WFS News: X-raying the Earth with waves from stormy weather ‘bombs’

Using a detection network based in Japan, scientists have uncovered a rare type of deep-earth tremor that they attribute to a distant North Atlantic storm called a “weather bomb.”

The discovery marks the first time scientists have observed this particular tremor, known as an S wave microseism. And, as Peter Gerstoft and Peter D. Bromirski write in a related Perspective, their observation “gives seismologists a new tool with which to study Earth’s deeper structure,” one that will contribute to a clearer picture of Earth’s movements, even those originating from the atmosphere-ocean system.

An Atlantic "weather bomb," or a severe, fast-developing storm, causes ocean swells that incite faint and deep tremors into the oceanic crust. These subtle waves run through the earth and can be detected in places as far away as Japan, where facilities using a method called "Hi-net" measure the amplitude of the storm's P and S waves for the first time. Credit: Kiwamu Nishida and Ryota Takagi

An Atlantic “weather bomb,” or a severe, fast-developing storm, causes ocean swells that incite faint and deep tremors into the oceanic crust. These subtle waves run through the earth and can be detected in places as far away as Japan, where facilities using a method called “Hi-net” measure the amplitude of the storm’s P and S waves for the first time.Credit: Kiwamu Nishida and Ryota Takagi

Faint tremors called microseisms are phenomena caused by the sloshing of the ocean’s waves on the solid Earth floor during storms. Detectable anywhere in the world, microseisms can be various waveforms that move through the Earth’s surface and interior, respectively.

So far, however, scientists analyzing microseismic activity in the Earth have only been able to chart P waves (those that animals can feel before an earthquake), and not their more elusive S wave counterpart (those that humans feel during earthquakes).

Here, using 202 Hi-net stations operated by the National Research Institute for Earth Science and Disaster Prevention in Japan’s Chugoku district, Kiwamu Nishida and Ryota Takagi successfully detected not only P wave microseisms triggered by a severe and distant North Atlantic storm, known as a weather bomb, but also S wave microseisms, too.

What’s more, the authors determined both the direction and distance to these waves’ origins, providing insight into their paths as well as the earthly structures through which they traveled. In this way, the seismic energy travelling from this weather bomb storm through the Earth illuminated many dark patches of its interior. Nishida and Takagi’s findings not only offer a new means by which to explore the Earth’s internal structure, but they may also contribute to more accurate detection of earthquakes and oceanic storms.

Citation: American Association for the Advancement of Science. “X-raying the Earth with waves from stormy weather ‘bombs’.” ScienceDaily. ScienceDaily, 25 August 2016. <www.sciencedaily.com/releases/2016/08/160825151609.htm

KeY: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Beetles with Orchid Pollinaria in Dominican and Mexican Amber

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

Beetles with Orchid Pollinaria in Dominican and Mexican Amber

Orchids are extraordinary plants that have evolved the strategy of dispersing their pollen in little sacs called pollinia. Pollinia are normally attached by supports (caudicles) to adhesive pads (viscidia) that stick to various body parts of the pollinator. The entire pollination unit is called a pollinarium. Since pollen dispensed in pollinia is not available as food to most insects (van der Cingel 1995), orchids supply nectar or have evolved ingenious patterns of mimicry and deceit to attract potential pollinators (Endress 1994).

Dominican amber cryptorhynchid weevil with attached pollinarium (arrow) of Cylindrocites browni gen. n., sp. n. Floral remains in background. Scale = 3.0 mm.

Dominican amber cryptorhynchid weevil with attached pollinarium (arrow) of Cylindrocites browni gen. n., sp. n. Floral remains in background. Scale = 3.0 mm. @WFS News

Beetle associations with orchids are diverse. Beetles may visit orchid flowers simply for nectar, or at the same time acquire pollinaria and serve as pollinators. Beetles can also feed and raise their brood on orchid floral and vegetative parts. Some orchids depend on various Coleoptera for pollination and have produced “cantharophilous” flowers especially attractive to beetles (Endress 1994, Kalshoven and van der Laan 1981).

Lateral view of weevil with attached pollinarium of Cylindrocites browni gen. n., sp. n. Arrow shows viscidium. Scale = 0.8 mm.

Lateral view of weevil with attached pollinarium of Cylindrocites browni gen. n., sp. n. Arrow shows viscidium. Scale = 0.8 mm. @WFS News

The present study provides the first fossil evidence of beetles serving as pollinators of orchids. The two examples consist of a cryptorhynchine weevil (Coleoptera: Curculionidae) in Dominican amber with an orchid pollinaria attached to its thorax and a ptilodactyline beetle (Coleoptera: Ptilodactylidae) in Mexican amber with a pollinarium adhering to its mouthparts. These pollinaria are described below and associations between beetles and orchids are reviewed.

Lateral view of pollinarium of Cylindrocites browni gen. n., sp. n. attached to weevil. V = viscidium. Top arrow shows mucoid connection between viscidium and weevil. Bar = 0.4 mm. Insert shows pollen tetrads (arrow) inside pollinium. Scale = 60 μm.

Lateral view of pollinarium of Cylindrocites browni gen. n., sp. n. attached to weevil. V = viscidium. Top arrow shows mucoid connection between viscidium and weevil. Bar = 0.4 mm. Insert shows pollen tetrads (arrow) inside pollinium. Scale = 60 μm.@WFS News

Materials and methods

The Dominican amber specimen was obtained from mines located in the Cordillera Septentrional of the Dominican Republic. These mines are in the Altimira facies of the El Mamey formation, which is shale-sandstone interspersed with a conglomerate of well-rounded pebbles (Eberle et al. 1980). Ages range from 20–15 Ma (Iturralde-Vinent and MacPhee 1996) and 20–23 million years (Baroni-Urbani and Saunders 1980) based on foraminifera counts and 45–30 Ma based on coccoliths (Cépek in Schlee 1990). These are considered minimum dates because they are based on microfossils in the strata containing the amber. Most of the amber is secondarily deposited in turbiditic sandstones of the Upper Eocene to Lower Miocene Mamey Group (Draper et al. 1994).

Mexican amber ptilodactyline beetle with attached pollinium of Annulites mexicana gen. n., sp. n. (arrow). Scale = 0.4 mm.

Mexican amber ptilodactyline beetle with attached pollinium of Annulites mexicana gen. n., sp. n. (arrow). Scale = 0.4 mm.@WFS News

The Mexican amber specimen originated from the Simojovel area of Chiapas, Mexico. Amber in this region occurs in lignitic beds among sequences of primarily marine calcareous sandstones and silt. The amber occurs in association with the Balumtun Sandstone formation of the early Miocene and the La Quinta formation of the Late Oligocene (Poinar 1992). These formations have been assigned radiometric ages from 22.5 to 26 million years (Berggren and Van Couvering 1974).

Pollinium (arrow) of Annulites mexicana gen. n., sp. n. attached to the mouthparts of a ptilodactyline beetle in Mexican amber. Scale = 0.3 mm.

Pollinium (arrow) of Annulites mexicana gen. n., sp. n. attached to the mouthparts of a ptilodactyline beetle in Mexican amber. Scale = 0.3 mm.

Observations and photographs were made with a Nikon SMZ-10 R stereoscopic microscope and Nikon Optiphot compound microscope with magnification up to 800×. Helicon Focus Pro X64 was used to stack photos for better clarity and depth of field.

Detail of annulated pollinia of Annulites mexicana gen. n., sp. n. Scale = 0.9 mm. Insert shows pollen tetrads (arrow) between segments. Scale = 80 μm.

Detail of annulated pollinia of Annulites mexicana gen. n., sp. n. Scale = 0.9 mm. Insert shows pollen tetrads (arrow) between segments. Scale = 80 μm.@WFS News

Citation: DOI: http://dx.doi.org/10.1093/ae/tmw055 172-177 First published online: 22 August 2016

Outlines of pollinaria of Cylindrocites browni gen. n., sp. n. (A) and Annulites mexicana gen. n., sp. n. (B). Arrows show viscidia.

Outlines of pollinaria of Cylindrocites browni gen. n., sp. n. (A) and Annulites mexicana gen. n., sp. n. (B). Arrows show viscidia.@WFS News

Key: @WFS News,WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: New T Rex fossil discovered

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

A significant new Tyrannosaurus rex fossil has been unearthed by palaeontologists from the Burke Museum of Natural History and Culture and the University of Washington (UW). The find includes a nearly complete skull.

Artwork of a Tyrannosaurus rex hunting

Computer artwork of a Tyrannosaurus rex dinosaur hunting an Ornithomimus dinosaur. T. rex was among the largest carnivorous dinosaurs. It was about 6 metres tall and weighed about 7 tonnes. T. rex lived in North America and Asia during the late Cretaceous period, between 85 and 65 million years ago. The head is heavily built and has the sharp teeth of a predator. T. rex is thought to have scavenged as well as hunted for food. The Ornithomimus dinosaur was about 6 metres long and 2 metres tall. It was an omnivore. It was fast and agile, thought to have been capable of speeds of up to 70 kilometres per hour. It lived from 76-65 million years ago. — Image by © Mark Garlick/Science Photo Library/Corbis

Despite the fact it is one of the most iconic and well-known dinosaurs, T Rex fossils are rare. The latest specimen is one of only 25 in the world at a similar level of completeness – the palaeontologists estimate they have uncovered about 20% of the animal. The skull, however, will be of most interest to researchers, given that there are currently only 15 reasonably complete T Rex skulls in the world. Palaeontologists will conduct further searches next summer, in an attempt to find more of the specimen.

The team, led by professor of biology at UW and curator of vertebrate palaeontology at Burke, Gregory P Wilson, discovered the fossil during an expedition to the Hell Creek Formation in northern Montana, USA – an area that’s renowned the world over for its dinosaur fossil sites. During one of the searches, a piece of fossilized bone protruding from a rocky hillside piqued the interest of two Burke volunteers, Jason Love and Luke Tufts. Upon further inspection, the team came across a skull, as well as ribs, vertebrae and parts of the jaw and pelvis.

T Rex was one of the largest and most fearsome dinosaurs to ever to roam the earth. On average, it measured 12 metres in length, and stood 4 and a half to 6 metres tall. Its size, combined with its sharp serrated teeth, made it a dangerous and effective predator. Evidence taken from the fossilised faeces of T Rex suggest it even ate fairly large dinosaurs like Edmontosaurus and Triceratops. It lived between about 66-68 million years ago in forested river valleys across western North America during the late Cretaceous Period – 145-66 million years ago.In honour of the two volunteers who spotted it, the specimen has been nicknamed the “Tufts-Love Rex”. Its skull measures about 1.2 metres long and weighs roughly 1100kg – although the team have covered it in a protective plaster casing in order to protect it during transport, meaning it will weigh more. Based on the size of its skull, the Burke palaeontologists estimate that the specimen is about 85% the size of the largest T Rex found to date and have suggested that it was about 15 years old when it died. T Rex usually lived up to about 25-30 years old.

Paleontologists prepare to remove a Tyrannosaurus rex skull from a fossil dig site in northern Montana and transport it to the Burke Museum at the University of Washington.Dave DeMar/Burke Museum/University of Washington

Paleontologists prepare to remove a Tyrannosaurus rex skull from a fossil dig site in northern Montana and transport it to the Burke Museum at the University of Washington.        Dave DeMar/Burke Museum/University of Washington

“We think the Tufts-Love Rex is going to be an iconic specimen for the Burke Museum and the state of Washington and will be a must-see for dinosaur researchers as well,” said Wilson.

The fossil is around 66.3 million years old, determined by the fact that it was found in a rock layer that marks the Cretaceous-Paleogene mass extinction event. The event, thought to have been caused by a massive comet or asteroid impact, occurred 66 million years ago wiping out three quarters of all life on earth.The expedition which found the fossils was part of the Hell Creek Project, a multidisciplinary, multi-institutional project designed to find out more about the mass extinction event, which killed of the dinosaurs, as well as the two million years or so which preceded, and succeeded it. It is currently led by Nathan Myhrvold and Jack Horner.

“This is really great news. The Hell Creek Project is responsible for finding the most T Rex specimens in the world, with 11 to date,” said Myhrvold, a leader of the project. “The T Rex has always been my favourite dinosaur and I’m really pleased that this one is going to make its home at the Burke Museum.”

“Having seen the ‘Tufts-Love Rex’ during its excavation I can attest to the fact that it is definitely one of the most significant specimens yet found, and because of its size, is sure to yield important information about the growth and possible eating habits of these magnificent animals,” said Horner.

Courtesy: article in ibtimes.co.uk

Key:WFS,World Fossil Society,Riffin T Sajeev,Russel T sajeev

WFS News:Soot may have killed off the dinosaurs and ammonites

A new hypothesis on the extinction of dinosaurs and ammonites at the end of the Cretaceous Period has been proposed by a research team from Tohoku University and the Japan Meteorological Agency’s Meteorological Research Institute.

The researchers believe that massive amounts of stratospheric soot ejected from rocks following the famous Chicxulub asteroid impact, caused global cooling, drought and limited cessation of photosynthesis in oceans. This, they say, could have been the process that led to the mass extinction of dinosaurs and ammonites.

Cadalene and long-chain n-alkanes are according to Mizukami et al.25. The map shows the paleolocations of the impact site and the sections evaluated. The base map is according to Courtillot et al.67

Cadalene and long-chain n-alkanes are according to Mizukami et al.. The map shows the paleolocations of the impact site and the sections evaluated. The base map is according to Courtillot et al.

The asteroid, also known as the Chicxulub impactor, hit Earth some 66 million years ago, causing a crater more than 180 km wide. It’s long been believed that that event triggered the mass extinction that led to the macroevolution of mammals and the appearance of humans.

Tohoku University Professor Kunio Kaiho and his team analyzed sedimentary organic molecules from two places — Haiti, which is near the impact site, and Spain, which is far. They found that the impact layer of both areas have the same composition of combusted organic molecules showing high energy. This, they believe, is the soot from the asteroid crash.

Soot is a strong, light-absorbing aerosol, and Kaiho’s team came by their hypothesis by calculating the amount of soot in the stratosphere estimating global climate changes caused by the stratospheric soot aerosols using a global climate model developed at the Meteorological Research Institute. The results are significant because they can explain the pattern of extinction and survival.

Global climate change caused by soot aerosol at the K-Pg boundary. Credit: Kunio Kaiho

Global climate change caused by soot aerosol at the K-Pg boundary. Credit: Kunio Kaiho

While it is widely accepted that the Chicxulub impact caused the mass extinction of dinosaurs and other life forms, researchers have been stumped by the process of how. In other words, they’d figured out the killer, but not the murder weapon.

Earlier theories had suggested that dust from the impact may have blocked the sun, or that sulphates may have contaminated the atmosphere. But researchers say it is unlikely that either phenomenon could have lasted long enough to have driven the extinction.

The new hypothesis raised by Kaiho’s team says that soot from hydrocarbons had caused a prolonged period of darkness which led to a drop in atmospheric temperature. The team found direct evidence of hydrocarbon soot in the impact layers and created models showing how this soot would have affected the climate.

According to their study, when the asteroid hit the oil-rich region of Chicxulub, a massive amount of soot was ejected which then spread globally. The soot aerosols caused colder climates at mid-high latitudes, and drought with milder cooling at low latitudes on land. This in turn led to the cessation of photosynthesis in oceans in the first two years, followed by surface-water cooling in oceans in subsequent years.

This rapid climate change is believed to be behind the loss of land and marine creatures over several years, suggesting that rapid global climate change can and did play a major role in driving extinction.

Kaiho’s team is studying other mass extinctions in the hopes of further understanding the processes behind them.

Citation:Tohoku University. “Soot may have killed off the dinosaurs and ammonites.” ScienceDaily. ScienceDaily, 15 July 2016. <www.sciencedaily.com/releases/2016/07/160715113558.htm, doi:10.1038/srep28427

Key: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Mioneophron longirostris, Fossil vulture found from the Late Miocene of China

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

Neogene fossils of Old World vultures (Aegypiinae and Gypaetinae) are known from Africa, Eurasia, and North America. The evolution of Old World Vultures is closely tied to the expansion of grasslands and open woodlands and appearance of large, grazing mammals.  While there are no extant Old World vultures in the Americas today, a large diversity of Gypaetinae are known from Miocene to late Pleistocene fossil deposits. Despite a comparatively large number of North American Gypaetinae fossils, complete specimens have rarely been reported from Eurasia and Africa.

 Reconstruction of Mioneophron longirostris. Credit: XU Yong

Reconstruction of Mioneophron longirostris. Credit: XU Yong

In a recent study published online on July 20 in the journal Auk, LI Zhiheng and Clarke Julia from the University of Texas at Austin and their collaborators ZHOU Zhonghe and DENG Tao from IVPP described the exceptional skeleton of a new Gypaetinae vulture, Mioneophron longirostris, from the late Miocene deposits of the Linxia Basin in northwestern China. In comparison with other extant and extinct Old World vultures, the new specimen has a slender and elongated rostrum, similar to the beaks of the Egyptian Vulture (Neophron percnopterus; Gypaetinae) and the Hooded Vulture (Necrosyrtes monachus; Aegypiinae). Based on the comprehensive examination of Old World vulture records and their skeletal features, the new specimen was identified as the oldest record of Gypaetinae from Eurasia or Africa.

A re-examination of the geographic and temporal distribution of Old World vultures from Neogene deposits indicates that the Gypaetinae diversified during the expansion of grasslands in the early-mid Miocene. The diversification of Aegypiinae is linked to the later transition from C3 to C4 grasslands during the late Miocene and early Pliocene. The ranges of Old World vultures retracted from North America, Southeast Asian islands, and east China with the extinction of mammalian megafauna at the end of the Pleistocene.

Photograph and line drawing of Mioneophron longirostris. Credit: LI Zhiheng

Photograph and line drawing of Mioneophron longirostris. Credit: LI Zhiheng

To date, only a handful of bird fossils have been reported from late Miocene deposits in the Linxia Basin, including a large–bodied and flightless ostrich (Struthio linxiaensis), an Aegypiinae vulture (Gansugyps linxiaensis) and an early kestrel (Falco hezhengensis). Mioneophron represents the fourth bird species from the region and reveals a savanna-like environment in northwest China during the late Miocene.

Courtesy: phys.org/news

Citation: Zhiheng Li et al. A new Old World vulture from the late Miocene of China sheds light on Neogene shifts in the past diversity and distribution of the Gypaetinae, The Auk (2016). DOI: 10.1642/AUK-15-240.1

WFS News: Finding Britain’s last hunter-gatherers utilising bone collagen

@ WFS ,World Fossil Society,Riffin T Sajeev,Russel T sajeev
Finding Britain’s last hunter-gatherers: A new biomolecular approach to ‘unidentifiable’ bone fragments utilising bone collagen

doi:10.1016/j.jas.2016.07.014

In the last decade, our knowledge of the transition from foraging, fishing, and hunting to agricultural food production has been transformed through the molecular analysis of human remains. In Britain, however, the lack of Late Mesolithic human remains has limited our understanding of this dietary transition. Here, we report the use of a novel strategy to analyse otherwise overlooked material to identify additional human remains from this period. ZooMS, a method which uses bone collagen sequences to determine species, was applied to unidentifiable bone fragments from 5th millennium deposits from the Late Mesolithic site of Cnoc Coig (Oronsay, Inner Hebrides) using an innovative new methodology. All samples bar one produced ZooMS results, with 14/20 bone fragments identified as human, and the remainder a mixture of pig and seal. 70% of bone fragments had sufficient collagen for stable isotope analyses, however none of three human bone fragments analysed had sufficient endogenous DNA. By conducting AMS dating and stable isotope analysis on this identified collagen, we provide new data that supports the view that the exploitation of marine resources partially overlapped with the earliest agricultural communities in Britain, and thus argues against the idea that forager lifeways in Britain were immediately replaced by agriculture c.4000 cal. BC. Unfortunately, we were unable to explore the genetic relationship between contemporaneous farmers and foragers. However, the more persistent bone protein could be used to identify species, determine date, and assess diet. This novel approach is widely applicable to other early prehistoric sites with fragmentary skeletal material.
Selection of bone fragments from the Cnoc Coig assemblage used within this research; highlighting the range of sizes, elements and preservation. From top, L-R, ZooMS IDs: seal, pig, remainder human.

Selection of bone fragments from the Cnoc Coig assemblage used within this research; highlighting the range of sizes, elements and preservation. From top, L-R, ZooMS IDs: seal, pig, remainder human.                                                                                                             

WFS News: New light shed on how vertebrates see

The success of vertebrates is linked to the evolution of a camera-style eye and sophisticated visual system. In the absence of useful data from fossils, scenarios for evolutionary assembly of the vertebrate eye have been based necessarily on evidence from development, molecular genetics and comparative anatomy in living vertebrates. Unfortunately, steps in the transition from a light-sensitive ‘eye spot’ in invertebrate chordates to an image-forming camera-style eye in jawed vertebrates are constrained only by hagfish and lampreys (cyclostomes), which are interpreted to reflect either an intermediate or degenerate condition. Here, we report—based on evidence of size, shape, preservation mode and localized occurrence—the presence of melanosomes (pigment-bearing organelles) in fossil cyclostome eyes. Time of flight secondary ion mass spectrometry analyses reveal secondary ions with a relative intensity characteristic of melanin as revealed through principal components analyses. Our data support the hypotheses that extant hagfish eyes are degenerate, not rudimentary, that cyclostomes are monophyletic, and that the ancestral vertebrate had a functional visual system. We also demonstrate integument pigmentation in fossil lampreys, opening up the exciting possibility of investigating colour patterning in Palaeozoic vertebrates. The examples we report add to the record of melanosome preservation in Carboniferous fossils and attest to surprising durability of melanosomes and biomolecular melanin.

Fossil cyclostomes from the Mazon Creek Lagerstätte. (a) Myxinikela siroka (PF15373). Scale bar, 5 mm. (b) Mayomyzon pieckoensis (ROMV56800b) showing clearly defined pigmented stripes along the dorsal surface. Scale bar, 5 mm. (c–e) Back-scattered electron (BSE) SEM images of melanosomes present in the eyes of (c) Myxinikela siroka (PF15373), (d) Mayomyzon pieckoensis (LEIUG 123268) and (e) Mayomyzon pieckoensis (ROM56806); note two distinct melanosome morphologies, which is typical of the RPE of fish [12–14]. All scale bars, 5 µm. Not all material preserved as carbon within the fossils shows these textures; for example, in Mayomyzon the oral disc and pharynx comprise sheet-like carbon with associated pyrite. Ellipsoid/oblate textures are not evident in carbon patches beyond the margins of the body in any of the taxa studied. (f) Radial TEM image of the retina of an extant fish (Rhinogobius). Dark pigment granules (melanosomes) are elliptical in the base of the image and spherical at the top of the image. Decay-induced collapse of the RPE would result in a fossilized structure with both elliptical and oblate melanosome morphologies. Scale bar, 5 µm. Image courtesy of Gengo Tanaka. e, eye; ot, oral tentacles; snc, forked subnasal cartilage; b, branchial structure; d, digestive organ; oc, otic capsule, od, oral disc; as, axial structure. (Online version in colour.)

Fossil cyclostomes from the Mazon Creek Lagerstätte. (a) Myxinikela siroka (PF15373). Scale bar, 5 mm. (b) Mayomyzon pieckoensis (ROMV56800b) showing clearly defined pigmented stripes along the dorsal surface. Scale bar, 5 mm. (c–e) Back-scattered electron (BSE) SEM images of melanosomes present in the eyes of (c) Myxinikela siroka (PF15373), (d) Mayomyzon pieckoensis (LEIUG 123268) and (e) Mayomyzon pieckoensis (ROM56806); note two distinct melanosome morphologies, which is typical of the RPE of fish [12–14]. All scale bars, 5 µm. Not all material preserved as carbon within the fossils shows these textures; for example, in Mayomyzon the oral disc and pharynx comprise sheet-like carbon with associated pyrite. Ellipsoid/oblate textures are not evident in carbon patches beyond the margins of the body in any of the taxa studied. (f) Radial TEM image of the retina of an extant fish (Rhinogobius). Dark pigment granules (melanosomes) are elliptical in the base of the image and spherical at the top of the image. Decay-induced collapse of the RPE would result in a fossilized structure with both elliptical and oblate melanosome morphologies. Scale bar, 5 µm. Image courtesy of Gengo Tanaka. e, eye; ot, oral tentacles; snc, forked subnasal cartilage; b, branchial structure; d, digestive organ; oc, otic capsule, od, oral disc; as, axial structure. (Online version in colour.)

Citation:

  1. Sarah E. Gabbott, Philip C. J. Donoghue, Robert S. Sansom, Jakob Vinther, Andrei Dolocan, Mark A. Purnell. Pigmented anatomy in Carboniferous cyclostomes and the evolution of the vertebrate eye.Proceedings of the Royal Society B: Biological Sciences, 2016; 283 (1836): 20161151 DOI: 10.1098/rspb.2016.1151

Key: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

An analysis on predatory signatures on Miocene oysters Of Crassostrea Sp.from east coast of southern India

Riffin T Sajeev*

Department of Geology, Periyar University, Salem,INDIA .*riffin@rediffmail.com

The eastern coast lines of southern India are rarely used to study its paleontological importance. Living oysters of Crassostrea Sp. are found throughout these coastal margins. Recent reports indicate the existence of a paleo-estuary dated to the mio-pliocene age, along the valleys of the southern end of Western Ghats. About 70 specimen of Crassostrea Sp. have been sampled from this area of which, almost 80 percent are disarticulated and observed as subjected to the predatory action of ichnotaxa.

Crassostrea Fossil with action of ichnotaxa.(c) World Fossil Society. Photo Courtesy @Riffin T Sajeev & Russel T Sajeev

Crassostrea Fossil with action of ichnotaxa.          (c) World Fossil Society. Photo Courtesy            @Riffin T Sajeev & Russel T Sajeev

All oysters seem to have adapted extremely thick layered calcite shells, which is a remarkable morphological feature. Bore holes and biodegradation are seen in an extreme magnitude. A previous work of the author describes the existence of a giant Paleo-estuary which existed along the eastern coastlines of India during the mio-pliocene age, based on the morphological and taxonomical features of Crassostrea Sp. from the same area. The proposed work is a detailed analysis of the Predatory signatures on shell fragments by ichospecies in the proposed paleo-estuary during the mio-pliocene age.

Crassostrea Fossil with action of ichnotaxa.(c) World Fossil Society. Photo Courtesy @Riffin T Sajeev & Russel T Sajeev

Crassostrea Fossil with action of ichnotaxa.          (c) World Fossil Society. Photo Courtesy @                         Riffin T Sajeev & Russel T Sajeev

In this study, the author analyzes the nature of the ichnospecies that thrived among these oysters, their threat to the life of oysters and their contribution towards the necessity for an adaptation of a thick layered shell on these oysters. The study proposes to identify each ichnotaxa by analyzing their predatory pattern and the style of biodegradation on the host shells. The study also proposes to explain the paleo-climate and paleo-topography and further insight to the nature of sediments in the estuary during the mio-pliocene, based on the features on the samples of Crassostrea Sp.

Citation: Geological Society Of America Annual meeting At Denver,2016

Key: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

WFS News: Earth’s mantle appears to have a driving role in plate tectonics

Deep down below us is a tug of war moving at less than the speed of growing fingernails. Keeping your balance is not a concern, but how the movement happens has been debated among geologists.

New findings from under the Pacific Northwest Coast by University of Oregon and University of Washington scientists now suggest a solution to a mystery that surfaced when the theory of plate tectonics arose: Do the plates move the mantle, or does the mantle move the plates.

The separation of tectonic plates, the researchers proposed in a paper online ahead of print in the journal Nature Geoscience, is not simply dictating the flow of the gooey, lubricating molten material of the mantle. The mantle, they argue, is actually fighting back, flowing in a manner that drives a reorientation of the direction of the plates.

The new idea is based on seismic imaging of the Endeavor segment of the Juan de Fuca Plate in the Pacific Ocean off Washington and on data from previous research on similar ridges in the mid-Pacific and mid-Atlantic oceans.

Brandon VanderBeek, a doctoral student at the University of Oregon, led a study that investigated interactions of the Earth's mantle and tectonic plates off the coast of Washington state. Credit: University of Oregon

Brandon VanderBeek, a doctoral student at the University of Oregon, led a study that investigated interactions of the Earth’s mantle and tectonic plates off the coast of Washington state.Credit: University of Oregon

“Comparing seismic measurements of the present mantle flow direction to the recent movements of tectonic plates, we find that the mantle is flowing in a direction that is ahead of recent changes in plate motion,” said UO doctoral student Brandon P. VanderBeek, the paper’s lead author. “This contradicts the traditional view that plates move the mantle.”

While the new conclusion is based on a fraction of such sites under the world’s oceans, a consistent pattern was present, VanderBeek said. At the three sites, the mantle’s flow is rotated clockwise or counterclockwise rather than in the directions of the separating plates. The mantle’s flow, the researchers concluded, may be responsible for past and possibly current changes in plate motion.

The research — funded through National Science Foundation grants to the two institutions — also explored how the supply of magma varies under mid-ocean ridge volcanoes. The researchers conducted a seismic experiment to see how seismic waves moved through the shallow mantle below the Endeavor segment.

They found that the middle of the volcanic segment, where the seafloor is shallowest and the inferred volcanic activity greatest, the underlying mantle magma reservoir is relatively small. The ends, however, are much deeper with larger volumes of mantle magma pooling below them because there are no easy routes for it to travel through the material above it.

Traditional thinking had said there would be less magma under the deep ends of such segments, known as discontinuities.

“We found the opposite,” VanderBeek said. “The biggest volumes of magma that we believe we have found are located beneath the deepest portions of the ridges, at the segment ends. Under the shallow centers, there is much less melt, about half as much, at this particular ridge that we investigated.

“Our idea is that the ultimate control on where you have magma beneath these mountain ranges is where you can and cannot take it out,” he said. “At the ends, we think, the plate rips apart much more diffusely, so you are not creating pathways for magma to move, build mountains and allow for an eruption.”

WFS,World Fossil Societry,Riffin T Sajeev,Russel T Sajeev

WFS News : Heterodontosaurus tucki Fossil found in SA finally gives up its secrets

Johannesburg – A remarkable dinosaur fossil discovery made by a South African palaeontologist in 2005 has finally revealed its secrets.The fossil, the most complete ever found of a species known as Heterodontosaurus tucki, was recently scanned at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France.

Fossil skull of Heterodontosaurus tucki

Fossil skull of Heterodontosaurus tucki

The Evolutionary Studies Institute at the University of the Witwatersrand (Wits) in Johannesburg took the complete skeleton of the small dinosaur to the ESRF. The dinosaur is believed to have roamed the earth 200 million years ago.Billy de Klerk found the fossil in a stream bed on a farm near Grahamstown in the Eastern Cape.

The dinosaur was scanned between July 21 and July 26.

“Heterodontosaurus was a small, plant-eating animal with grinding teeth in the back of the jaw and big canines in the front,” the ESRF’s spokesperson Delphine Chenevier said in a statement.

De Klerk excavated the fossil from the stream bed and removed enough rock from the bones to identify the animal. The skeleton was, however, too small and delicate, and the rocks around it too hard to enable scientists to fully study the anatomy. The fossil was therefore sent to the ESRF, where it was X-rayed.

Artistic impression about Fossil skull of Heterodontosaurus tucki

Artistic impression about Fossil skull of Heterodontosaurus tucki

“That’s where the synchrotron comes in: the high-energy X-rays generated… will allow scientists to reconstruct the skeleton in incredible detail,” said Chenevier.

A team of scientists, led by Wits Prof Jonah Choiniere, with the ESRF’s palaeontologist Dr Vincent Fernandez, scanned the specimen with high-powered X-rays. They wanted to understand how Heterodontosaurus ate, moved, and breathed.

“We think the back teeth are used for grinding,” Chenevier said.

“Typically, in dinosaurs that have grinding dentition, they have a certain type of tooth replacement, that is: teeth grow inside the jaw and gradually replace those grinding teeth as they wear down. Lots of scientists have speculated about tooth replacement in Heterodontosaurus. Now this is the first time that we have a complete jaw and we can actually test some of those speculations.”

Choiniere said the scans revealed details of the bones forming the roof of the mouth.

“We can see the palate and the mid-line of the skull and those palate bones are really very fine, less than 1mm across. We’ve scanned this at such a good resolution that we can actually see the outlines of the palate bones very, very well.”

Source:news24.com

Key: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev