WFS

Formation of sedimentary layers of white clay, Tamilnadu, India

Fossil site for wood fossils, Tamilnadu, India

Fossil site in Kerala, India

Fossil wood park maintained by geological survey of India at Tamilnadu

Cretaceous fossil sites india

Fossils in rack:-Cyad

Fossils in rack:-echiniderms

Fossils in rack:-Rastellum sp

Pre-historic seabed, Cretaceous period

WFS News: Morphological characteristics of preparator air-scribe marks: Implications for taphonomic research

November 3rd, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Morphological characteristics of preparator air-scribe marks: Implications for taphonomic research

Taphonomic analyses of bone-surface modifications can provide key insights into past biotic involvement with animal remains, as well as elucidate the context(s) of other biostratinomic (pre-burial) processes, diagenesis, excavation, preparation and storage. Such analyses, however, first require researchers to rigorously disambiguate between continuums of damage morphologies prior to attributing individual marks to specific actors and effectors (e.g., carnivore tooth, stone tool cutting edge, etc.). To date, a number of bone-modifying agents have been identified, and criteria for identifying their traces have been published. Relatively little research, however, has focused on bone-surface modifications imparted during specimen preparation. Herein we report that air scribes, small pneumatic tools commonly used for preparation in museum contexts, can generate unintentional marks that may mimic surficial modification caused by carnivores. To aid investigators in assessing the hypothesis that a mark in question is derived from air-scribe preparation activities, we provide high-resolution, detailed morphological information imaged with scanning electron microscopy (SEM). The main diagnostic characteristic of air-scribe damage is the occurrence of sequential, variously spaced, sub-millimeter scallop-like stepped bone removals. This morphology can resemble damage imparted by carnivore teeth. In contrast to marks produced by trampling, stone tools and carnivores, however, no continuous internal features, such as linear microstriations, were observed within grooves produced by the air scribe. Thus, the presence of such features can be used to disprove an air-scribe origin. A culmination of the morphological criteria presented herein, cross-cutting relationships with other surficial features (e.g., diagenetic discoloration, weathering textures), the position of occurrence, and an overall contextual framework for the assemblage is suggested for accurate identification of such traces. The ability to recognize or disprove air-scribe damage will allow researchers to confidently proceed with interpreting past biological and sedimentological interactions with animal remains.

Comparison of carnivore-induced tooth scores (left column) and air-scribe-induced grooves (right column) under SEM.
Insets are interpretive drawings of highlighted areas. A) Segment of a smooth tooth score with relatively smooth margins and faint, internal grooves exhibiting continuity on a bovid long bone; scale bar = 0.5 mm. B) Segment of a transition within an air-scribe groove from a chatter-like morphology (upper half) into a smooth-based groove on a fossilized bone fragment; scale bar = 1.0 mm; Notice the rougher margins in comparison to A. C) Shallow tooth score with chatter marks, a smooth left margin, and an irregular right margin on a bovid long bone; scale bar = 1.0 mm. D) shallow (lower left) and deep (top to bottom) air-scribe grooves on a fossilized bone fragment; scale bar = 1.0 mm. Notice the similarities between the chatter morphology of the lower-left mark and the scores depicted in C and E. Also note the relatively rougher margins. E) Tooth score with pronounced chatter markings and a long-axis-parallel, smooth left shoulder with through-going continuity on a bovid long bone; scale bar = 1.0 mm. F) sinuous air-scribe groove with faint chatter marks, rough margins, and an absence of through-going continuity on a fragment of a chelonian carapace; scale bar = 1.0 mm.

Citation: Wiest LA, Ferraro JV, Binetti KM, Forman SL, Esker DA, Kibunjia M, et al. (2018) Morphological characteristics of preparator air-scribe marks: Implications for taphonomic research. PLoS ONE 13(12): e0209330. https://doi.org/10.1371/journal.pone.0209330

Editor: Cyril Charles, Ecole Normale Supérieure de Lyon, FRANCE

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Fossil shows trilobites go marching one by one

November 2nd, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Trilobites of the species Ampx priscus were caught in an avalanche of sediment 480 million years ago as they marched in a single-file line on the seafloor of what is now Morocco.
(Image: © Jean Vannier)

The trilobites go marching one by one, hurrah, hurrah … well, at least they did, some 480 million years ago.

New fossils from Morocco show lines of trilobites in orderly queues, likely buried by a storm as they trekked from one place to another under the Ordovician seas in an ancient game of “follow the leader.”

“I think people think that collective behavior is something new in the course of evolution, but actually sophisticated behavior started very, very early,” said study leader Jean Vannier, a paleontologist at the University of Lyon in France.

Trilobites all in a row

Vannier and colleagues from Marrakech, Morocco, discovered the trilobites in the southern part of Morocco in an area known for well-preserved fossils of animals from the early Ordovician, a geologic period that began about 485 million years ago and is one of six periods that make up the Paleozoic era. The Ordovician is famous for its diverse marine life, from primitive fish to corals to undersea scorpions the size of human beings. Trilobites — arthropods that looked a bit like cockroaches — also scuttled around the Ordovician seafloor or swam through its oceans. These resilient creatures first evolved during the period before the Ordivician, the Cambrian, and survived two mass extinctions (one at the end of the Ordovician, about 444 million years ago, and one at the end of the Devonian, about 360 million years ago). Trilobites didn’t disappear until 252 million years ago, when a mass extinction at the end of the Permian period wiped out 95% of all species on Earth.

The trilobites were blind, so they may have used their spiny body projections to keep in touch with one another as they moved along in a queue.(Image credit: Jean Vannier)

Not much is known about how trilobites behaved, but some fossil evidence hints that they didn’t swim or burrow solo. Paleontologists have found clusters of fossilized trilobites, apparently gathered in large groups to molt their exoskeletons or to mate. The new Moroccan fossils were striking because the trilobites were cleanly arranged in lines and obviously hadn’t floated into position after death, Vannier said: The animals were all facing the same direction, often touching each other with the spiny projections from their bodies. Their single-file arrangement is reminiscent of the migration of the modern-day spiny lobster, Vannier told Live Science. These Caribbean creatures queue up in lines to march to quiet waters during stormy months, resting their antennae on one another as they move.

Acting collectively

The rocks around the trilobite fossils showed evidence of repeated, rapid storm deposits, Vannier and his colleagues reported today (Oct. 17) in the journal Scientific Reports. The lined-up trilobites were probably buried instantly by an avalanche of sediment, possibly accompanied by the stirring-up of oxygen-poor waters that helped suffocate the animals rapidly. The fossils record no sign of a struggle in death; whatever took their lives didn’t even disrupt the trilobites’ careful queue.

These trilobite queues reveal collective behavior in very early animals, reminiscent of the modern-day mass migrations of Caribbean spiny lobsters.(Image credit: Jean Vannier)

Similar trilobite queuing has been found fossilized in younger rocks, Vannier said, and fossils from southern France show the same species (Ampyx priscus) lined up. The trilobites were blind, so they may have used their projecting spines to keep track of each other as they moved.

“It seems to be a normal behavior of this species in different parts of the world,” Vannier said.

Trilobites aren’t the only ancient animals that seem to have behaved collectively. Shrimp-like creatures called Synophalos from the Cambrian period 520 million years ago have been found fossilized in long chains in China. Scientists suspect they were migrating as a group. And horseshoe crabs, which first appeared on the scene 450 million years ago, still gather on shorelines today to breed under the cover of darkness.

Source: Article By Stephanie Pappas – Live Science

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News:

October 25th, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Rapid ocean acidification and protracted Earth system recovery followed the end-Cretaceous Chicxulub impact

Debate lingers over what caused the last mass extinction 66 million years ago, with intense volcanism and extraterrestrial impact the most widely supported hypotheses. However, without empirical evidence for either’s exact environmental effects, it is difficult to discern which was most important in driving extinction. It is also unclear why recovery of biodiversity and carbon cycling in the oceans was so slow after an apparently sudden extinction event. In this paper, we show (using boron isotopes and Earth system modeling) that the impact caused rapid ocean acidification, and that the resulting ecological collapse in the oceans had long-lasting effects for global carbon cycling and climate. Our data suggest that impact, not volcanism, was key in driving end-Cretaceous mass extinction.

Mass extinction at the Cretaceous–Paleogene (K-Pg) boundary coincides with the Chicxulub bolide impact and also falls within the broader time frame of Deccan trap emplacement. Critically, though, empirical evidence as to how either of these factors could have driven observed extinction patterns and carbon cycle perturbations is still lacking. Here, using boron isotopes in foraminifera, we document a geologically rapid surface-ocean pH drop following the Chicxulub impact, supporting impact-induced ocean acidification as a mechanism for ecological collapse in the marine realm. Subsequently, surface water pH rebounded sharply with the extinction of marine calcifiers and the associated imbalance in the global carbon cycle. Our reconstructed water-column pH gradients, combined with Earth system modeling, indicate that a partial ∼50% reduction in global marine primary productivity is sufficient to explain observed marine carbon isotope patterns at the K-Pg, due to the underlying action of the solubility pump. While primary productivity recovered within a few tens of thousands of years, inefficiency in carbon export to the deep sea lasted much longer. This phased recovery scenario reconciles competing hypotheses previously put forward to explain the K-Pg carbon isotope records, and explains both spatially variable patterns of change in marine productivity across the event and a lack of extinction at the deep sea floor. In sum, we provide insights into the drivers of the last mass extinction, the recovery of marine carbon cycling in a postextinction world, and the way in which marine life imprints its isotopic signal onto the geological record.

Records of surface ocean foraminiferal δ11B (B), calculated pH (C), and pCO2 (D) across the K-Pg boundary, with high-resolution foraminiferal diversity counts from ref. 39 at the K-Pg Global Boundary Stratotype Section and Point (El Kef) plotted for context (A). pH is calculated assuming our best estimate of K-Pg δ11Bsw, 39.45 ± 0.4‰. pCO2 is calculated from pH along with total alkalinity estimates at each site from a GENIE late Maastrichtian simulation, adjusted for dynamic changes in alkalinity across the K-Pg using LOSCAR simulations from ref. 22 that match observed patterns of carbonate burial. Gray shaded areas are 1-sigma uncertainties, with thin lines representing 1,000 Monte Carlo simulations from the 10,000 that were run. For clarity, we only plot those samples that represent the surface mixed layer, which should be approximately in equilibrium with the atmosphere. Additional data from deep-sea benthic and thermocline-dwelling planktic foraminifera that do not reflect atmospheric pCO2 can be seen in Fig. 2 and in Dataset S1. For details of the age models used, the estimation of δ11Bsw, carbonate system calculations, and uncertainty propagation see SI Appendix.

Source: Rapid ocean acidification and protracted Earth system recovery followed the end-Cretaceous Chicxulub impact

WFS News: Jinguofortis perplexus,New Species of Dinosaur-Era Bird

October 22nd, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Paleontologists in China have discovered a new species of fossil bird that they say reveals a pivotal point in the evolution of flight, when birds had lost the long bony tail seen in dinosaurs such as Tyrannosaurus and the early bird Archaeopteryx, but before they had developed the fan of feathers on a shortened tail seen in flying birds today.

The 127-million-year-old species, which they have named Jinguofortis perplexus, retains other features of its dinosaur ancestors, such as claws on the fingers of its wings, a jaw with tiny teeth rather than a beak, and a fused shoulder girdle. That last trait is seemingly poorly adapted to flight, hence the name “perplexus.”

Discovered in the northeastern Chinese province of Hebei, Jinguofortis lived in a dense forested environment with scattered lakes, which characterized this region during the early Cretaceous. About the size of a modern crow, the species had wide, short wings that may have aided maneuverability between the trees.

“Generally, we think of the modern flight apparatus of living birds as having evolved through the gradual accumulation of refinements to their feathers, muscles, and bones over millions of years,” says Min Wang at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Science in Beijing, whose team describes the fossil this week in the journal PNAS.

“However,” Wang says, “this new bird fossil shows that the evolution of flight was much more messy.” (See a baby bird from the age of dinosaurs found preserved in amber.)

Fused Shoulder Bone

Jinguofortis is “one of the most important fossil birds found in recent years,” according to Steve Brusatte, a paleontologist at the University of Edinburgh in the U.K. who was one of the reviewing editors of the paper.

But perhaps the most interesting aspect of the fossil is the shoulder girdle, the experts say, which resembles that of non-avian dinosaurs rather than birds. Modern birds usually have two bones, the scapula and coracoid, that allow flexibility for flapping flight. But Jinguofortis’ shoulder is fused into a single bone, the scapulocoracoid.

This would be a “very unusual feature” in a flying bird, says Gerald Mayr, an ornithologist and expert on the evolution of birds at the Senckenberg Research Institute in Frankfurt, Germany. The two bones usually form a mobile joint that’s important for muscle and wing movement during flight.

“If this condition is confirmed in future studies, it may inspire new ideas on how these early birds used their wings,” Mayr says, since the feature would likely have impeded flapping flight. However, Mayr adds, the flight feathers of Jinguofortis look unusually narrow for a flying bird, and fused shoulder joints are common in flightless species, such as ostriches and rheas.

“One may therefore ask whether this animal was indeed capable of flight, or whether it may be an example of a flightless Mesozoic bird,” he says.

The fused shoulder girdle did prompt the team to consider that possibility, Wang says, but he argues that the wings and many other features of the fossil are nevertheless “indicative of refined flight capability.”

He believes this strange mix of features is instead evidence that the evolution of birds is more complicated than previously thought, with early species displaying a variety of ways of growing their skeletons and using their flight apparatus.

WFS News: A new carcharodontosaurian theropod (Dinosauria: Saurischia) from the Lower Cretaceous of Thailand

October 15th, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

A new carcharodontosaurian theropod (Dinosauria: Saurischia) from the Lower Cretaceous of Thailand

Skeletal reconstruction of Siamraptor suwati.Cranial elements were scaled to fit in with the holotype (surangular). Scale bar equals 1

Fossils discovered in Thailand represent a new genus and species of predatory dinosaur, according to a study released October 9, 2019 in the open-access journal PLOS ONE by Duangsuda Chokchaloemwong of Nakhon Ratchasima Rajabhat University, Thailand and colleagues.

Right premaxillae, NRRU-F01020003 (A–G), F01020002 (H–K) and F01020001 (L, M) in anterior (A), dorsal (B), medial (C, D, H, L), posterior (E), lateral (F, G, K, M) and alveolar (I) views. The rectangle in H indicates the area magnified in J to show premaxillary teeth. Abbreviations: ac, alveolar channel; en, external naris; fo, foramen; mp, maxillary process; nfo, nasal fossa; pa, possible pathology; snf, subnarial fossa; t, tooth. Scale bar equals 50 mm.

Carcharodontosaurs were a widespread and successful group of large predatory dinosaurs during the Jurassic and Cretaceous Periods and were important members of ecosystems on multiple continents. However, the fossil record of these animals is notably lacking from the Early Cretaceous of Asia, with no definite carcharodontosaurs known from Southeast Asia.

Dorsal vertebrae NRRU-F01020014 (A–D), F01020015 (E, F), and F01020016 (G, H) and a caudal vertebra NRRU-F01020017 (I–M) in posterior (A, F, L), right lateral (B, E), anterior (C, G, J), left lateral (H, K), dorsal (I), and ventral (F) views. Abbreviations: cc, chevron contact; cdf; centrodiapophyseal fossa; cprl, centroprezygapophyseal lamina; fo, foramen; hpa, hypantrum; hpo, hyposphene; mr, median ridge; ms, metaplastic scars; nc, neural canal; ns, neural spine; pcdf, prezygocentrodiapophyseal fossa; pocdf, postzygocentrodiapophyseal fossa; pnf, pneumatic foramen; poz, postzygapophysis; prz, prezygapophysis; spof, spinopostzygapophyseal fossa; sprf, spinoprezygapophyseal fossa; tp, transverse process. Scale bar equals 100 mm for A–H and 60 mm for I–M.
https://doi.org/10.1371/journal.pone.0222489.g010

In this study, Chokchaloemwong and colleagues describe fossil material from the Khok Kruat geologic formation in Khorat, Thailand, dating to the Early Cretaceous. These fossils include remains of the skull, backbone, limbs, and hips of at least four individual dinosaurs, and morphological comparison with known species led the authors to identify these remains as belonging to a previously unknown genus and species of carcharodontosaur which they named Siamraptor suwati.

Phylogenetic analysis indicates that Siamraptor is a basal member of the carcharodontosaurs, meaning it represents a very early evolutionary split from the rest of the group. It is also the first definitive carcharodontosaur known from Southeast Asia, and combined with similarly-aged finds from Europe and Africa, it reveals that this group of dinosaurs had already spread to three continents by the Early Cretaceous.

Ref: Duangsuda Chokchaloemwong, Soki Hattori, Elena Cuesta, Pratueng Jintasakul, Masateru Shibata, Yoichi Azuma. A new carcharodontosaurian theropod (Dinosauria: Saurischia) from the Lower Cretaceous of Thailand. PLOS ONE, 2019; 14 (10): e0222489 DOI: 10.1371/journal.pone.0222489

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: The anatomy of a crushing bite: The specialised cranial mechanics of a giant extinct kangaroo.

October 6th, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

An in-depth analysis of the skull biomechanics of a giant extinct kangaroo indicates that the animal had a capacity for high-performance crushing of foods, suggesting feeding behaviors more similar to a giant panda than modern-day kangaroo.

The new findings, published in PLOS ONE, support the hypothesis that some short-faced kangaroos were capable of persisting on tough, poor-quality vegetation, when more desirable foods were scarce because of droughts or glacial periods.

“The skull of the extinct kangaroo studied here differs from those of today’s kangaroos in many of the ways a giant panda’s skull differs from other bears,” said Rex Mitchell, post-doctoral fellow in the Department of Anthropology at the University of Arkansas. “So, it seems that the strange skull of this kangaroo was, in a functional sense, less like a modern-day kangaroo’s and more like a giant panda’s.”

Mitchell used computed tomography scans to create three-dimensional models of the skull of Simosthenurus occidentalis, a well-represented species of short-faced kangaroo that persisted until about 42,000 years ago. Working with the models, Mitchell performed bite simulations to examine biomechanical performance. The resulting forces at the jaw joints and biting teeth were measured, as well as stress experienced across the skull during biting.

Mitchell compared the findings from the short-faced kangaroo to those obtained from models of the koala, a species alive today with the most similar skull shape. These comparisons demonstrated the importance of the extinct kangaroo’s bony, heavily reinforced skull features in producing and withstanding strong forces during biting, which likely helped the animal crush thick, resistant vegetation such as the older leaves, woody twigs and branches of trees and shrubs. This would be quite different than the feeding habits of modern Australian kangaroos, which tend to feed mostly on grasses, and would instead be more similar to how giant pandas crush bamboo.

“Compared to the kangaroos of today, the extinct, short-faced kangaroos of ice age Australia would be a strange sight to behold,” Mitchell said.

They included the largest kangaroo species ever discovered, with some species estimated to weigh more than 400 pounds. The bodies of these kangaroos were much more robust than those of today — which top out at about 150 pounds — with long muscular arms and large heads shaped like a koala’s. Their short face offered increased mechanical efficiency during biting, a feature usually found in species that can bite harder into more resistant foods. Some species of these extinct kangaroos had massive skulls, with enormous cheek bones and wide foreheads.

“All this bone would have taken a lot of energy to produce and maintain, so it makes sense that such robust skulls wouldn’t have evolved unless they really needed to bite hard into at least some more resistant foods that were important in their diets,” Mitchell said.

The short face, large teeth, and broad attachment sites for biting muscles found in the skulls of the short-faced kangaroo and the giant panda are an example of convergent evolution, Mitchell said, meaning these features probably evolved in both animals for the purpose of performing similar feeding tasks.

Mitchell is also affiliated with the University of New England in Armidale, Australia, where he performed the analyses during his doctoral studies.

Journal Reference:

D. Rex Mitchell. The anatomy of a crushing bite: The specialised cranial mechanics of a giant extinct kangaroo. PLOS ONE, 2019; 14 (9): e0221287 DOI: 10.1371/journal.pone.0221287

University of Arkansas. “Crushing bite of giant kangaroos of ice age Australia.” ScienceDaily. ScienceDaily, 11 September 2019. <www.sciencedaily.com/releases/2019/09/190911142844.htm>.

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Fossil Stingrays (Myliobatiformes) gives new insights into evolution after end-Cretaceous mass extinction

October 3rd, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

An international research team led by Giuseppe Marramà from the Institute of Paleontology of the University of Vienna discovered a new and well-preserved fossil stingray with an exceptional anatomy, which greatly differs from living species. The find provides new insights into the evolution of these animals and sheds light on the recovery of marine ecosystems after the mass extinction occurred 66 million years ago. The study was recently published in the journal Scientific Reports.

Stingrays (Myliobatiformes) are a very diverse group of cartilaginous fishes which are known for their venomous and serrated tail stings, which they use against other predatory fish, and occasionally against humans. These rays have a rounded or wing-like pectoral disc and a long, whip-like tail that carries one or more serrated and venomous stings. The stingrays include the biggest rays of the world like the gigantic manta rays, which can reach a “wingspan” of up to seven meters and a weight of about three tons.

Fossil remains of stingrays are very common, especially their isolated teeth. Complete skeletons, however, exist only from a few extinct species coming from particular fossiliferous sites. Among these, Monte Bolca, in northeastern Italy, is one of the best known. So far, more than 230 species of fishes have been discovered that document a tropical marine coastal environment associated with coral reefs which dates back to about 50 million years ago in the period called Eocene.

This new fossil stingray has a flattened body and a pectoral disc ovoid in shape. What is striking is the absence of sting and the extremely short tail, which is not long as in the other stingrays, and does not protrude posteriorly to the disc. This body plan is not known in any other fossil or living stingray. Since this animal is unique and peculiar, the researchers named the new stingray Lessiniabatis aenigmatica, which means “bizarre ray from Lessinia” (the Italian area where Bolca is located).

More than 70 percent of the organisms, such as dinosaurs, marine reptiles, several mammal groups, numerous birds, fish and invertebrates, disappeared during the fifth largest extinction event in the Earth’s history occurred about 66 million years ago at the end of the Cretaceous. In marine environments, the time after this event is characterized by the emergence and diversification of new species and entire groups of bony and cartilaginous fishes (sharks and rays), which reoccupied the ecological niches left vacant by the extinction’s victims. The new species experimented sometimes new body plans and new ecological strategies.

“From this perspective, the emergence of a new body plan in a 50-million-year-old stingray such as Lessiniabatis aenigmatica is particularly intriguing when viewed in the context of simultaneous, extensive diversification and emergence of new anatomical features within several fish groups, during the recovery of the life after the end-Cretaceous extinction event,” states Giuseppe Marramà.

Giuseppe Marramà, Giorgio Carnevale, Luca Giusberti, Gavin J. P. Naylor, Jürgen Kriwet. A bizarre Eocene dasyatoid batomorph (Elasmobranchii, Myliobatiformes) from the Bolca Lagerstätte (Italy) reveals a new, extinct body plan for stingrays. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-019-50544-y

Source: Sciencedaily.com

WFS News: Unusual fossil marine invertebrate has been uncovered

September 21st, 2019

Riffin

@ WFS,World Fossil Society, Riffin T Sajeev,Russel T Sajeev

A species of wormlike marine invertebrate has been uncovered.

The animals are fossil echinoderms from the Silurian Period, making them about 435 million years old. Now extinct, they are distant relatives of starfish and sea cucumbers.

They were found after researchers discovered a group of well-preserved fossils from Anticosti Island in Quebec, Canada. An investigation revealed that the fossils are a newly described species, now named Rhenopyrgus viviani.

Discoveries like this allow us to understand more about how life on Earth has evolved. The Silurian Period was about 200 million years before the first dinosaurs, and it saw the first plants and animals emerge onto land.

Researchers still have a lot to learn about the organisms that flourished during this period of Earth’s history.

Photographs of the specimens in the study (left) and a reconstruction of how the extinct animals could have looked (right)

Museum curator Dr Tim Ewin, who led the research team for this study, says, ‘A big part of understanding early life is simply knowing what that life looked like and how it behaved. Being able to accurately reconstruct an animal gives us valuable insights into how it lived and in cases, such as this, they can prove to be quite unique in appearance and have surprising behaviour.

‘By expanding our knowledge of how animals in the past lived and evolved we can better understand why they became extinct and so protect the biodiversity of our planet today.’

It was previously thought that these animals lived in burrows and were able to bury themselves in sediment and hide away.

But Dr Ewin thinks they were actually bottom-dwelling ‘mud-stickers’ that stood erect.

The animals were supported by the insertion of a bulbous, sac-like structure at the base of the stem into a muddy sea floor. They were only able contract a small part of the top of the stem, to protect important openings such as the anus.

Dr Ewin continues, ‘Rather than living in mud burrows, we now believe these creatures protruded from the sea floor, displaying a degree of flexibility.

‘This allowed them to place their mouth higher up into the water column to feed. It is remarkable how new fossil evidence can alter our perceptions of ancient life.’

The new paper also identified greater diversity in the construction of the mouth of rhenopyrgids (a type of edrioasteroid) than previously thought.

This diversity of form has also been seen in other stalked edrioasteroids suggesting convergent evolution of these adaptations.

Source: Natural History Museum.UK

@ WFS,World Fossil Society, Riffin T Sajeev,Russel T Sajeev

WFS News: Fossilized hair is rare,Why?

September 20th, 2019

Riffin

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

When most people hear the word fossil, they probably think of gigantic leg bones or sharp teeth. But, given the right conditions, after an animal dies even delicate body coverings like skin, hair and feathers can be preserved.

New research led by The University of Texas at Austin has found that when it comes to preserving these body parts, fossilized hair is rare — five times rarer than feathers — despite being an important tool for understanding ancient species. This finding has researchers trying to determine if the lack of hair in the fossil record has to do with physical traits that might make it more difficult for hair to fossilize, or an issue with scientists’ collection techniques that could lead to them missing important finds.

“This pattern of where and when we do find fossilized feathers and hairs can be used to inform where we look for future fossil discoveries,” said first author Chad Eliason, a researcher at the Field Museum of Natural History who conducted the research while a postdoctoral fellow at the UT Jackson School of Geosciences.

Distribution of tetrapod Konservat-Lagerstätten through time and space (n = 143). (a) Numbers of Lagerstätten found in fluvial (light green), lacustrine (medium green), near-shore marine (blue) and other terrestrial depositional environments (dark green) are shown on the y-axis by period as well as epoch (for the Mesozoic and Cenozoic). For all statistical analyses, we used 10 My time bins after assessing the influence of time bin size on our statistical results (see electronic supplementary material, figure S7). (b) Global distribution of Lagerstätten found in different depositional environments. Pies show relative numbers in different depositional environments (colours of pie) and absolute number per country (size of pie). (c) Earliest skin impressions in Saurerpeton [49]. (d) Earliest putative filaments in Eudimorphodon rosenfeldi [50]. (e) Scales in the ornithischian dinosaur Kulindadromeus zabaikalicus [24]. (f) Earliest known feathers in Anchiornis huxleyi [51]. (g) Earliest preserved hair in Rugosodon eurasiaticus [52]. Image credits: (c) Smokeybjb (CC BY-SA 3.0), (d) Tommy from Arad (CC BY 2.0), (e) Tomopteryx (CC BY-SA 4.0), (f) Kumiko (CC BY-SA 2.0), (g) Zhe-Xi Luo (University of Chicago). (Online version in colour.)

The study was published on Sept. 6 in the journal Proceedings of the Royal Society B. Co-authors include Julia Clarke, a professor in the Jackson School’s Department of Geological Sciences who led the study, and three Jackson School undergraduate students, Leah Hudson, Taylor Watts and Hector Garza.Fossils of body coverings contain unique data on the ecology and lifestyle of extinct animals, including what color they might have been. They also might affect our understanding of when kinds of body coverings, such as feathers and hair, evolved. In this study, the researchers used data on fossil type and age to determine that hair probably evolved much earlier than current fossil samples indicate.

Fossil beds that preserve soft tissues like hair and feathers are called lagerstatte (‘fossil storehouses’ in German) and are rare on their own. The researchers were interested in understanding how frequently different types of body coverings were found preserved in these exceptional sites, which include the Yixian Formation in China and the Green River Formation in the western United States.

Eliason and his collaborators assembled the largest known database of fossilized body coverings, or integument, from land-dwelling vertebrates, a group known as tetrapods, collected from lagerstatte. They found that unlike feathers, hairs are extremely rare finds.

“Mammal hair has been around for more than 160 million years yet over that time we have very few records,” Eliason said.

The rarity might be explained by feathers and hair containing different types of the protein keratin, which may impact the likelihood of fossilization. However, the study notes that the lack of hair samples could have nothing to do with fossilization, and be explained by the collecting behavior of paleontologists, with a single feather usually being much easier to identify than a single hair.

The database also allowed the researchers to conduct a type of statistical method called gap analysis, which models the probability of finding a fossil in a given time. The team found that feathers appear to have evolved very close to the earliest known examples in the fossil record, about 165 million years ago. However, hair and hair-like filaments found on pterosaurs probably evolved far earlier in the fossil record than currently known.

“The hunt is on,” said Clarke. “These data suggest we might expect to find records up to 100 million years earlier potentially.”

The team also applied a statistical approach called a time series analyses to study if climatic factors might explain gaps in the fossil record. They found that soft tissue preservation was most common when ancient sea levels were high.

“There is still a lot we don’t know about the chemistry of these deposits and why they are so uneven through time,” Clarke said. “But we can say that their uneven distribution across the world — most [sites] are in North America or Eurasia — is an artifact of where paleontologists looked. We have a lot more work to do.”

Chad M. Eliason, Leah Hudson, Taylor Watts, Hector Garza, Julia A. Clarke. Exceptional preservation and the fossil record of tetrapod integument. Proceedings of the Royal Society B: Biological Sciences, 2017; 284 (1862): 20170556 DOI: 10.1098/rspb.2017.0556

Source: Science daily.com

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WFS News: Heracles inexpectatus : Giant bird lived in New Zealand around 19 MYA

September 14th, 2019

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@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Imagine a parrot standing 3 feet (1 meter) tall, about the height of a 2-year-old child. This giant bird lived in New Zealand around 19 million years ago; it was the largest parrot that ever lived, and is the only known giant parrot in the world.

Paleontologists recently described the gargantuan bird from a pair of fossilized leg bones found at a fossil-rich site in St. Bathans, New Zealand. The bones were “large and robust,” and in life the bird may have weighed up to 15 pounds (7 kilograms), the researchers reported in a new study.

A reconstruction of the giant parrot Heracles shows how the massive bird would have dwarfed the small New Zealand wren called Kuiornis.(Image: © Illustration by Brian Choo, Flinders University)

They named the bird Heracles inexpectatus: “Heracles” is a nod to the mythic Greek hero, also known as “Hercules.” The species name “inexpectatus” addresses how unexpected it was for the researchers to discover this previously unknown colossus.

New Zealand is known for other types of extinct giant birds that once stalked its forests and grasslands and soared in its skies. The massive, flightless moa (Dinornis robustus) stood as tall as 6 feet (2 m) at the shoulder and weighed up to 530 lbs. (240 kilograms), while the Haast’s eagle (Hieraaetus moorei) — the largest known eagle of all time — had a wingspan of about 10 feet (3 m) and weighed up to 26 lbs. (12 kg).

Scientists discovered the parrot leg bones in 2008; for years, they hunted for more fossils of the animal, but further evidence remained frustratingly elusive, said lead study author Trevor Worthy, an associate professor with the College of Science and Engineering at Flinders University in Australia.

“Ten years on and thousands of bones later, no more has come to light. So we decided, well, we need to tell this story now,” Worthy told Live Science in an email.

The bones were solid and thick-walled, suggesting Heracles wouldn’t have been able to fly. However, it may have been able to climb trees and glide like the modern kakapo (Strigops habroptilus), a large parrot that is also native to New Zealand, Worthy said. Kakapos are currently the biggest parrots in the world, but Heracles was easily twice as massive as its pudgy, flightless cousins.

“It lived in a subtropical rainforest where there were abundant laurels, palms, cycads and casuarina trees — all produce fruit and seeds that this parrot would have eaten,” Worthy said. Heracles likely dominated this niche on the forest floor, which could explain why the species evolved to be so much bigger than other parrots.

Graphic showing the Heracles inexpectatus silhouette next to an average-height person and a common magpie.(Image credit: Paul Scofield, Canterbury Museum)

What ended the reign of these mighty birds? The culprit was probably climate change, Worthy said. Around 12 million to 13 million years ago, global temperatures plummeted; over time, New Zealand’s tropical forests became temperate forests, greatly reducing the number of fruit trees across the island.

The disappearance of Heracles’ main food source “would be a major candidate for causing this bird to go extinct,” Worthy said.

The findings were published online today (Aug. 6) in the journal Biology Letters.

Source: Live Science

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev