Ancient mammals discovery in China


This video is called Ancient Mammals. Mammal evolution from the Triassic to now.

From Science News:

Fossils push back origins of modern mammals

Common ancestor evolved over 200 million years ago

by Meghan Rosen

2:39pm, September 10, 2014

Modern mammals’ ancestors may have emerged millions of years earlier than scientists suspected — around the time the first dinosaurs roamed the Earth.

The fossilized remains of six little tree-dwelling animals push the lineage of today’s mammals back to the Late Triassic, more than 200 million years ago, researchers report September 10 in Nature.

“That’s really, really old,” says paleontologist Robert Asher of the University of Cambridge, who was not involved with the work. Scientists had thought that the common ancestor of those animals originated sometime in the Jurassic, he says. “This is very exciting stuff.”

Xianshou songae is the name of the newly discovered dinosaur age mammal.

Welsh Jurassic mammals feeding, new study


This video says about itself:

There Are No Transitional Fossils?

19 April 2011

Long-sought fossil mammal with transitional middle ear found in China.

Palaeontologists have announced the discovery of Liaoconodon hui, a complete fossil mammal from the Mesozoic found in China that includes the long-sought transitional middle ear.

The specimen was found by palaeontologists from the American Museum of Natural History and the Chinese Academy of Sciences.

It shows the bones associated with hearing in mammals, the malleus, incus, and ectotympanic, decoupled from the lower jaw, as had been predicted, but were held in place by an ossified cartilage that rested in a groove on the lower jaw.

People have been looking for this specimen for over 150 years since noticing a puzzling groove on the lower jaw of some early mammals,” Jin Meng, curator in the Division of Palaeontology at the Museum and first author of the paper, said.

“Now we have cartilage with ear bones attached, the first clear paleontological evidence showing relationships between the lower jaw and middle ear,” Meng revealed

The transition from reptiles to mammals has long been an open question, although studies of developing embryos have linked reptilian bones of the lower jaw joint to mammalian middle ear bones.

The new fossil, Liaoconodon hui, fills the gap in knowledge between the basal, early mammaliaforms like Morganucodon, where the middle ear bones are part of the mandible and the definitive middle ear of living and fossil mammals.

Liaoconodon hui is a medium-sized mammal for the Mesozioc (35.7 cm long from nose to tip of tail, or about 14 inches) and dates from 125 to 122 million years.

It is named in part for the bountiful fossil beds in Liaoning, China, where it was found.

The species name, hui, honours palaeontologist Yaoming Hu who graduated from the American Museum of Natural History-supported doctoral program and recently passed away.

The fossil is particularly complete, and its skull was prepared from both dorsal and ventral sides, allowing Meng and colleagues to see that the incus and malleus have detached from the lower jaw to form part of the middle ear.

These bones remain linked to the jaw by the ossified Meckels cartilage that rests in the groove on the lower jaw. The team hypothesizes that in this early mammal, the eardrum was stabilized with the ossified cartilage as a supporting structure.

“Before we did not know the detailed morphology of how the bones of the middle ear detached, or the purpose of the ossified cartilage,” Meng said.

“Liaoconodon hui changes previous interpretations because we now know the detailed morphology of the transitional mammal and can propose that the ossified cartilage is a stabilizer.

“I”ve always dreamed of a fossil with a good ear ossicle. Now, we have had this once in a lifetime discovery,” Meng added.

From the University of Southampton in England:

Jurassic mammals were picky eaters, new study finds

August 20, 2014

Summary:

New analyses of tiny fossil mammals from Glamorgan, South Wales are shedding light on the function and diets of our earliest ancestors, a team reports. Mammals and their immediate ancestors from the Jurassic period (201-145 million years ago) developed new characteristics – such as better hearing and teeth capable of precise chewing.

New analyses of tiny fossil mammals from Glamorgan, South Wales are shedding light on the function and diets of our earliest ancestors, a team including researchers from the University of Southampton report today in the journal Nature. Mammals and their immediate ancestors from the Jurassic period (201-145 million years ago) developed new characteristics — such as better hearing and teeth capable of precise chewing.

By analysing jaw mechanics and fossil teeth, the team were able to determine that two of the earliest shrew-sized mammals, Morganucodon and Kuehneotherium, were not generalised insectivores but had already evolved specialised diets, feeding on distinct types of insects.

Lead author, Dr Pamela Gill of the University of Bristol, said: “None of the fossils of the earliest mammals have the sort of exceptional preservation that includes stomach contents to infer diet, so instead we used a range of new techniques which we applied to our fossil finds of broken jaws and isolated teeth. Our results confirm that the diversification of mammalian species at the time was linked with differences in diet and ecology.”

The team used synchrotron X-rays and CT scanning to reveal in unprecedented detail the internal anatomy of these tiny jaws, which are only 2cm in length. As the jaws are in many pieces, the scans were ‘stitched together’ to make a complete digital reconstruction. Finite element modelling, the same technique used to design hip joints and bridges, was used to perform a computational analysis of the strength of the jaws. This showed that Kuehneotherium and Morganucodon had very different abilities for catching and chewing prey.

Study co-author, Dr Neil Gostling from the University of Southampton, said: “The improvement in CT scanning, both in the instrumentation, at Light Source at the Paul Scherrer Institute in Switzerland where we scanned or even the µ-VIS Centre at Southampton, along with access for research of this kind, allows us to make inroads into understanding the biology and the ecology of animals long dead. The questions asked of the technology do not produce ‘speculation’, rather the results show a clearly defined answer based on direct comparison to living mammals. This would not be possible without the computational techniques we have used here.”

Using an analysis previously carried out on the teeth of present-day, insect-eating bats, the researchers found that the teeth of Morganucodon and Kuehneotherium had very different patterns of microscopic pits and scratches, known as ‘microwear’. This indicated they were eating different things with Morganucodon favouring harder, crunchier food items such as beetles while Kuehneotherium selected softer foods such as scorpion flies which were common at the time.

Team leader, Professor Emily Rayfield from the University of Bristol, added: “This study is important as it shows for the first time that the features that make us unique as mammals, such as having only one set of replacement teeth and a specialised jaw joint and hearing apparatus, were associated with the very earliest mammals beginning to specialise their teeth and jaws to eat different things.”

New dinosaur discovery in Venezuela


This video is called New type of dinosaur Laquintasaura venezuelae was turkey-sized.

From Wildlife Extra:

A new species of dinosaur that roamed northern South America 200 million years ago has been discovered in Venezuela.

This is the first time a dinosaur has been has been found here and in this honour it has been named Laquintasaura venezuelae.

Measuring about a metre long and 25 centimetres tall Laquintasaura would have been about the size of a small dog and belong to the ‘bird-hipped’, or Ornithischia, group of dinosaurs which later gave rise to Stegosaurus.

It was largely herbivorous- though the curve of some of its teeth suggest it might have also feasted on insects and small prey.

The discovery of it in small groups, which included juveniles and fully grown adults, could indicate they were living in herds; something that was not thought to have occurred in this sort of dinosaur until the Late Jurassic around 40 million years later.

‘It is fascinating and unexpected to see they lived in herds, something we have little evidence of so far in dinosaurs from this time,’ says lead author Dr Paul Barrett. “It’s always exciting to discover a new dinosaur species but there are many surprising firsts with Laquintasaura.”

See also here.

The scientific description of this new species is here.

Biggest ever apatosaurus discovery in Colorado


This video is called Origami Dinosaur: APATOSAURUS.

From the Grand Junction Free Press in the USA:

Record dinosaur bone found in Colorado quarry

By Brittany Markert

07/21/2014 12:01:00 AM MDT

Rabbit Valley’s Mygatt-Moore quarry is home to hundreds of fossils left behind by dinosaurs and extinct sea creatures. Its most notable recent find was a 6-foot-7-inch-long, 2,800-pound apatosaurus femur.

That is the largest apatosaurus ever found anywhere, said Dinosaur Journey curator of paleontology Julia McHugh.

It is a groundbreaking discovery because it belonged to a beast likely 80 to 90 feet long, which is 15 to 25 feet longer than average, she said.

After five summers of work excavating the dinosaur leg bone, it was lifted Thursday morning from the quarry outside Grand Junction near the Utah border. A crew of experts led by the Museum of Western Colorado’s Dinosaur Journey Museum oversaw the excavation.

“It’s funny that it was discovered from a small piece exposed about the size of a pancake,” volunteer Dorthy Stewart said.

The creature ordinarily grew up to 69 feet long and ate plants.

According to the National Park Service, “You may have heard it referred to by its scientifically incorrect name, Brontosaurus. This sauropod (long-necked dinosaur) was discovered and named Apatosaurus, or ‘false lizard,’ because of its unbelievably large size. After Apatosaurus was named, other sauropod specimens were named Brontosaurus. It was later determined that both names actually referred to the same animal, Apatosaurus.”

‘Birds descended not from dinosaurs, but from more ancient reptiles’


This video is called Wing evolution 1 of 4.

And these three videos are the sequels.

From Wildlife Extra:

Forensic examination reveals that birds did not descend from dinosaurs

The re-examination of a sparrow-sized fossil from China challenges the commonly held belief that birds evolved from ground-dwelling theropod dinosaurs that gained the ability to fly.

The birdlike fossil is not actually a dinosaur, as previously thought, but rather the remains of a tiny tree-climbing animal that could glide, say American researchers Stephen Czerkas of the Dinosaur Museum in Blanding, Utah, and Alan Feduccia of the University of North Carolina.

The study appears in Springer’s Journal of Ornithology.

Their findings validate predictions first made in the early 1900s that the ancestors of birds were small, tree-dwelling archosaurs which enhanced their incipient ability to fly with feathers that enabled them to at least glide.

This “trees down” view is in contrast with the “ground up” view embraced by many palaeontologists in recent decades that birds derived from terrestrial theropod dinosaurs.

The fossil of the Scansoriopteryx (which means “climbing wing”) was found in Inner Mongolia, and is part of an ongoing cooperative study with the Chinese Academy of Geological Sciences.

It was previously classified as a coelurosaurian theropod dinosaur, from which many experts believe flying dinosaurs and later birds evolved.

The research duo used advanced 3D microscopy, high resolution photography and low angle lighting to reveal structures not clearly visible before.

These techniques made it possible to interpret the natural contours of the bones.

Many ambiguous aspects of the fossil’s pelvis, forelimbs, hind limbs, and tail were confirmed, while it was discovered that it had elongated tendons along its tail vertebrae similar to Velociraptor.

Czerkas and Feduccia say that Scansoriopteryx unequivocally lacks the fundamental structural skeletal features to classify it as a dinosaur.

They also believe that dinosaurs are not the primitive ancestors of birds.

The Scansoriopteryx should rather be seen as an early bird whose ancestors are to be found among tree-climbing archosaurs that lived in a time well before dinosaurs.

Through their investigations, the researchers found a combination of plesiomorphic or ancestral non-dinosaurian traits along with highly derived features.

It has numerous unambiguous birdlike features such as elongated forelimbs, wing and hind limb feathers, wing membranes in front of its elbow, half-moon shaped wrist-like bones, bird-like perching feet, a tail with short anterior vertebrae, and claws that make tree climbing possible.

The researchers specifically note the primitive elongated feathers on the forelimbs and hind limbs.

This suggests that Scansoriopteryx is a basal or ancestral form of early birds that had mastered the basic aerodynamic maneouvers of parachuting or gliding from trees.

“The identification of Scansoriopteryx as a non-dinosaurian bird enables a re-evaluation in the understanding of the relationship between dinosaurs and birds,” explained Czerkas.

“Scientists finally have the key to unlock the doors that separate dinosaurs from birds.”

Feduccia added: “Instead of regarding birds as deriving from dinosaurs, Scansoriopteryx reinstates the validity of regarding them as a separate class uniquely avian and non-dinosaurian.”

Criticism of this: here.

Dinosaurs shrank for 50 million years to become birds: here.

Jurassic fly larva, parasite on salamanders, discovered


This video says about itself:

The fossil of two froghopper insects in the act of mating has been uncovered by archaeologists in northeastern China after being buried for around 165 million years.

From World Science:

Bizarre parasite from Jurassic found

June 25, 2014

Courtesy of the University of Bonn and World Science staff

Re­search­ers from the Uni­vers­ity of Bonn and from Chi­na have dis­cov­ered a fos­sil fly lar­va with such a spec­tac­u­lar suck­ing ap­pa­rat­us, they have named it by the Chin­ese word for “bizarre.”

Around 165 mil­lion years ago, a spec­tac­u­lar par­a­site was at home in the fresh­wa­ter lakes of pre­s­ent-day In­ner Mon­go­lia in Chi­na, re­search­ers say. It was a ju­ve­nile fly with a thor­ax, or “ch­est,” formed en­tirely like a suck­ing plate.

With it, the an­i­mal could stick to sala­man­ders and suck their blood with its mouth­parts formed like a sting, ac­cord­ing to sci­en­tists. To date no in­sect is known with a si­m­i­lar de­sign. The in­terna­t­ional sci­en­tif­ic team is now pre­sent­ing its find­ings in the jour­nal eLIFE.

The par­a­site, a long fly lar­va around two cen­time­ters (a bit un­der an inch) long, had un­der­gone ex­treme changes over the course of ev­o­lu­tion, the re­search­ers said. The head is ti­ny in com­par­i­son to the body, tube-shaped with piercer-like mouth­parts at the front. The mid-body, or thor­ax, has been com­pletely trans­formed un­derneath in­to a gi­gantic suck­ing plate; the hind-body, or ab­do­men, has caterpillar-like legs.

The re­search team be­lieves that this un­usu­al an­i­mal lived in a land­scape with vol­ca­noes and lakes what is now north­east­ern Chi­na around 165 mil­lion years ago. In this fresh wa­ter hab­i­tat, they say, the par­a­site crawled on­to pass­ing sala­man­ders, at­tached it­self with its suck­ing plate, and pen­e­trated the thin skin of the am­phib­ians in or­der to suck blood from them.

“The par­a­site lived the life of Reil­ly,” said paleon­tologist Jes Rust from the Uni­vers­ity of Bonn. This is be­cause there were many sala­man­ders in the lakes, as fos­sil finds at the same loca­t­ion near Ningcheng in In­ner Mon­go­lia (Chi­na) have shown. “There sci­en­tists had al­so found around 300,000 di­verse and ex­cep­tion­ally pre­served fos­sil in­sects,” said the Chin­ese sci­ent­ist Bo Wang, a post­doc­tor­al re­searcher in paleon­tology at the Uni­vers­ity of Bonn.

The lar­va, which has re­ceived the sci­en­tif­ic name of Qiyia juras­si­ca, how­ev­er, was a quite un­ex­pected find. “Qiyia” in Chin­ese means “bizarre”; “jur­as­si­ca” refers to the Ju­ras­sic pe­ri­od to which the fos­sils be­long. A fine-grained mud­stone en­sured the good state of pre­serva­t­ion of the fos­sil.

Biggest European carnivorous dinosaur discovery in Portugal


Torvosaurus tanneri in Madrid museum

From PLOS ONE:

Torvosaurus gurneyi n. sp., the Largest Terrestrial Predator from Europe, and a Proposed Terminology of the Maxilla Anatomy in Nonavian Theropods

Christophe Hendrickx, Octávio Mateus

Published: March 05, 2014

Abstract

The Lourinhã Formation (Kimmeridgian-Tithonian) of Central West Portugal is well known for its diversified dinosaur fauna similar to that of the Morrison Formation of North America; both areas share dinosaur taxa including the top predator Torvosaurus, reported in Portugal.

The material assigned to the Portuguese T. tanneri, consisting of a right maxilla and an incomplete caudal centrum, was briefly described in the literature and a thorough description of these bones is here given for the first time. A comparison with material referred to Torvosaurus tanneri allows us to highlight some important differences justifying the creation of a distinct Eastern species.

Torvosaurus gurneyi n. sp. displays two autapomorphies among Megalosauroidea, a maxilla possessing fewer than eleven teeth and an interdental wall nearly coincidental with the lateral wall of the maxillary body. In addition, it differs from T. tanneri by a reduced number of maxillary teeth, the absence of interdental plates terminating ventrally by broad V-shaped points and falling short relative to the lateral maxillary wall, and the absence of a protuberant ridge on the anterior part of the medial shelf, posterior to the anteromedial process.

T. gurneyi is the largest theropod from the Lourinhã Formation of Portugal and the largest land predator discovered in Europe hitherto. This taxon supports the mechanism of vicariance that occurred in the Iberian Meseta during the Late Jurassic when the proto-Atlantic was already well formed. A fragment of maxilla from the Lourinhã Formation referred to Torvosaurus sp. is ascribed to this new species, and several other bones, including a femur, a tibia and embryonic material all from the Kimmeridgian-Tithonian of Portugal, are tentatively assigned to T. gurneyi. A standard terminology and notation of the theropod maxilla is also proposed and a record of the Torvosaurus material from Portugal is given.

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