Paleontology
Editor-In-Chief: Henry A. Hoff
Paleontology is a study of fossils, plant and animal remains found on the Earth.[1]
Paleontology is a large subject because it includes aspects of geology and biology. Depending on the particular branch of paleontology studied, it may also require knowledge of chemistry, climatology, physics, and astronomy among others. It may also involve creating new techniques both in application and in theory. Paleontologists may work in outdoors, in an office or laboratory, or in a library; they may use a huge range of tools from bull dozers to computers.
The study of paleontology covers the entire history of life on Earth, which is about 4 billion years.
Paleontology is the branch of science dealing with study of past life. Paleontologists are the scientists that carry out this study.
The study of past life is done through the study of fossils which are evidence of that past life. Fossils may be the remains of organisms (plants, animals, etc.) or the remains of their activities (footprints, burrows, etc.). The later are called trace fossils.
Paleontology covers the entire span of life on Earth, from the first organisms around 4 billion years ago, up to the present day. However, scientists which study recent human activity, the last 12,000 years or so, are generally called archaeologists, and their study is called archaeology. There is a blurry line where archaeology begins and paleontology leaves off.
Paleontology is generally considered a part of geology, though because it involves life, it can also be considered a part of biology. Paleontologists must know something of both geology and biology. In particular in geology they must understand sedimentary geology - the study of sediments. In biology paleontologists need to know something about comparative anatomy, and in particular the anatomy of the organisms they study.
There are many sub-groups within paleontology, depending on what specifically is being studied. Among these is Vertebrate Paleontology (the study of fossil animals with backbones), Invertebrate Paleontology (the study of animals without backbones), Paleobotany (the study of fossil plants), and Paleoecology (the study of ancient environments). Almost everything within paleontology has it's own specialist name.
Theoretical paleontology
Def. the "[s]tudy of the forms of life existing in prehistoric or geologic times"[2] is called paleontology.
Clades from the paleontological rock record sometimes display a clade asymmetry. "(Our two cases of Metazoa and mammals represent the first filling of life's ecological "barrel" for multicellular animals, and the radiation of mammals into roles formerly occupied by dinosaurs.)"[3]
Fossils
Def. "[t]he mineralized remains of an animal or plant" or "[a]ny preserved evidence of ancient life, including shells, imprints, burrows, coprolites, and organically-produced chemicals"[4] is called a fossil.
Derived terms include ichnofossil, index fossil, living fossil, mesofossil, microfossil, and trace fossil.[4]
Colors
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{{fairuse}}"On December 9, 1833, the English fossil collector Elizabeth Philpot sent a letter to naturalist William Buckland. In addition to requesting back some vertebrae of a marine reptile Buckland had borrowed, Philpot also included notes on a recent trip with a young upstart fossil hound—the pioneering paleontologist Mary Anning. But what made the note special was an illustration Philpot had included with the letter. It depicted the toothy smile of an Ichthyosaurus skull, drawn after one of the many such fossils that Philpot, her sisters and Anning were finding in the ancient rocks of England’s southern coast. And it wasn’t drawn in any ordinary ink. The sepia tones were made from the preserved ink of a squid-like creature found in the same deposits as the ichthyosaur, revitalized after 200 million years."[5]
"On the surface, Philpot’s drawing might only seem to be a neat fossiliferous trick. In 2009, another drawing made from ancient ink kicked up renewed attention for the surprising fact that traces of prehistoric color could persist to the 21st century. But the fact that such primordial shades can be recovered at all opens up a realm of scientific possibility. With the right specimens, experts can start to color in the fossil record."[5]
"Researchers have known about fossil insect color patterns and mollusk color patterns all the way back to the Victorian era."[6]
"The biological key to solving the coloration puzzle comes down to miniscule structures called melanosomes. These are tiny, blobby organelles that contain pigment, or melanin, and are present in soft tissues such as skin, scales, and feathers. And while these details were often cast aside as fossil bacteria in decades past, renewed efforts in the 21st century have been able to find the relationship between these tiny structures and colors."[5]
"The discovery of preserved melanosomes opens up the possibility of interpreting the colour of extinct birds and other dinosaurs."[6]
"Pulling color from the past requires a combination of lucky finds with advanced imaging techniques."[7]
"First, paleontologists need a fossil which is likely to have preserved melanin—a fossil not just with bones, but feathers, skin or hair. These fossils often contain both melanosomes as well as chemically-degraded melanin pigment, and when paleontologists find such a fossil, then they can use modern technology to take a closer look."[5]
"You start by looking for the microbodies using instruments like scanning electron microscopes."[7]
"Once those characteristic shapes turn up, chemical analysis can confirm the presence of melanin pigment."[5]
"This was particularly critical early on in fossil melanin studies because there was still some doubt that the microbodies were in fact melanosomes and not other similar structures, like bacteria. From there, comparisons of the physical and chemical signatures of the melanosomes and melanin can be compared to those of living animals, for which color is known, to reconstruct the look of creatures long dead."[7]
"When paleontologists announced the discovery of the feathered dinosaur Anchiornis in 2009, the preserved plumage surrounding the skeleton was a dark, carbon-colored shade. But analysis of another Anchiornis fossil [...] the following year revealed a striking color pattern that had previously been invisible. The distribution and details of the preserved melanosomes indicated that Anchiornis was covered in feathers of black and white—not dissimilar from a magpie—with a splash of red feathers on the top of its head. For the first time, a dinosaur had been fully restored in living color."[5]
"The week before the Anchiornis paper came out, the small, fuzzy dinosaur Sinosauropteryx was shown to have a vibrant, red-and-white banded tail. In 2012, the stacked arrangement of melanosomes found in the feathers of four-winged dinosaur Microraptor was shown to create an iridescent sheen similar to that of a modern raven. (Avian dinosaurs joined the list, too, with giant fossil penguins bearing color patterns of black, red and gray.) And while early studies focused on feathers, paleontologists soon found that melanosomes can reveal the hues of scaly dinosaurs, too. The beaky, horned dinosaur Psittacosaurus was countershaded dark above and light below to help with camouflage, and the immense armored dinosaur Borealopelta sported reddish-brown tones."[5]
"Comparison [is] of melanosome proportions and body contour feather morphology in extinct penguins Inkayacu paracasensis (A and B) and representative extant penguins (C and D)."[5]
"In the case Borealopelta, for example—with a pattern of rusty red on top, light on bottom—the shading might have been a way for the low-slung dinosaur to hide from the ravenous tyrannosaurs of the time. Other dinosaurs were flashier. The candy-cane tail of Sinosauropteryx was likely a social signal, used by these dinosaurs to communicate with each other when they met."[5]
"The dinosaur [Sinosauropteryx] is portrayed in the predicted open habitat in which it lived around the Jehol lakes, preying on the lizard Dalinghosaurus."[5]
Micropaleontology
Micropaleontology is a study of fossil micro-organisms, including foraminifera, which have applications in stratigraphic correlation and age dating along with paleoecology and paleoclimatology.
The image at the right shows microspheric and megalospheric Nummulitid specimens.
Paleobotany
Paleobotany is the study of plant or plant-like fossils.
The image at the right shows fronds impressed onto shale in a specimen on display at the Paläontologische Museum München. The fossil is from Scalby Ness, Scarborough, England.
Palynology
Although regarded as a separate field of its own, in a real sense palynology is the micropaleontological equivalent of paleobotany that involves the study of fossil pollen and spores.
The image at right contains a spore tetrad (in green) of genus Scylaspora and trilete spores (blue, ~30-35μm diameter) from a late Silurian sporangium (Burgsvik beds, Sweden).
Invertebrate paleontology
Invertebrate paleontology is a study of fossil invertebrate animals, those which lack a backbone. Included are magafaunas whose study doesn't require a microscope, found in various phyla. Applications include stratigraphic dating and correlation, and paleo-ecology.
At the right is an example of invertebrate paleontology, specifically bryozoan fossils in an Ordovician oil shale from Estonia.
Vertebrate paleontology
Vertebrate paleontology is any study of prehistoric animals with backbones, e.g. fish of various kinds, marine and terrestrial reptiles, dinosaurs, birds, and mammals.
As a representative of vertebrate paleontology, the image at the right shows a skeleton of Mosasaurus hoffmannii on display at the Natural History Museum of Masstricht.
Paleoecology
{{free media}}In the image on the right, a group of Brancasaurus brancai are portrayed in an artists impression of their natural habitat together with some pycnodontiformes, Caturus and Hybodus in the far background.
Paleoclimatology
Paleoclimatology is the study of ancient climates. This helps paleontologists understand the environments that existed over the history of the Earth.
Paleoclimatology is also particularly important in understanding how climate might change in the future.
Geologic time
At right is a geologic clock representation. It shows some of the major units of geological time and definitive events of Earth history. The Hadean eon represents the time before fossil record of life on Earth; its upper boundary is now regarded as 4.0 Ga (billion years ago).[8] Other subdivisions reflect the evolution of life; the Archean and Proterozoic are both eons, the Palaeozoic, Mesozoic and Cenozoic are eras of the Phanerozoic eon. The two million year Quaternary period, the time of recognizable humans, is too small to be visible at this scale.
The following four timelines show the geologic time scale. The first shows the entire time from the formation of the Earth to the present, but this compresses the most recent eon. Therefore the second scale shows the most recent eon with an expanded scale. The second scale compresses the most recent era, so the most recent era is expanded in the third scale. Since the Quaternary is a very short period with short epochs, it is further expanded in the fourth scale. The second, third, and fourth timelines are therefore each subsections of their preceding timeline as indicated by asterisks. The Holocene (the latest epoch) is too small to be shown clearly on the third timeline on the right, another reason for expanding the fourth scale. The Pleistocene (P) epoch. Q stands for the Quaternary period.
Cenozoic Era
{{free media}}After the dinosaurs became extinct, the Cenozoic began.
The Cenozoic Era is comprised of the following:
- Quaternary Period (2.588 mya to present)
- Anthropocene Epoch (up to the present)
- Holocene Epoch (11,700 yrs to the beginning of the Anthropocene)
- Pleistocene Epoch (2.588 mya to 11,700 yrs)
- Neogene Period (23.03 to 2.588 mya)
- Pliocene Epoch (5.332 to 2.588 mya)
- Miocene Epoch (23.03 to 5.332 mya)
- Paleogene Period (65.5 to 23.03 mya)
- Oligocene Epoch (33.9 to 23.03 mya)
- Eocene Epoch (55.8 to 33.9 mya)
- Paleocene (65.5 to 55.8 mya)
Anthropocene Epoch
The Anthropocene Epoch is a newly added geologic time period. It is the "age of humans", when human activity grew to be the dominant force in shaping the Earth. The time of the beginning of this Epoch has not been completely settled upon. Claims run from 12,000 years ago when widespread agriculture began, to 1945 C.E. when the first atomic bomb was exploded.
For purposes of paleontology, the Anthropocene is primarily ignored, and is relegated to the science of archaeology, or the study of history, depending on when it is considered to have begun.
Holocene Epoch
{{free media}}The Holocene starts at ~11,700 b2k and extends to the beginning of the Anthropocene Epoch.
Pleistocene Epoch
{{free media}}The Pleistocene dates from 2.588 x 106 to 11,700 b2k.
People appear.
GIS 3
The stronger GIS 3 interstadial occurred about 27.6 kyr B.P.[9]
"In the Karginian Age (MIS 3) alluvial deposits of the described locality [occur] the remains of Elasmotherium sibiricum, Mammuthus ex gr. trogontherii-chosaricus, Mammuthus primigenius, Bison sp. AMS Radiocarbon dating of the Elasmotherium skull gave a young age - 26038 ± 356 BP (UBA-30522)."[10]
Hasselo stadial
{{free media}}The "Hasselo stadial [is] at approximately 40-38,500 14C years B.P. (Van Huissteden, 1990)."[11]
"The rhinoceros Elasmotherium sibiricum, known as the ‘Siberian unicorn’, was believed to have gone extinct around 200,000 years ago—well before the late Quaternary megafaunal extinction event. However, no absolute dating, genetic analysis or quantitative ecological assessment of this species has been undertaken. [By] accelerator mass spectrometry radiocarbon dating of 23 individuals, including cross-validation by compound-specific analysis, [...] E. sibiricum survived in Eastern Europe and Central Asia until at least 39,000 years ago, corroborating a wave of megafaunal turnover before the Last Glacial Maximum in Eurasia, in addition to the better-known late-glacial event. Stable isotope data indicate a dry steppe niche for E. sibiricum and, together with morphology, a highly specialized diet that probably contributed to its extinction. [With] DNA sequencing data, a very deep phylogenetic split between the subfamilies Elasmotheriinae and Rhinocerotinae [occurred] that includes all the living rhinoceroses, settling a debate based on fossil evidence and confirming that the two lineages had diverged by the Eocene. As the last surviving member of the Elasmotheriinae, the demise of the ‘Siberian unicorn’ marked the extinction of this subfamily."[12]
Pliocene Epoch
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{{free media}}The Pliocene ranges from 5.332 x 106 to 2.588 x 106 b2k.
Miocene Epoch
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{{fairuse}}The Miocene dates from 23.03 x 106 to 5.332 x 106 b2k.
"A giant goose that lived on a Mediterranean island between six and nine million years ago had wings tailored for combat."[13]
"Weighing 22 kilograms and standing perhaps 1.5 metres tall, Garganornis ballmanni might be the biggest member of the duck, goose and swan family ever to have lived. Its fossilised bones have been found at Gargano and Scontrone in central Italy – a region that, during the Miocene, consisted of islands populated by unique species."[13]
"Its wing bones are short for its size, suggesting it couldn’t fly. [The] carpometacarpus bone – equivalent to the hand bones in humans – had a rounded lump called the carpal knob, a feature present in modern birds that fight each other over territory. These include some ducks, geese and the extinct Rodrigues solitaire, the closest relative of the dodo."[13]
“It’s covered over with hard skin, so it becomes a really effective weapon. In solitaires, they certainly broke each others’ bones.”[14]
"Battles over territory are the most likely reason for Garganornis‘s fighting adaptation."[14]
"Ducks and geese that live on islands, such as the extinct moanalo of Hawaii, often evolve to be terrestrial and territorial. That’s because fresh water is often in short supply, and so they live in forests as herbivores."[13]
“You’ve got this big bird, with its wings used for fighting, that would have been incredibly aggressive and would have been able to defend its young against most predators.”[14]
Fossils "from the Early Miocene St Bathans Fauna of New Zealand [attest] to the former existence of a giant psittaciform, which is described as a new genus and species [image on the left]. The fossils are two incomplete tibiotarsi from a bird with an estimated mass of 7 kg, double that of the heaviest known parrot, the kakapo Strigops habroptila. These psittaciform fossils show that parrots join the growing group of avian taxa prone to giantism in insular species, currently restricted to palaeognaths, anatids, sylviornithids, columbids, aptornithids, ciconiids, tytonids, falconids and accipitrids."[15]
"Insular avifaunas are renowned for the evolution of novelties, usually in the form of extraordinarily large and flightless members of widespread and well-known lineages [1–4]. Preeminent among these is the columbid Dodo Raphus cucullatus of Mauritius [5], but the list includes giant Sylviornithidae on New Caledonia (Sylviornis) and Fiji (Megavitiornis) [6–8], other giant columbids on Rodrigues (Pezophaps) and on Fiji (Natunaornis) [5,9], giant waterfowl on Hawaii [10] and Malta [11], a giant ciconiid stork on Flores, Indonesia [12], and giant tytonid owls and other raptors in the Caribbean [13–16]. Insular rails (Rallidae) tend to be larger than mainland relatives, but the largest, the Takahe (Porphyrio hochstetteri) from New Zealand (NZ), at up to 3.2 kg, is smaller than these insular giants [17,18]."[15]
"Since moa were first reported in 1839 [22], NZ has become recognized as the epitome of the phenomenon of island giantism in birds. In addition to nine moa species (Dinornithiformes), two flightless anserines (Cnemiornis, Anatidae), two gruiforms (Aptornis, Aptornithidae) and a huge eagle (Hieraaetus moorei, Accipitridae) evolved from small ancestors into giant elements of the Holocene avifauna [23–28]."[15]
"The fossils, catalogued in the Museum of New Zealand Te Papa Tongarewa collections, are shafts of left and right tibiotarsi probably of one individual [image on the left]. [...] Tibiotarsi of Heracles inexpectatus gen. et sp. nov., left, holotype (a,b,f) NMNZ S.51083 and right, paratype (g), compared to (d,e) left tibiotarsus of Strigops habroptila (Canterbury Museum Av45277), in craniolateral (a) and cranial (b–g) views. (c) Silhouettes of a human and Heracles for scale. Scale bars are 20 mm. Abbreviations: ccl, crista cnemialis lateralis; cl, condylus lateralis; cm, condylus medialis; dtl, distal insertion scar for transverse ligament; fc, fibular crest; lfr, lateral scar for fibular retinaculum; lic, linea intermuscularis cranialis; mfr, mediocranial scar for fibular retinaculum; pons, pons supratendineus; ptl, proximal insertion scar for transverse ligament; se, sulcus extensorius; sf, sulcus m. fibularis; trf, tuberculum retinaculi m. fibularis. Human silhouette from PhyloPic, by T. M. Keesey."[15]
Fossils of Heracles inexpectatus are from a "conglomerate, 9.5–9.58 m above base of Bannockburn Formation, Early Miocene, 19–16 Ma [32]".[15]
"The holotype of Heracles inexpectatus is the largest fossil bone known among several thousand specimens in the fauna and adds a giant psittaciform to it."[15]
"The St Bathans Fauna has already revealed evidence for an Early Miocene radiation of parrots (Psittaciformes) in NZ, with three small nestorids described in Nelepsittacus, and another the size of Nestor notabilis [34]. Extant nestorids are grouped in Nestor as the sister taxon to Strigops habroptila; the two groups combined form the NZ endemic clade Strigopoidea that is the sister taxon of remaining psittaciforms [39]. Strigops habroptila is the heaviest and only flightless psittaciform [38,40], with legbones the largest among parrots [35]. Heracles inexpectatus has similar proportions and morphology to S. habroptila, but is much larger, differing qualitatively in greater medial projection of the proximomedial scar of the transverse ligament and less projection of the lateral fibular retinaculum scar [image on the left], the last relating to less climbing ability [34]. All known fossil parrots are much smaller than Strigops [34]. Given this similarity and its provenance, the affinity of Heracles inexpectatus may lie with Strigopoidea. The short separation of the mediocranial fibular retinaculum scar from the condyle suggests closer affinity to strigopids than nestorids [34]."[15]
Oligocene Epoch
{{free media}}The Oligocene dates from 33.9 ± 0.1 x 106 to 23.03 x 106 b2k.
The Oligocene Epoch covers 34 - 23 Mya.[16]
"As the Earth began to cool, the tropical plants that had previously been found relatively widespread began to recede towards the equator where it was still warm. The general tropical plants began a transition to more forest like areas. The first grasses also appeared in the late Oligocene. The appearance of these grasses led to to evolution of various herbivore animals. With bodies low to the ground, animals would take advantage of the new grasses that appeared."[16]
Eocene Epoch
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{{fairuse}}The Eocene dates from 55.8 ± 0.2 x 106 to 33.9 ± 0.1 x 106 b2k.
"Death came suddenly for the young fish darting through a lake roughly 50 million years ago."[17]
A "stone slab [in the image on the left] from the western United States [...] includes the fossils of 257 now-extinct fish (Erismatopterus levatus) bunched together in a dense swarm."[17]
Each "fish’s orientation and position" have been analyzed.[17]
The "ancient fish followed two rules used by their modern counterparts. An individual was repelled by its closest companions — to avoid collisions — and attracted to those farther away, which encouraged clumping. Like a modern-day school, the fossilized grouping had an elongated shape that might have helped to ward off predators."[17]
Paleocene Epoch
{{free media}}The Paleocene dates from 65.5 ± 0.3 x 106 to 55.8 ± 0.2 x 106 b2k.
Mesozoic Era
With another mass extinction Mezozoic era started. Now dinosaurs rule.
The Mesozoic Era is divided into the Cretaceous, Jurassic, and Triassic Periods.
"A high diversity of terrestrial vertebrates with dinosaurs as the dominant group is strongly indicated but not much of it is yet recorded."[18]
For much of the dinosaur era, the smallest sauropods are larger than anything else in their habitat, and the largest are an order of magnitude more massive than anything else that has since walked the Earth.
Cretaceous Period
"The Cretaceous period is the third and final period in the Mesozoic Era. It began 145.5 million years ago after the Jurassic Period and ended 65.5 million years ago, before the Paleogene Period of the Cenozoic Era."[19]
Late Cretaceous
Rock strata from the Late Cretaceous epoch form the Upper Cretaceous series.
The Late Cretaceous (100.5–66 Ma) is the younger of two epochs, the other being the Early Cretaceous, into which the Cretaceous period is divided in the geologic timescale.
Maastrichtian
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{{fairuse}}The Maastrichtian is the most recent stage of the upper Cretaceous from 66.0 - 72.1 Ma. The mummified Edmontosaurus annectens in the image on the right is from the Maastrichtian.
The Lameta Formation is a sedimentary rock formation found in Madhya Pradesh, Gujarat, and Maharashtra, India, of Maastrichtian age (Upper Cretaceous), notable for its dinosaur fossils, several genera of dinosaurs from these rocks, including the titanosaur sauropod Isisaurus, the abelisaurs Indosaurus, Indosuchus, Laevisuchus, and Rajasaurus and possible stegosaurs.[20][21]
Traditionally, pterosaur faunas of the Maastrichtian appeared to be dominated by Azhdarchidae, with other pterosaur groups having become extinct earlier on, but, more recent findings suggest a fairly composite pterosaur diversity: at least six (Nyctosaurus lamegoi, a Mexican humerus, a Jordan humerus and several taxa from Morocco) Nyctosauridae date to this period, as do a few Pteranodontidae, and Navajodactylus, tentatively assigned to Azhdarchidae, lacking any synapomorphies of the group.[22][23] This seems to underscore a higher diversity of terminal Cretaceous pterosaurs than previously thought.[24][25][26]
The specimen second down on the left is Jeletzkytes spedeni from the Maastrichtian (Upper-Cretaceous) Fox Hills Formation, locality - South Dakota, USA. Matrix free specimen is 7.5 cm (3") in diameter, displaying pearly aragonite preservation of the shell.
The type species of Hainosaurus is H. bernardi, named after the Belgian Léopold Bernard, owner of the phosphate chalk exploitation where the fossil was unearthed.[27] In a paper published in 2016, Hainosaurus was considered congeneric with Tylosaurus.[28]
Campanian
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The Campanian was an age when a worldwide marine transgression or sea level rise drowned many coastal areas, preserved as an unconformity beneath a cover of marine sedimentary rocks.[29][30]
During the Campanian age, an evolutionary radiation among dinosaur species occurred, where in North America, for example, the number of known dinosaur genera rises from 4 at the base of the Campanian to 48 in the upper part, sometimes referred to as the "Campanian Explosion" the generally warm climates and large continental area covered in shallow sea during the Campanian probably favoured the dinosaurs, but in the following Maastrichtian stage, the number of North American dinosaur genera found is 30% less than in the upper Campanian.[31]
The image on the right shows a juvenile Chasmosaurus fossil seen from the side.
"The Ceratopsidae are one of the more immediately recognizable groups of dinosaurs. Characterized by sharp beaks and flamboyant horns and frills, these herbivores almost all lived in what is now Western North America right at the end of the Cretaceous period, 100 to 66 million years ago."[32]
"Chasmosaurus belonged to this group [...] The 75 million-year-old fossilized Chasmosaurus was spotted in 2010 within the Dinosaur Park Formation in Alberta, Canada. In 2013, paleontologists completely unearthed it, and this week, they have described what is undoubtedly a rare specimen."[32]
“For the first time ever, we have a complete skeleton of a baby ceratopsid.”[33]
"Only its forelimbs are completely missing."[32]
"The adult variants are certainly distinctive, with large openings in their head ornaments earning them their appropriate name, which literally means “opening lizard.” Fully grown, they reach a size of up to 4.8 meters (16 feet) and a weight of roughly 2 tonnes (2.2 tons)."[32]
"This juvenile Chasmosaurus is an adorable 1.5 meters (4.9 feet) in length, and would have weighed less than 100 kilograms (220 pounds). It’s so young that its vertebrae had not properly fused, its limbs were not fully articulated (joined up), and it had a particularly short snout. Due to its ornamental opening being fully enclosed by a single bone, scientists have deduced it is likely a species called Chasmosaurus belli."[32]
“We've only had a few isolated bones before to give us an idea of what these animals should look like as youngsters, but we've never had anything to connect all the pieces. All you need is one specimen that ties them all together. Now we have it!”[33]
Tylosaurus proriger is from the Santonian and lower to middle Campanian of North America (Kansas, Alabama, Nebraska, etc.).[34]
Santonian
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{{fairuse}}The specimen Hungarosaurus tormai designated as the holotype is MTM Gyn/404 (in the collections of the Magyar Természettudományi Múzeum, Budapest, Hungary) and consists of 450 bones, including portions of the skull (premaxilla, left prefrontal, left lacrimal, right postorbital, jugal and quadratojugal, left frontal, pterygoid, vomer, the right quadrate and a fragment of the left quadrate, basioccipital, one hyoid), an incomplete right mandible, three cervical vertebrae, six dorsal vertebrae, ten caudal vertebrae, ossified tendon fragments, three cerival and thirteen dorsal ribs, five chevrons, the left scapulocoracoid, right scapula, portions of the right manus, a partial pelvis, and more than one hundred osteoderms.[35]
The length of Hungarosaurus has been estimated at about 4 to 4.5 meters.[36]
The exposure of the Csehbánya Formation that produced Hungarosaurus tormai has also yielded remains of bony fishes, turtles, lizards, crocodiles, and pterosaurs, along with teeth from a diminutive dromaeosaurid-like theropod and a Rhabdodon-like ornithopod.[35]
The image in the center shows fossil pieces identified as a baby Tylosaurus.
Coniacian
- ↑ 97.127.8.250 (7 April 2018). Paleontology. San Francisco, California USA: Wikimedia Foundation, Inc. Retrieved 2018-04-12.
- ↑ paleontology, In: Wiktionary. San Francisco, California: Wikimedia Foundation, Inc. March 8, 2012. Retrieved 2012-07-22.
- ↑ Stephen Jay Gould, Norman L. Gilinsky and Rebecca Z. German (1987). "Asymmetry of lineages and the direction of evolutionary time" (PDF). Science. 236 (4807): 1437–41. doi:10.1126/science.236.4807.1437. Retrieved 2011-08-02. Unknown parameter
|month=ignored (help) - ↑ 4.0 4.1 fossil. San Francisco, California: Wikimedia Foundation, Inc. May 22, 2012. Retrieved 2012-07-22.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 Riley Black (May 21, 2019). "The Colors of Dinosaurs Open a New Window to Study the Past Old fossils and new technology are coloring in life's prehistoric palette". Smithsonian Magazine. Retrieved 28 May 2019.
- ↑ 6.0 6.1 Jakob Vinther (May 21, 2019). "The Colors of Dinosaurs Open a New Window to Study the Past Old fossils and new technology are coloring in life's prehistoric palette". Smithsonian Magazine. Retrieved 28 May 2019.
- ↑ 7.0 7.1 7.2 Caitlin Colleary (May 21, 2019). "The Colors of Dinosaurs Open a New Window to Study the Past Old fossils and new technology are coloring in life's prehistoric palette". Smithsonian Magazine. Retrieved 28 May 2019.
- ↑ stratigraphy.org. "International Commission on Stratigraphy 2008". Retrieved 9 March 2009.
- ↑ Barbara Wohlfarth (April 2010). "Ice-free conditions in Sweden during Marine Oxygen Isotope Stage 3?" (PDF). Boreas. 39: 377–98. doi:10.1111/j.1502-3885.2009.00137.x. Retrieved 2014-11-06.
- ↑ Andrei Valerievich Shpansky, Valentina Nurmagambetovna Aliyassova and Svetlana Anatolievna Ilyina (2016). "The Quaternary Mammals from Kozhamzhar Locality (Pavlodar Region, Kazakhstan)". American Journal of Applied Sciences. 13 (2): 189–199. doi:10.3844/ajassp.2016.189.199. Retrieved 28 November 2018.
- ↑ J. Vandenberghe and G. Nugteren (=2001). "Rapid climatic changes recorded in loess successions" (PDF). Global and Planetary Change. 28 (1–9): 222–30. Retrieved 2014-11-06. Check date values in:
|date=(help) - ↑ Pavel Kosintsev, Kieren J. Mitchell, Thibaut Devièse, Johannes van der Plicht, Margot Kuitems, Ekaterina Petrova, Alexei Tikhonov, Thomas Higham, Daniel Comeskey, Chris Turney, Alan Cooper, Thijs van Kolfschoten, Anthony J. Stuart & Adrian M. Lister (26 November 2018). "Evolution and extinction of the giant rhinoceros Elasmotherium sibiricum sheds light on late Quaternary megafaunal extinctions". Nature Ecology and Evolution. Retrieved 28 November 2018.
- ↑ 13.0 13.1 13.2 13.3 Sam Wong (11 January 2017). "Extinct giant goose used its wings to fight rather than fly". NewScientist. Retrieved 2017-01-13.
- ↑ 14.0 14.1 14.2 Julian Hume (11 January 2017). "Extinct giant goose used its wings to fight rather than fly". NewScientist. Retrieved 2017-01-13.
- ↑ 15.0 15.1 15.2 15.3 15.4 15.5 15.6 Trevor H. Worthy, Suzanne J. Hand, Michael Archer, R. Paul Scofield and Vanesa L. De Pietri (7 August 2019). "Evidence for a giant parrot from the Early Miocene of New Zealand". Biology Letters: 0467. doi:10.1098/rsbl.2019.0467. Retrieved 9 August 2019.
- ↑ 16.0 16.1 Gaidheal1 (April 13, 2011). "Paleogene Period, In: Wikiversity". Retrieved 2012-07-24.
- ↑ 17.0 17.1 17.2 17.3 Nobuaki Mizumoto (28 May 2019). "Fossil captures hundreds of ancient fish swimming as one". Nature. Retrieved 1 June 2019.
- ↑ Alexander Mudroch, Ute Richter, Ulrich Joger, Ralf Kosma, Oumarou Idé, Abdoulaye Maga (2011). "Didactyl Tracks of Paravian Theropods (Maniraptora) from the ?Middle Jurassic of Africa". PLoS ONE. 6 (2): e14642. doi:10.1371/journal.pone.0014642. PMID 21339816. Retrieved 2011-09-14. Unknown parameter
|month=ignored (help) - ↑ Gaidheal1 (May 16, 2012). Cretaceous Period. Retrieved 2012-07-24.
- ↑ David B. Weishampel; Barrett, P.M.; Coria, R.A.; Le Loueff, J.; Xu, X.; Zhao, X.; Sahni, A.; Gomani, E.M.P. & Noto, C.N. (2004). Weishampel, D.B.; Dodson, P. & Osmólska, H., ed. Dinosaur distribution, In: The Dinosauria. Berkeley (2nd ed.): University of California Press. pp. 517–606. ISBN 0-520-24209-2.
- ↑ Galton and Upchurch (2004); "Introduction", page 343.
- ↑ Wilton, Mark P. (2013). Pterosaurs: Natural History, Evolution, Anatomy. Princeton University Press. isbn=0691150613 }}
- ↑ Barrett, P. M., Butler, R. J., Edwards, N. P., & Milner, A. R. (2008). Pterosaur distribution in time and space: an atlas. Zitteliana: 61-107.[1]
- ↑ Carroll, N. REASSIGNMENT OF MONTANAZHDARCHO MINOR AS A NON-AZHDARCHID MEMBER OF THE AZHDARCHOIDEA, SVP 2015
- ↑ Federico L. Agnolin and David Varricchio (2012). "Systematic reinterpretation of Piksi barbarulna Varricchio, 2002 from the Two Medicine Formation (Upper Cretaceous) of Western USA (Montana) as a pterosaur rather than a bird" (PDF). Geodiversitas 34 (4): 883–894. doi:10.5252/g2012n4a10.
- ↑ Longrich, N.R., Martill, D.M., and Andres, B. (2018). Late Maastrichtian pterosaurs from North Africa and mass extinction of Pterosauria at the Cretaceous-Paleogene boundary. PLoS Biology, 16(3): e2001663. doi:10.1371/journal.pbio.2001663
- ↑ Dollo, L., 1891. La vie au sein des mers. Paris, Librairie J.B. Baillière et Fil
- ↑ Paulina Jimenez-huidobro and Michael W. Caldwell (2016). "Reassessment and reassignment of the early Maastrichtian mosasaur Hainosaurus bernardi Dollo, 1885, to Tylosaurus Marsh, 1872". Journal of Vertebrate Paleontology. Online edition: e1096275. doi:10.1080/02724634.2016.1096275.
- ↑ Lidmar-Bergström, Karna; Bonow, Johan M.; Japsen, Peter (2013). "Stratigraphic Landscape Analysis and geomorphological paradigms: Scandinavia as an example of Phanerozoic uplift and subsidence". Global and Planetary Change. 100: 153–171. doi:10.1016/j.gloplacha.2012.10.015.
- ↑ Surlyk, Finn; Sørensen, Anne Mehlin (2010). "An early Campanian rocky shore at Ivö Klack, southern Sweden". Cretaceous Research. 31: 567–576. doi:10.1016/j.cretres.2010.07.006.
- ↑ David B. Weishampel; Barrett, P.M.; Coria, R.A.; Le Loueff, J.; Xu, X.; Zhao, X.; Sahni, A.; Gomani, E.M.P. & Noto, C.N. (2004). Weishampel, D.B.; Dodson, P. & Osmólska, H., ed. Dinosaur distribution, In: The Dinosauria. Berkeley: University of California Press. pp. 517–606. ISBN 0-520-24209-2.
- ↑ 32.0 32.1 32.2 32.3 32.4 Robin Andrews (15 January 2016). Incredibly Preserved 75 Million-Year-Old Baby Dinosaur Discovered. iflscience. Retrieved 2016-01-16.
- ↑ 33.0 33.1 Philip Currie (15 January 2016). Incredibly Preserved 75 Million-Year-Old Baby Dinosaur Discovered. iflscience. Retrieved 2016-01-16.
- ↑ Cope ED. 1869. [Remarks on Macrosaurus proriger.] Proceedings of the Academy of Natural Sciences of Philadelphia 11(81): 123.
- ↑ 35.0 35.1 Ősi, Attila (2005). "Hungarosaurus tormai, a new ankylosaur (Dinosauria) from the Upper Cretaceous of Hungary." Journal of Vertebrate Paleontology '25 (2): 370-383
- ↑ Atilla Ősi, & E. Prondvai (2013). "Sympatry of two ankylosaurs (Hungarosaurus and cf. Struthiosaurus) in the Santonian of Hungary". Cretaceous Research. 44: 58-63.