaurs from the early part of the Jurassic Period – not only in Europe, but globally,” says Paul Barrett, of the Natural History Museum in London, UK. “Its discovery will probably have much to tell us about dinosaur distributions in the wake of the major extinctions.”

He adds that our knowledge of early dinosaurs is based mainly on sites in South America, Africa and Asia, so the discovery of this species in Wales is exciting. “Especially as Wales has not previously been fertile ground for dinosaur hunters.”

Hand-bonesAmgueddfa Cymru/National Museum of Wales
There is still some debate about whether Dracoraptor dates from the late Triassic or early Jurassic. This is because there weren’t enough fossils of known species found above and below it that could help to narrow down the chronology.

“There is reasonable argument that it is definitely post-extinction, and probably earliest Jurassic,” says Michael Benton, a palaeontologist at the University of Bristol, UK. “Dinosaurs from this time are pretty rare worldwide.”

Journal reference: PLoS ONE, DOI: 10.1371/journal.pone.0145713

[Last roman]

Батманът на динозаврите е открит от китайски учени

Китайските учени са реконструирали един странно изглеждащ, летящ, с размерите на гълъб, динозавър с ципести, подобни на прилет крила, чиито останки са намерени от фермер от провинция Хъбей

По предварителни данни, възрастта на находката е около 160 милиона години - в края на периода Юра, разказва Live Science. 

Китайските палеонтолози са дали име на динозавъра Yi Qi - "Странно крило". Учените смятат, че принадлежи към месоядните тероподи, в рамките на които има малка група от птици scansoriopterygids. Летящият динозавър е тежал около 380грама.

На изследователите са направили впечатление необичайно дългите кости на животното, продължаващи от предните крайници и свързани с мембрана, подобна на ципата на летящите катерици и прилепите. Динозавърът Yi Qi е имал и пера, но не ги е използвал по време на полет.

Като цяло не е можел да лети особено добре. За разлика от други динозаври, пернатият дребосък е може би неуспешен експеримент в началото на еволюцията на птиците, казват изследователите.

Dinostar Co. Ltd

"Съществото е първият известен динозавър с ципести крила", каза Xing Xu, палеонтолог университета Лини в Китай, и съавтор на изследването, публикувано вчера (29 април) в списание Nature.

"Това е изумително откритие и аз мисля, че е един от най-неочакваните и откровено странни динозаври, които са открити през последните няколко години", е заявил Стивън Брусат (Stephen Brusatte), палеонтолог от университета в Единбург в Шотландия, неучаствал в проучването. Палеонтолозите предполагат, че вероятно способността за летене много пъти се е развивала у динозаврите, но само една група - птиците - са успели в това начинание.

 

[Last roman]

Липсващото звено в еволюцията на тиранозаврите най-накрая открито в Узбекистан:

New Dinosaur Discovery Could Solve Decades-Old Mystery

A horse-sized tyrannosauroid may help explain how the small, toothy predators of the Early Cretaceous evolved into the colossal carnivores that dominated from 80 to 66 million years ago. The mid-sized Timurlengia euotica from Middle Cretaceous Uzbekistan is the long-awaited intermediate tyrannosauroid: It had yet to develop the size of T. rex and its close cousins, but it already boasted some sophisticated brain and sensory features. The findings are published in the Proceedings of the National Academy of Sciences this week. 

Thanks to their gigantic size and keen senses, apex predators like Tyrannosaurus andAlbertosaurus enjoyed a spot at the top of the food chain in both Asia and North America up until the end-Cretaceous mass extinction event. But how these latest Cretaceous giants (called tyrannosaurids) came to dominate is still unclear because of a frustrating 20-million-year gap in the tyrannosaur fossil record.

We know that they evolved from an ancestral lineage of basal tyrannosauroids, which originated more than 100 million years before T. rex. The group first appeared in the fossil record of the Middle Jurassic around 170 million years ago, but they remained second-tier predators for most of their history – rarely exceeding the mass of a horse. 

Now, University of Edinburgh’s Stephen Brusatte and colleagues have discovered a new tyrannosaur species that bridges the gap – in both size and age – between the marginal hunters of the Early Cretaceous and the tyrannosaurids. Timurlengia euotica was recovered from the Bissekty Formation in the Kyzylkum Desert of Uzbekistan. It lived around 90 to 92 million years ago, and it weighed 170 to 270 kilograms (370 to 595 pounds). 

When the team used X-ray computed microtomography scanning to visualize the internal structures of the well-preserved fossil braincase, they found the signature brain and inner ear features of the latest Cretaceous forms. The new genus is named after the 14th-century Central Asian ruler Timurleng, and the new species name means "well eared," a reference to the large inner ear. 

"To be honest, I didn't quite know what to expect in a mid-Cretaceous tyrannosaur. It was such a big gap in the fossil record that really anything was possible," Brusatte tells IFLScience. "I would have predicted that they would have been bigger. Maybe not T. rexsize, but bigger than a horse for sure."

Analyses into its evolutionary relationships revealed that Timurlengia euotica occupies an intermediate position in the family tree between the oldest, smallest tyrannosauroids and the largest, last-surviving tyrannosaurids. While Timurlengia is just one data point from a "still murky interval in dinosaur history," it suggests that enormous size developed rapidly during the latest Cretaceous. The success of Tyrannosaurus and its close kin was likely enabled by innovations that first evolved at a far smaller body size.

"The advanced brains and senses may have been some of the features that allowed tyrannosaurs to step into the large predator role, and become so successful at it," Brusatte adds. "Opportunity arose when the incumbent giant predators (the allosaurs) mysteriously went extinct."

http://www.iflscience.com/plants-and-animals/horse-sized-t-rex-relative-found-uzbekistan

[Last roman]

нова теория за измирането на динозаврите;

Dinosaur Extinction May Have Been Caused By An "Interstellar Cloud"

http://www.iflscience.com/space/dinosaur-extinction-may-have-been-caused-interstellar-cloud

[Last roman]

предшественик на маларията открит в комар на възраст 100 млн. години. Явно динозаврите са си патили от заболяването:

http://www.iflscience.com/plants-and-animals/ancestor-malaria-may-have-once-infected-dinosaurs

[Р. Теодосиев]

Новооткрит динозавър има малки "ръце" като на Т-рекс: http://www.popularmechanics.com/science/animals/a21813/gualicho-dinosaur-small-arms-t-rex/

 

[Warlord]

Идеално запазена опашка на динозавър в кехлибар. Люспестите изображения май окончателно ще бъдат заменени с пернати

 

http://news.nationalgeographic.com/2016/12/feathered-dinosaur-tail-amber-theropod-myanmar-burma-cretaceous/?utm_source=Facebook&utm_medium=Social&utm_content=link_fb20161208news-feathereddino&utm_campaign=Content&sf45504119=1