WORLD'S OLDEST BIRDS — FROM CHINA?
Gigantoraptor, bird-like dinosaur
China is a treasure trove for feathered dinosaur fossils and dinosaur-era birds. Birds arose from small, feathered dinosaurs. Crow-sized Archaeopteryx, which lived about 150 million years ago, and was discovered in Germany in 1861, is considered the earliest known bird. But many dinosaurs before and after that had feathers and other bird-like characteristics.
“Confuciusornis sanctus”, a 150-million-year-old bird found in Liaoning, is considered a candidate for the earliest bird ever found. It had a toothless beak, feathered wings, claws that could be used to climb trees, feathers like modern birds and long tail feathers reminiscent of those found in some tropical birds and birds of paradise. Named in honor of the Chinese sage, “Confuciusonris” lived during the Jurassic period. Most early birds date back to the later Cretaceous period and scientist have speculated that they evolved from Jurassic age dinosaurs. Fossils of a primitive bird called “Protopteryx” contains three different kinds of feathers: downy feathers on the head and body, true flight feathers and scalelike central tail feathers.
Ian Sample wrote in The Guardian: “A prehistoric beast the size of a pheasant has become a contender for the title of oldest bird to stalk the Earth. The small, feathered "Dawn" bird lived around 160 million years ago, about 10 million years before Archaeopteryx, which holds the official title of the earliest bird known to science. The new species, which scientists have named Aurornis xui, had claws and a long tail, with front and hind legs similar to those of Archaeopteryx, but some features of its bones were more primitive. It measured 50cm from its beak to the tip of its tail. [Source:Ian Sample, The Guardian, May 29, 2013]
“Encased in sedimentary rock, the fossil preserved traces of downy feathers along the animal's tail, neck and chest, but the absence of larger feathers suggests it was not able to fly. When scientists reconstructed the evolutionary tree of similar beasts using measurements from their skeletons, A xui appeared on the bird lineage, but closer to the base of the tree than Archaeopteryx. "It's an important fossil," said Gareth Dyke, a senior palaeontologist involved in the study at Southampton University. "Aurornis pushes Archaeopteryx off its perch as the oldest member of the bird lineage."
“Scientists at the Yizhou Fossil and Geology Park in north-eastern China bought the remains from a local fossil dealer, who claimed they had been unearthed in Yaoluguo in western Liaoning, where sedimentary rock was laid down 153 million to 165 million years ago. It is not uncommon for scientists to work with fossil dealers, but it can be a risky business. Unless experts can confirm where a fossil came from, it can be impossible to gauge their age.
Discovery of Confuciusornis, Dinosaur-Age Bird
In 1995, Zhou Zhonghe, one of China's star paleontologists, and colleagues announced the discovery of a fossil from Liaoning zone that heralded a new age of paleontology. The fossil was a primitive bird the size of a crow that may have been asphyxiated by volcanic fumes as it wheeled above the lakes all those millions of years ago. They named the new species Confuciusornis, after the Chinese philosopher.” [Source: Richard Stone, Smithsonian magazine, December 2010]
Richard Stone wrote in Smithsonian magazine, “Until then, only a handful of prehistoric bird fossils had been unearthed anywhere in the world. That's partly because birds, then as now, were far less common than fish and invertebrates, and partly because birds more readily evaded mudslides, tar pits, volcanic eruptions and other geological phenomena that captured animals and preserved traces of them for the ages. Scientists have located only ten intact fossilized skeletons of the earliest known bird, Archaeopteryx, which lived at the end of the Jurassic period, about 145 million years ago.”
“Zhou, who works at the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences in Beijing, believed that the extraordinary bone beds in Liaoning might fill in some of the many blanks in the fossil record of the earliest birds. He couldn't have been more prophetic. In the past 15 years, thousands of exquisitely preserved fossil birds have emerged from the ancient lakebed, called the Yixian Formation. The region has also yielded stunning dinosaur specimens, the likes of which had never been seen before. As a result, China has been the key to solving one of the biggest questions in dinosaur science in the past 150 years: the real relationship between birds and dinosaurs.”
Theory That Birds Evolved from Dinosaurs
Richard Stone wrote in Smithsonian magazine, “The idea that birds — the most diverse group of land vertebrates, with nearly 10,000 living species — descended directly from dinosaurs isn't new. It was raised by the English biologist Thomas Henry Huxley in his 1870 treatise, Further Evidence of the Affinity between the Dinosaurian Reptiles and Birds. Huxley, a renowned anatomist perhaps best remembered for his ardent defense of Charles Darwin's theory of evolution, saw little difference between the bone structure of Compsognathus, a dinosaur no bigger than a turkey, and Archaeopteryx, which was discovered in Germany and described in 1861. When Huxley looked at ostriches and other modern birds, he saw smallish dinosaurs. If a baby chicken's leg bones were enlarged and fossilized, he noted, "there would be nothing in their characters to prevent us from referring them to the Dinosauria." [Source: Richard Stone, Smithsonian magazine, December 2010]
“Still, over the decades researchers who doubted the dinosaur-bird link also made good anatomical arguments. They said dinosaurs lack a number of features that are distinctly avian, including wishbones, or fused clavicles; bones riddled with air pockets; flexible wrist joints; and three-toed feet. Moreover, the posited link seemed contrary to what everyone thought they knew: that birds are small, intelligent, speedy, warmblooded sprites, whereas dinosaurs — from the Greek for "fearfully great lizard" — were coldblooded, dull, plodding, reptile-like creatures.”
“In the late 1960s, a fossilized dinosaur skeleton from Montana began to undermine that assumption. Deinonychus, or "terrible claw" after the sickle-shaped talon on each hind foot, stood about 11 feet from head to tail and was a lithe predator. Moreover, its bone structure was similar to that of Archaeopteryx. Soon scientists were gathering other intriguing physical evidence, finding that fused clavicles were common in dinosaurs after all. Deinonychus and Velociraptor bones had air pockets and flexible wrist joints. Dinosaur traits were looking more birdlike all the time. "All those things were yanked out of the definition of being a bird," says paleontologist Matthew Carrano of the Smithsonian National Museum of Natural History.”
“But there was one important feature that had not been found in dinosaurs, and few experts would feel entirely comfortable asserting that chickadees and triceratops were kin until they had evidence for this missing anatomical link: feathers.”
Dinosaurs with Feathers from China
“Sinosauropteryx” ("Chinese dragon-bird”) is a small bipedal birdlike dinosaur found at Liaoning in 1996. It was the first nonbird whose fossil included featherlike structures. It has been offered as proof that birds evolved from dinosaurs.
The “Archaeoraptor liaoningensis”, a creature found in 2000, has been described as the most definitive link between dinosaurs and birds because it had anatomical features found on dinosaurs and feathers. Scientists who made the discovery wrote in Nature, "It has things that are undeniably feathers...But is clearly a small vicious theropod similar to the velociraptors...in Jurassic Park."
This small duck-size dinosaur lied between 124 million and 147 million years ago. It had three different kinds of feathers: fuzz, hollow fibers of the head, plumlike "sprays" on the shoulders and filaments arranged in herring bone pattern in the backs of the arms and legs.
Scientist theorize the protofeathers could have first help keep the dinosaurs warm. Later their evolved into feather on the wings to help the creatures flap away like a chicken but nor truly fly so the could escape predators.
The fossil of a “mei long”, a species of dinosaur, was found with it head tucked under its forelimb. the position that birds adopt when they are sleeping to stay warm.
The “Gigantoraptor” is a giant birdlike dinosaur discovered in Inner Mongolia in 2007. Related to the oviraptorosaurs of the late Cretaceous Period’small 40-kilogram creatures with a toothless beak — it weighs more than one and half tons. It is not known what it ate with its large toothless beak or if it had feathers on its claw-tipped arms like other oviraptorosaurs.
Discovery of Dinosaur with Feathers
A 124-million-year-old fossil of a “ sinosauropteryx “, a small flesh-eating theropod, found in China has for the first time revealed the color of dinosaurs: reddish brown. In article published in Nature in February 2010, Mike Benton, a professor of paleontology at Britain’s Bristol University, announced the discovery using internal cellular coloring agents — not the colors themselves — found fossilized tail feathers found in the fossil.
Richard Stone wrote in Smithsonian magazine,”A poor Chinese farmer, Li Yingfang, made one of the greatest fossil finds of all time, in August 1996 in Sihetun village, an hour's drive from the site where I'd prospected for fossil fish. "I was digging holes for planting trees," recalls Li, who now has a full-time job at a dinosaur museum built at that very site. From a hole he unearthed a two-foot-long shale slab. An experienced fossil hunter, Li split the slab and beheld a creature unlike any he had seen. The skeleton had a birdlike skull, a long tail and impressions of what appeared to be feather-like structures.” [Source: Richard Stone, Smithsonian magazine, December 2010]
“Because of the feathers, Ji Qiang, then the director of the National Geological Museum, which bought one of Li's slabs, assumed it was a new species of primitive bird. But other Chinese paleontologists were convinced it was a dinosaur. On a visit to Beijing that October, Philip Currie, a paleontologist now at the University of Alberta, saw the specimen and realized it would turn paleontology on its head. The next month, Currie, a longtime China hand, showed a photograph of it to colleagues at the annual meeting of the Society of Vertebrate Paleontology. The picture stole the show. "It was such an amazing fossil," recalls paleontologist Hans-Dieter Sues of the National Museum of Natural History. "Sensational." Western paleontologists soon made a pilgrimage to Beijing to see the fossil. "They came back dazed," Sues says.”
“Despite the feathers, the skeleton left no doubt that the new species, named Sinosauropteryx, meaning "Chinese lizard wing," was a dinosaur. It lived around 125 million years ago, based on the dating of radioactive elements in the sediments that encased the fossil. Its integumentary filaments — long, thin structures protruding from its scaly skin — convinced most paleontologists that the animal was the first feathered dinosaur ever unearthed. A dozen dinosaurs with filaments or feathers have since been discovered at that site.”
“By analyzing specimens from China, paleontologists have filled in gaps in the fossil record and traced the evolutionary relationships among various dinosaurs. The fossils finally have confirmed, to all but a few skeptics, that birds descended from dinosaurs and are the living representatives of a dinosaur lineage called the Maniraptorans.
“Most dinosaurs were not part of the lineage that gave rise to birds; they occupied other branches of the dinosaur family tree. Sinosauropteryx, in fact, was what paleontologists call a non-avian dinosaur, even though it had feathers. This insight has prompted paleontologists to revise their view of other non-avian dinosaurs, such as the notorious meat eater Velociraptor and even some members of the tyrannosaur group. They, too, were probably adorned with feathers.”
Evolution of Feathers
Richard Stone wrote in Smithsonian magazine, “The abundance of feathered fossils has allowed paleontologists to examine a fundamental question: Why did feathers evolve? Today, it's clear that feathers perform many functions: they help birds retain body heat, repel water and attract a mate. And of course they aid flight — but not always, as ostriches and penguins, which have feathers but do not fly, demonstrate. Many feathered dinosaurs did not have wings or were too heavy, relative to the length of their feathered limbs, to fly.” [Source: Richard Stone, Smithsonian magazine, December 2010]
“Deciphering how feathers morphed over the ages from spindly fibers to delicate instruments of flight would shed light on the transition of dinosaurs to birds, and how natural selection forged this complex trait. Few scientists know ancient feathers more intimately than IVPP's Xu Xing. He has discovered 40 dinosaur species — more than any other living scientist — from all over China. His office at IVPP, across the street from the Beijing Zoo, is cluttered with fossils and casts.”
Xu envisions feather evolution as an incremental process. Feathers in their most primitive form were single filaments, resembling quills, that jutted from reptilian skin. These simple structures go way back; even pterodactyls had filaments of sorts. Xu suggests that feather evolution may have gotten started in a common ancestor of pterodactyls and dinosaurs — nearly 240 million years ago, or some 95 million years before Archaeopteryx.”
After the emergence of single filaments came multiple filaments joined at the base. Next to appear in the fossil record were paired barbs shooting off a central shaft. Eventually, dense rows of interlocking barbs formed a flat surface: the basic blueprint of the so-called pennaceous feathers of modern birds. All these feather types have been found in fossil impressions of theropods, the dinosaur suborder that includes Tyrannosaurus rex as well as birds and other Maniraptorans.”
“Filaments are found elsewhere in the dinosaur family tree as well, in species far removed from theropods, such as Psittacosaurus, a parrot-faced herbivore that arose around 130 million years ago. It had sparse single filaments along its tail. It's not clear why filaments appear in some dinosaur lineages but not in others. "One possibility is that feather-like structures evolved very early in dinosaur history," says Xu, and some groups maintained the structures, while other groups lost them. "But finally in Maniraptorans, feathers stabilized and evolved into modern feathers," he says. Or filaments may have evolved independently at different times. As Sues points out, "It seems that, genetically, it's not a great trick to make a scale into a filament."
“Originally, single filaments may well have been for display, the dinosaur equivalent of a peacock's iridescent plumage. Vivid evidence for that theory appeared when scientists unveiled the true colors of 125-million-year-old feathers. Bird feathers and reptile scales contain melanosomes — tiny sacs holding varieties of the pigment melanin. Many paleontologists suspected that dinosaur feathers also contained melanosomes. In Mike Benton's laboratory at the University of Bristol, IVPP's Zhang Fucheng spent more than a year searching for melanosomes in photographs of bird and dinosaur fossils taken with an electron microscope. Zhang's diligence paid off in 2009 when he pinpointed melanosomes in Confuciusornis that contained eumelanin, which gives feathers a gray or black tinge, and pheomelanin, which gives them a chestnut to reddish-brown color. The animal's feathers had patches of white, black and orange-brown coloring. “Sinosauropteryx was even more stunning. Zhang found that the filaments running down its back and tail must have made the dinosaur look like an orange-and-white-striped barber pole. Such a vibrant pattern suggests that "feathers first arose as agents for color display," Benton says.”
Purpose of Early Feathers
Richard Stone wrote in Smithsonian magazine, “Early feathers could have served other purposes. Hollow filaments may have dissipated heat, much as the frills of some modern lizards do today. Other paleontologists speculate feathers first evolved to retain heat. A telling example comes from fossils of Oviraptor — a theropod unearthed in Mongolia that lived around 75 million years ago’squatting over egg-filled nests. Oviraptors tucked their legs into the center of the clutch and hugged the periphery with their long forelimbs — a posture bearing an uncanny resemblance to brooding birds keeping their eggs warm. Dinosaurs related to Oviraptor were covered with pennaceous feathers, suggesting that Oviraptor was as well. "Sitting on a nest like that only made sense if it had feathers" to gently insulate its young, says Sues.” [Source: Richard Stone, Smithsonian magazine, December 2010]
“Feathers did, of course, eventually become an instrument of flight. Some paleontologists envision a scenario in which dinosaurs used feathers to help them occupy trees for the first time. "Because dinosaurs had hinged ankles, they could not rotate their feet and they couldn't climb well. Maybe feathers helped them scramble up tree trunks," Carrano says. Baby birds of primarily ground-dwelling species like turkeys use their wings in this way. Feathers may have become increasingly aerodynamic over millions of years, eventually allowing dinosaurs to glide from tree to tree. Individuals able to perform such a feat might have been able to reach new food sources or better escape predators — and pass the trait on to subsequent generations.”
Four-Winged Feathered Dinosaurs
In January 2003, Chinese scientist revealed the discovery of a “four-winged" dinosaur that had wings on its forelimbs and legs. The creature, given the name “Microraptor”, was about a meter long and appears to have “flown” by gliding using a method similar to that of flying squirrels. Xing Xu said, “The new fossils provide an example of the transition of dinosaurs to birds. They are the link between the flightless dinosaur and (flying) birds.”
In 2009, Xu discovered another species of four-winged dinosaur, also at Liaoning. Besides showing that four-winged flight was not a fluke, the new species, Anchiornis huxleyi, named in honor of Thomas Henry Huxley, is the earliest known feathered dinosaur. It came from Jurassic lakebed deposits 155 million to 160 million years old. The find eliminated the final objection to the evolutionary link between birds and dinosaurs. For years, skeptics had raised the so-called temporal paradox: there were no feathered dinosaurs older than Archaeopteryx, so birds could not have arisen from dinosaurs. Now that argument was blown away: Anchiornis is millions of years older than Archaeopteryx. Four-winged dinosaurs were ultimately a dead branch on the tree of life; they disappear from the fossil record around 80 million years ago. Their demise left only one dinosaur lineage capable of flight: birds.”
In 2014, scientists described the fossil of a strange dinosaur that lived in China 125 million years ago which was covered in feathers and looked like it had two sets of wings that may have enabled to glide but not fly. Will Dunham of Reuters wrote: It was built sort of like a biplane but probably did not fly as well, if at all. “The meat-eating creature, called Changyuraptor yangi, had exceptionally long tail feathers, the longest feathers of any dinosaur, at one foot in length (30 cm). It had feather-covered forelimbs akin to wings as well as legs covered in feathers in a way that gave the appearance of a second set of wings. Changyuraptor was unearthed in Liaoning. The study was published in the journal Nature Communications.[Source:Will Dunham, Reuters, July 15, 2014]
“Changyuraptor is not considered a bird but rather a very bird-like dinosaur. It illustrates that it is not always easy to tell what is and is not a bird. It measured a bit more than 4 feet long (1.3 meters) and weighed roughly 9 pounds (4 kg). If a person saw Changyuraptor, the reaction likely would be: "Hey! That is a weird-looking bird," according to paleontologist Alan Turner of Stony Brook University in New York, one of the researchers. "So, think a mid-sized turkey with a very long tail," Turner added. Scientists have identified a handful of these 'four-winged' dinosaurs, known as microraptorines. Changyuraptor is the largest. "Changyuraptor is very, very similar to Archaeopteryx and other primitive birds. So are many other dinosaurs like Anchiornis and Pedopenna. But they have some traits that birds lack, and lack some traits that birds have," Turner added.
“Natural History Museum of Los Angeles County paleontologist Luis Chiappe, who led the study, said Changyuraptor lived in a forested environment in a temperate climate, hunting birds, mammals, small reptiles and fish. "Animals like Changyuraptor were probably not engaged in powered flight like modern birds. However, Changyuraptor and dinosaurs like it could flap their wings and certainly had large feathered surfaces on both their forelimbs and hind limbs," Turner said. "So this does raise the possibility they could glide or 'fly' in a primitive sort of way. The way I like to think of it is: if you pushed them out of a tree, they'd fall pretty slowly," Turner added.
“If Changyuraptor were able to become airborne, its long tail feathers may have helped reduce descent speed and enabled safe landings. "This helps explain how animals like Changyuraptor could engage in some form of aerial locomotion — flight, gliding, and/or controlled descents — despite their size," Turner added. In birds today, feathers can serve multiple functions beyond flight, including display, species recognition and mating rituals. Turner said Changyuraptor's feathers also may have served multiple purposes.
Four-Winged Feathered Dinosaurs: Missing Links Between Dinosaurs and Birds?
Microraptor lived between 120 million and 110 million years ago. Xu and others argue that over time these creatures evolved into birds as their hind wings were lost. The existence of these creatures also offers evidence that the first flying bird-dinosaurs lept off trees or other high places rather then getting a running start and taking off from the ground. Richard Stone wrote in Smithsonian magazine, “One of the most beguiling specimens to emerge from Liaoning's shale beds is Microraptor, which Xu discovered in 2003. The bantamweight beast was a foot or two long and tipped the scales at a mere two pounds. Microraptor, from the Dromaeosaur family, was not an ancestor of birds, but it was also unlike any previously discovered feathered dinosaur. Xu calls it a "four-winged" dinosaur because it had long, pennaceous feathers on its arms and legs. Because of its fused breastbone and asymmetrical feathers, says Xu, Microraptor surely could glide from tree to tree, and it may even have been better at flying under its own power than Archaeopteryx was. [Source: Richard Stone, Smithsonian magazine, December 2010]
“Sinoventor changi”, another dinosaur discovered in the early 2000s in Liaoning, was a two-legged, chicken -size predator that probably had feathers and possessed a birdlike shoulder joint, a wishbone, and a pelvic bone that points backward. It was estimated to be about 130 million years old. “Incisivosaurus gauhhieri” lived about the same time. Described as a cross between a bird, a Tyrannosaurus rex and a beaver, it was the size of a turkey and had many birdlike features such as chisel-shaped teeth used for gnawing plants.
A fossilized dinosaur pelvis containing two unlaid eggs was found in Jiangxi Province. The animal, a female “oviraptorosaurian”, was bipedal, lived 65 million years ago and had two potato-shaped, pineapple-size eggs inside her. Scientist say that its reproductive system was more like a bird’s than a reptiles and it laid successive pairs of eggs rather one large clutch all at once. Like a bird the eggs were produced by a single ovary but like a reptile more than one egg could be laid at a time. Birds can only lay one egg at a time. Reptiles like crocodiles have two ovaries and can lay several eggs at once. The discovery was announced in April 2005. The specimen was found some time ago and is kept at the National Museum of Natural Science in Taiwan.
How Did Dinosaurs Become Birds?
Richard Stone wrote in Smithsonian magazine, “Just when did dinosaurs evolve into birds? Hard to say. "Deep in evolutionary history, it is extremely difficult to draw the line between birds and dinosaurs," says Xu. Aside from minor differences in the shape of neck vertebrae and the relative length of the arms, early birds and their Maniraptoran kin, such as Velociraptor, look very much alike. "If Archaeopteryx were discovered today, I don't think you would call it a bird. You would call it a feathered dinosaur," says Carrano. It's still called the first bird, but more for historic reasons than because it is the oldest or best embodiment of birdlike traits. On the other hand, Confuciusornis, which possessed the first beak and earliest pygostyle, or fused tail vertebrae that supported feathers, truly looks like a bird. "It passes the sniff test," Carrano says. [Source: Richard Stone, Smithsonian magazine, December 2010]
“Since the last of the non-avian dinosaurs died out 65 million years ago during the mass extinction that closed the curtain on the Cretaceous period, birds have evolved other characteristics that set them apart from dinosaurs. Modern birds have higher metabolisms than even the most agile Velociraptor ever had. Teeth disappeared at some point in birds' evolutionary history. Birds' tails got shorter, their flying skills got better and their brains got bigger than those of dinosaurs. And modern birds, unlike their Maniraptoran ancestors, have a big toe that juts away from the other toes, which allows birds to perch. "You gradually go from the long arms and huge hands of non-avian Maniraptorans to something that looks like the chicken wing you get at KFC," says Sues. Given the extent of these avian adaptations, it's no wonder the evolutionary link between dinosaurs and birds as we know them remained hidden until paleontologists started analyzing the rich fossil record from China.”
“In addition to Sinosauropteryx, several other revelatory specimens came to light through amateurs rather than at scientific excavations. The challenge for Zhou and his colleagues is to find hot specimens before they disappear into private collections. Thus Zhou and his colleague Zhang Jiangyong, a specialist on ancient fish at IVPP, have come to Liaoning province to check out any fossils that dealers friendly to their cause have gotten their hands on of late.”
Bird-Like Dinosaurs, Theropods and Birds
Among the other species with birdlike features found in Liaoning are “Protarchaeopteryx” and “Caudiperyx zoui”, dinosaurs that looked like little velocirpators with featherlike filaments on their bodies, tails and arms. These creatures lived 120 million to 140 million years ago. Scientist have coined the name Dromeosaur to describe a group ro two legged predators that share a common ancestor with birds. Dromeosaurs in turn belong to a subgroup of dinosaurs called theropods that share about 1,000 anatomical features with birds, including wishbones, swiveling wrists and three forward-pointing toes.
In the last 1990s, fossils of three flightless dinosaurs were found in Liaoning and studied by a team lead of Stephen Czerkas of the Dinosaur Museum in Blanding Utah. What was interesting about them is that they were theropods, or meat eaters, and included a couple of eagle-size dromaeosaurs, small raptors like the ones in “Jurassic Park”, and a two-meter therizinosaur, with the arms of a bird and the tail of a dinosaur that was described by some as the missing link between dinosaurs and birds and gave credence to a theory first proposed by John Ostrom of Yale that birds evolved from theropods. [Source: Christopher P. Sloan, National Geographic, November 1999]
One dromaeosaur, named Sinornothosaurus, had a shoulder bone more similar to a bird than a dinosaur. Another dromaesoaur had feathers very much like those on birds, The therizinosaur is the largest known dinosaur found with feathers, which were more likely used for insulation than flight. All three creatures lived about 120 million years ago. The theory goes these theropods were the first dinosaurs to have feathers. The feathers were initially used for warmth but later they helped the dinosaurs make leaping escapes and jumps and this evolved into flight over time.
In June 2009, a 155-million-year-old fossil was found in the Shishugu Formation in the Jungar Basin that provided important clues in understanding the evolution if bird-like dinosaurs. In a report in Nature, a team led by Chinese dinosaur expert Xing Xu said they discovered a young beaked herbivore — dubbed Limusaurus — that had feet configurations like those of birds, suggesting they have been early ancestors of birds.
Dinosaurs With Beaks and Feathers
In June 2007, a birdlike dinosaur the size of tyrannosaur was found in the Erhain basin in Inner Mongolia. The five-meter-high, 1,400-kilogram dinosaur, called “Gigantoraptor erlainensis”, had a beak, slender legs and likely had feathers. Its discovery indicates tar the evolution of dinosaurs and birds was much more complicated than previously thought.Xu Xing, a scientists at the Chinese Academy of Sciences in Beijing who led the team that made the discovery, told AP, “This is like having a mouse that is the size of a horse or a cow. It is very important information for us in our efforts to trace the evolution process of dinosaurs to birds. Its more complicated than we imagined.”
In 2016, an unusual birdlike dinosaur called Tongtianlong limosus was unearthed in the Ganzhou region of China. According to the New York Times: “It had feathers and a beak. It was the size of a donkey, and it did not fly. In a paper published in November 2016 in the journal Scientific Reports, a team of scientists described a fossil of Tongtianlong limosus, a new species in a strange group of dinosaurs that lived during the final 15 million years before dinosaurs became extinct. “They just look weird,” said Stephen L. Brusatte, a paleontologist at the University of Edinburgh in Scotland and one of the authors of the paper. Dr. Brusatte described it as “alien-looking” with a pug-nose skull and a crest. [Source: Kenneth Chang, New York Times, November 10, 2016]
The first fragmentary fossils of this group of dinosaurs known as oviraptorosaurs were found nearly a century ago; newly discovered, well-preserved specimens are revealing more details about them. Tongtianlong limosus — the name means “muddy dragon on the road to heaven” — is the sixth from the region of Ganzhou in Jiangxi province. This particular fossil was unearthed four years ago by fortunate happenstance during the construction of a school. “This one was found by workmen who were blasting with dynamite,” Dr. Brusatte said. “It’s a fine line sometimes between discovery and knowing nothing.”
“Oviraptorosaurs are not direct ancestors of birds, but share a common theropod dinosaur ancestor with the lineage that later evolved to birds. Some features like the feathers come from the common ancestor, for display to potential mates or other creatures. known theropods like velociraptors, “this guy was not a traditional meat eater,” Dr. Brusatte said. Perhaps it munched plants, nuts, insects, small animals or mollusks, Dr. Brusatte said. Or perhaps it ate a variety of foods. Or, as in birds, the beaks varied in shape among different species to feed in different ecological niches. “Beaks are really good multipurpose tools,” Dr. Brusatte said. The six Ganzhou oviraptorosaur species discovered so far are also very different from each other, and the scientists argue that this shows rapid evolution of these dinosaurs.
Fossil Shows Dinosaur Nesting on Eggs Like a Bird
In March 2021, scientists announced they had discovered a 70-million-year-old fossil of a non-avian dinosaur sitting atop a nest of eggs, with their fossil embryos intact, in Jiangxi Province of southern China. The discovery marks the first time a non-avian dinosaur has been found sitting atop its young and offered further evidence that birds evolved from dinosaurs.[Source: Matthew Hart, Nerdist, March 16, 2021]
The discovery was reported in the journal Science Bulletin. “Dinosaurs preserved on their nests are rare, and so are fossil embryos,” Dr.. Shundong Bi of Indiana University of Pennsylvania, said in a press release. “This is the first time a non-avian dinosaur has been found, sitting on a nest of eggs that preserve embryos, in a single spectacular specimen.”
The fossil consists of an incomplete skeleton of an adult oviraptorid — an omnivorous bird-like dinosaur— in a bird-like brooding position over a clutch of around 24 eggs. “This kind of discovery — in essence, fossilized behavior — is the rarest of the rare in dinosaurs,” paleontologist and project researcher, Dr. Matt Lamanna, said the release. “In the new specimen, the babies were almost ready to hatch, which tells us beyond a doubt that this oviraptorid had tended its nest for quite a long time.”
Pterosaurs in China
Flying dinosaurs called pterosaurs, which includes pterodactyls, dominated the skies for more than 160 million years until they went extinct alongside the dinosaurs some 66 million years ago. They are the largest animals to have ever flown, with some like the colossal Quetzalcoatlus having wingspans as large as fighter jets. In November 2017, paleontologists announced that had uncovered more than 200 fossilized eggs belonging to the flying reptiles in the journal Science, the largest collection of pterosaur eggs ever found. New York Times reported: “The species that laid the recently discovered eggs is known as Hamipterus tianshanensis. It lived during the early Cretaceous period and its wings stretched about 11 feet long. It also sported a thick forehead crest and had a mouth full of pointy teeth for snatching fish. [Source: Nicholas St. Fleur, New York Times, November 30, 2017]
“Xiaolin Wang, a paleontologist at the University of Chinese Academy of Sciences, Beijing, and lead author of the study, discovered the eggs in a 120-million-year-old pterosaur boneyard in the arid Gobi Desert in northwestern China. When the pterosaurs thrived, the place was most likely a lush lakeshore. The team suggested that a strong storm most likely washed the eggs into the lake, where they were buried alongside pterosaur bones and preserved for millions of years.
“Pterosaurs laid soft eggs like snakes or lizards, not brittle ones like birds. The fossilized eggs found at the nesting ground look more like deflated balloons than eggs cracked for an omelet. Dr. Kellner said it was also much more likely that pterosaurs laid their eggs in large nesting colonies near lake and river shores rather than in solitary nests high on cliffsides. He added that the large number of eggs they found suggested the pterosaurs returned to the nesting spot numerous times to lay their eggs. “Using CT-scanning, the team peered into the shells. Of the 215 eggs they found, 16 had embryonic remains, including one with partial wings and a toothless lower jaw. The team also discovered evidence that hatchlings had leg bones that were more developed than their forelimbs, suggesting the babies most likely crawled and were unable to fly. The team added that young pterosaurs were probably very reliant on their parents.
Kryptodrakon — Oldest Known Pterosaur — Found in China
The oldest known pterodactyl — Kryptodrakon — was found in China in 2014, and dated to 163 million years ago, pushing back the evolution of the ancient flying reptiles by five million years. The creature had a wingspan of 1.4 meters (4.5 feet) gets name from the Latin krypto (hidden) and drakon (serpent), a nod to the movie Crouching Tiger, Hidden Dragon, which was filmed in the desert in Xinjiang where the species was discovered.
According to National Geographic: “Scientists first discovered fragments of Kryptodrakon's delicate fossils in 2001 in northwestern China's remote Shishiugou Formation. That geologic formation has been called a "dinosaur death pit" because ancient quicksand entombed so many prehistoric creatures there. At first, Kryptodrakon's bones were misidentified as belonging to a type of two-legged dinosaur called a theropod, said James Clark, who co-authored the study published April 24 in the journal Current Biology. It wasn't until another scientist assembled the fossil parts into a skeleton several years later that "I looked at it and said, 'That's not a theropod, that's a pterosaur.' And the rest is history," said Clark, a biologist at George Washington University's Columbian College of Arts and Sciences in Washington, D.C. [Source: Christine Dell'Amore, National Geographic, April 24, 2014]
“Pterodactyls are a type of pterosaur, a wider group of flying reptiles that went extinct 66 million years ago. Because pterodactyl bones are so fragile, little is known about the origins of the ancient dinosaur relative, which eventually evolved into the biggest creature ever to take wing. “Another intriguing aspect of Kryptodrakon is that it was found—and likely lived—on an inland, forested floodplain. Previously, most pterodactyl fossils have been found near oceans.
Missing Link Pterosaur Found in China
In October 2009, British and Chinese scientists announced the discovery of the fossil of a 160-million-year-old pterosaur that they said provided a “missing link” in the understanding of flying dinosaurs also known as pterodactyls. The crow-size creature, dubbed Darwinopterus modularis in honor of Charles Darwin, lived 10 million years before the first bird and had wings and a head like other pterosaur but also had a long tail. The fossils were found in Zhucheng in Shandong Province. [Source: Agence France-Presse, October 14, 2009]
Palaeontologists, reporting in the British journal Proceedings of the Royal Society B, say more than 20 fossilized skeletons of the newly-uncovered species were found in northeastern China earlier in 2009. The finds were unearthed from rocks dated at around 160 million years ago, which places them close to the boundary line between the Middle and Late Jurassic periods, and at least 10 million years older than the first recognised bird, Archaeopteryx.
Darwinopterus appears to be intermediary between primitive, long-tailed pterosaurs (sometimes called pterodactyls) and their descendants, who were short-tailed, more sophisticated flyers that sometimes reached gigantic sizes. "Darwinopterus came as quite a shock to us," David Unwin of the University of Leicester, central England, said in a press release. "We had always expected a gap-filler with typically intermediate features such as a moderately elongated tail — neither long nor short — but the strange thing about Darwinopterus is that it has a head and neck just like that of advanced pterosaurs, while the rest of the skeleton, including a very long tail, is identical to that of primitive forms."
Darwinopterus had long jaws, rows of sharp teeth, and a flexible-looking neck, which suggests it may have survived on the wing by snatching small mammals or pigeon-sized feathery dinosaurs that were the forerunners of birds. "Darwinopterus" means "Darwin's wing", while "modularis" means composed of interchangeable units. The investigators, led by Junchang Lu of the Institute of Geology in Beijing, believe that pterosaurs went through bursts of evolution characterised by swift changes to groups of features. The head and neck evolved first, followed later by the body, tail, wings, and legs, they contend.
Image Sources: Chinese Academy of Sciences ; Asia Obscura
Text Sources: New York Times, Washington Post, Los Angeles Times, Times of London, National Geographic, The New Yorker, Time, Newsweek, Reuters, AP, Lonely Planet Guides, Compton’s Encyclopedia and various books and other publications.