Bone Eating Worms Originally Evolved to eat Marine Reptiles, not Whales

A species of bone-eating worm that was believed to have evolved in conjunction with whales has been dated back to prehistoric times when it fed on the carcasses of giant marine reptiles.

Scientists at Plymouth University found that Osedax - popularised as the 'zombie worm' - originated at least 100 million years ago, and subsisted on the bones of prehistoric reptiles such as plesiosaurs and sea turtles.

Reporting in the Royal Society journal Biology Letters this month, the research team at Plymouth reveal how they found tell-tale traces of Osedax on plesiosaur fossils held in the Sedgwick Museum at the University of Cambridge.

Dr Nicholas Higgs, a Research Fellow in the Marine Institute, said the discovery was important for both understanding the genesis of the species and its implications for fossil records. "The exploration of the deep sea in the past decades has led to the discovery of hundreds of new species with unique adaptations to survive in extreme environments, giving rise to important questions on their origin and evolution through geological time." said Nicholas. "The unusual adaptations and striking beauty of Osedax worms encapsulate the alien nature of deep-sea life in public imagination.

"And our discovery shows that these bone-eating worms did not co-evolve with whales, but that they also devoured the skeletons of large marine reptiles that dominated oceans in the age of the dinosaurs. Osedax, therefore, prevented many skeletons from becoming fossilised, which might hamper our knowledge of these extinct leviathans."

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A New Exceptionally Preserved Cambrian Priapulid Worm

A New Exceptionally Preserved Cambrian Priapulid From The Chengjiang Lagerstätte

Authors:

Ma et al

Abstract:

A fossil priapulid, Eximipriapulus globocaudatus new genus new species, is described from the Cambrian Chengjiang Lagerstätte of Yunnan, China. The exceptional preservation of the animal reveals morphological details that allow direct comparison with extant priapulids. The body is divisible into a partially eversible pharynx, a smooth collar, a scalid-bearing introvert, a neck with triangular scalids, an unsegmented trunk with annulations, and a distinctly expanded terminal region. Several specialized regions of the alimentary canal are recognized: a pharynx (lined by cuticle and bearing teeth), esophagus, midgut, hindgut, and a terminal anus. The sample includes a putative juvenile. The animal is inferred to have been an active burrower using a double-anchor strategy, practicing both deposit feeding and carnivory. Inclusion of Eximipriapulus in the most recent character matrix for cladistic analysis of fossil and Recent priapulids resolves the new genus within the priapulid crown group.

Tetrapod & Invertebrate Trace Fossils From Early Permian Argentina

Tetrapod and invertebrate trace fossils from aeolian deposits of the lower Permian of central-western Argentina

Authors:

Krapovickas et al

Abstract:

Abundant tetrapod footprints are described from the Early Permian Yacimiento Los Reyunos Formation including both collected and in situ specimens. The slabs come from several quarries at the Sierra Pintada and Sierra de las Peñas area, south-west of Mendoza, Argentina. The trace fossil assemblage, which constitutes one of the oldest known from Gondwana, comprises excellent-preserved tetrapod tracks (Chelichnusduncani, Chelichnusgigas and ‘pear-like’ footprints) and invertebrate simple sub-horizontal (Palaeophycustubularis) and vertical (Skolithos isp.) burrows formed in a aeolian dune field. The analysis of the tetrapod track producers indicates the presence of at least three different taxa of sprawling to semi-erect therapsids, thus suggesting the presence of members of this clade, or closest relatives, in the Early Permian of southern Gondwana. Moreover, a series of measurements and simple indexes were developed to estimate body proportions and locomotion styles of the putative trackmakers. The new assemblage, analysed in the context of other known Permian assemblages from Pangea, is one the few known in Gondwana to be present in an aeolian environment. The evaluation of the assemblage, in the light of aeolian ichnofacies (Chelichnus, Octopodichnus and Entradichnus), shows that it has common elements with the Chelichnus and Entradichnus ichnofacies.

Attack of the Killer Sponges

hat tip to the Running Ponies.

Not All Organisms Respond to Mass Extinctions in the Same Way: no Lilliput Effect on K-Pg Extinction Bryozoans

The sizes of organisms following mass extinction events may vary more than previously thought, which may be inconsistent with the predictions of the so-called 'Lilliput effect,' according to a study published in PLOS ONE on February 5, 2014 by Caroline Sogot from University of Cambridge and colleagues.

Scientists associate mass extinction events like the Cretaceous-Paleogene (abbreviated K-Pg) event with a reduction in organism size in the aftermath, a phenomenon termed 'the Lilliput effect.' These pronounced changes are thought to be in response to lower food availability and other alterations in the environment that can occur following a mass extinction event. Therefore, survivors of the K-Pg mass extinction should exhibit smaller body size than their pre-extinction relatives. To delve more into this effect, scientists investigated the changes in size of an aquatic invertebrate at the individual- and colony-level before and after the mass extinction.

Scientists analyzed of the 59 bryozoan species and found no significant change in body length. Additionally, the sizes of two types of bryozoan colonies, 210 Maastrichtian colonies and 163 Danian colonies, did not show consistent size decrease before and after the K-Pg extinction event, although maximum colony size did decline in three out of four surviving types of bryozoan. The authors suggest that the lack of size change in the majority of bryozoans studied here may indicate that the Lilliput effect is not universal at all levels, and that the response may vary across organisms.

Dr. Sogot added, "The absence of a clear 'Lilliput effect' in the bryozoans analysed in this study suggests that not all organisms respond in the same manner to all mass extinction events."

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Ectobius Genus Cockroaches Were Native to North America...during the Eocene Paleogene!

The cockroach in the genus Ectobius is a major textbook example of an invasive organism, and it is the most common cockroach inhabiting a large region from northernmost Europe to southernmost Africa.

Ectobius has a long fossil history in Europe, occurring in Baltic amber that is about 44 million years old, and its lineage was believed to have been exclusively from the Old World. However, a shocking new discovery has uprooted that view. In fact, it now appears that Ectobius may have originated in the New World.

Four ancient Ectobius species were recently discovered in the 49-million-year-old Green River Formation near Rifle, Colorado in deposits that are about five million years older than the Baltic amber. However, these cockroaches soon became extinct in North America. The cause for the extinction of Ectobius in North America in the dim past is unknown, but it evidently survived in the Old World, and western Europe in particular.

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A Cryptic Coral-crinoid "Hanging Garden" From Eifelian/Givetian Devonian Morocco

Cryptic coral-crinoid "hanging gardens" from the Middle Devonian of southern Morocco

Authors:

Jakubowicz et al

Abstract:

An unusual and exceptionally well preserved cryptic community of cnidarians, crinoids, sponges, and microbes developed in a submarine cavity of Middle Devonian age in the Hamar Laghdad area (Morocco). The biota encrusted the cavity roof and grew predominantly in an upside-down position, forming spectacular "hanging gardens." The investigated assemblage differs strikingly from both its Paleozoic and modern analogues; it constitutes one of a very few known examples of fossil cryptic assemblages developed in relatively deep water settings, and is the first report of a cryptic paleoecosystem dominated by rugose corals. The results support the view that during the middle Paleozoic there was no distinct polarization between open-surface and cryptic faunas in deep-water environments, but keen competition for space already existed in Devonian cryptic assemblages. The regional species pool seems to have been the main determinant of the ecological succession and structure of this cryptic community.

Toarcian Jurassic Oceanic Anoxic Event Evidence From Foraminifera and Ostracods Isotopic Evidence

Stable isotopes on foraminifera and ostracods for interpreting incidence of the Toarcian Oceanic Anoxic Event in Westernmost Tethys: Role of water stagnation and productivity

Author:

Matías Reolid

Abstract:

The analysis of δ13C and δ18O from whole rock and the shells of selected foraminifera (Lenticulina and Dentalina) and bairdioid ostracods from Lower Toarcian of the South Iberian Palaeomargin (Western Tethys) is presented with the aim of improving knowledge of the processes and the environmental effects of the Toarcian Oceanic Anoxic Event. In addition, isotopic data are compared with geochemical redox and palaeoproductivity proxies. The microhabitat affected δ13C values, δ13CLenticulina generally being lower than δ13CDentalina due to more depleted 13C values for sediment pore-water in the deep infaunal microhabitat. The lowest values of δ13C (lower part of Serpentinum Zone) happen during suboxic conditions, as indicated by redox proxies, low diversity and abundance of foraminifera and higher TOC values. The fine-grained, organic rich sediments allow for conditions favouring pore-water dissolved inorganic carbon that is depleted in 13C with respect to that of the bottom sea-water, particularly during the suboxic conditions. The δ13C of potential deep infauna (Lenticulina) reflects the oxygen restricted conditions better than shallow infauna (Dentalina) and whole sediment. Regarding δ18O, values from bulk rock present stronger fluctuations and lower values than δ18ODentalina and δ18OLenticulina. The stratigraphic differences between δ18ODentalina and δ18OLenticulina correspond to vital effects, since no important fluctuations in temperature occurred in the bottom sea-water, as deduced from the absence of peaks and stratigraphic trends in the interval studied. The δ18O values do not allow us to infer temperature changes related to the Toarcian Oceanic Anoxic Event in this part of the palaeomargin.

Trilobites Invaded Tidal Flats During the Early Cambrian

Trilobites in early Cambrian tidal flats and the landward expansion of the Cambrian explosion

Authors:

Mángano et al

Abstract:

The timing of the early invasion of the continents, the routes to the land, and the environmental breadth of the Cambrian explosion are important topics because they are at the core of our understanding of early evolutionary breakthroughs. Illuminating some aspects of these problems are trilobite trace fossils in tidal-flat deposits from the lower Cambrian Rome Formation in the southern Appalachian Mountains of Tennessee (USA). Morphologic details and size range of the trace fossils suggest production by olenellid trilobites, which occur as body fossils in the same unit. The occurrence of this ichnofauna, together with physical structures indicative of periodic subaerial exposure (desiccation cracks) and deposition within the intertidal zone (flat-topped ripples), shows that trilobites forayed into the upper intertidal zone during the Cambrian. Our finding supports the migration of subtidal organisms into marginal-marine, intertidal settings at the dawn of the Phanerozoic, suggesting that trilobites contributed to the establishment of the intertidal ecosystem during the Cambrian. The sequence of events involved in the colonization of early Paleozoic tidal flats is consistent with the idea that most terrestrial taxa originated from marine rather than freshwater ancestors, and that direct routes to the land from marginal-marine ecosystems were involved in the colonization of continental environments early in the Phanerozoic.

Permian Relatives of Ants, Wasps and Bees Found in Russia

Wasps, bees, ants and relatives comprise the megadiverse insect order Hymenoptera, the third most speciose animal group on Earth, far surpassing the number of known vertebrate species. All the four most diverse orders of animals (beetles, butterflies, wasps, and true flies) belong to the group of insects with complete metamorphosis, i.e. having a dormant pupa, jointly known as Holometabola. Other holometabolans are lacewings, alderflies, dobsonflies, snakeflies, scorpionflies, fleas, and caddisflies. Hymenopterans are currently regarded as a very old lineage, which had been the first to separate from the holometabolan stem, the view supported by molecular evidence.

Eighty years ago the Russian entomologist Andrey Martynov—well known for naming the two major divisions of winged insects Palaeoptera and Neoptera, stressing the importance of the wing folding pattern for insect evolution—suggested that wasps had arisen from snakefly-like ancestors.

New fossils, which are 260–270 million years old, support his view, firmly attaching the wasp lineage to the lacewing (neuropteroid) branch of the holometabolan family tree and dating its origin no earlier than Late Permian. These fossils are the oldest known Megaloptera: alderfly-like Parasialidae, and a newly discovered closely related family Nanosialidae.

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HC Wang was Right: Scleractinian Corals are Derived Rugosa Corals

The Rugosa-Scleractinia gap re-examined through microstructural and biochemical evidence: a tribute to H.C. Wang

Author:

Jean-Pierre Cuif

Abstract:

More than sixty years ago, H.C. Wang carried out an extensive study of skeletal microstructures of the Paleozoic corals and concluded that a “direct descent” may have existed between the two coral suborders: the Paleozoic Rugosa and the younger Scleractinia that had been established as distinct phyla by Haeckel (1896). Skeletal microstructures and three-dimensional reconstructions of walls and septa have revealed remarkable similarities between some Permian and Triassic corals, but it is only during the recent years that significant relationships were established between the structural properties of coral skeletons and their control by the biological process. Supported by recent genetic studies of calcareous biomineralization among various invertebrate phyla, the Wang's opinion now appears a reasonable working hypothesis.

Earliest Known Metamorphising Insects are From the Gzhelian Pennsylvanian Carboniferous

The earliest known holometabolous insects

Authors:

Nel et al.

Abstract:

The Eumetabola (Endopterygota (also known as Holometabola) plus Paraneoptera)1 have the highest number of species of any clade, and greatly contribute to animal species biodiversity. The palaeoecological circumstances that favoured their emergence and success remain an intriguing question. Recent molecular phylogenetic analyses have suggested a wide range of dates for the initial appearance of the Holometabola, from the Middle Devonian epoch (391 million years (Myr) ago) to the Late Pennsylvanian epoch (311 Myr ago), and Hemiptera (310 Myr ago). Palaeoenvironments greatly changed over these periods, with global cooling and increasing complexity of green forests. The Pennsylvanian-period crown-eumetabolan fossil record remains notably incomplete, particularly as several fossils have been erroneously considered to be stem Holometabola; the earliest definitive beetles are from the start of the Permian period. The emergence of the hymenopterids, sister group to other Holometabola, is dated between 350 and 309 Myr ago, incongruent with their current earliest record (Middle Triassic epoch). Here we describe five fossils— a Gzhelian-age stem coleopterid, a holometabolous larva of uncertain ordinal affinity, a stem hymenopterid, and early Hemiptera and Psocodea, all from the Moscovian age—and reveal a notable penecontemporaneous breadth of early eumetabolan insects. These discoveries are more congruent with current hypotheses of clade divergence. Eumetabola experienced episodes of diversification during the Bashkirian–Moscovian and the Kasimovian–Gzhelian ages. This cladogenetic activity is perhaps related to notable episodes of drying resulting from glaciations, leading to the eventual demise in Euramerica of coal-swamp ecosystems, evidenced by floral turnover during this interval. These ancient species were of very small size, living in the shadow of Palaeozoic-era ‘giant’ insects. Although these discoveries reveal unexpected Pennsylvanian eumetabolan diversity, the lineage radiated more successfully only after the mass extinctions at the end of the Permian period, giving rise to the familiar crown groups of their respective clades.

Excellent Mating Insects Fossils From Callovian Jurassic China

Forever Love: The Hitherto Earliest Record of Copulating Insects from the Middle Jurassic of China

Authors:

Shu Li, Chungkun Shih, Chen Wang, Hong Pang and Dong Ren

Abstract:

Background

Mating behaviors have been widely studied for extant insects. However, cases of mating individuals are particularly rare in the fossil record of insects, and most of them involved preservation in amber while only in rare cases found in compression fossils. This considerably limits our knowledge of mating position and genitalia orientation during the Mesozoic, and hinders our understanding of the evolution of mating behaviors in this major component of modern ecosystems.

Principal Finding

Here we report a pair of copulating froghoppers, Anthoscytina perpetua sp. nov., referable to the Procercopidae, from the Middle Jurassic of northeastern China. They exhibit belly-to-belly mating position as preserved, with male's aedeagus inserting into the female's bursa copulatrix. Abdominal segments 8 to 9 of male are disarticulated suggesting these segments were twisted and flexed during mating. Due to potential taphonomic effect, we cannot rule out that they might have taken side-by-side position, as in extant froghoppers. Genitalia of male and female, based on paratypes, show symmetric structures.

Conclusions/Significance

Our findings, consistent with those of extant froghoppers, indicate froghoppers' genitalic symmetry and mating position have remained static for over 165 million years.

Arthropods in Patagonia Were Less Impacted by KT/K-Pg Extinction

There may be some truth to the old joke about only insects surviving an apocalypse.

Down in Patagonia, thousands of miles from the site of the deadly asteroid impact in present-day Mexico that killed off the dinosaurs, most bugs easily survived one of Earth's worst mass extinctions 65 million years ago. The discovery adds to a growing body of evidence that the Cretaceous mass extinction had varied effects on species in different spots around the world.

Evidence from fossilized leaves suggests that, compared with insects in North America, a greater diversity of insects in South America chewed, sucked and otherwise fed off plants after the Cretaceous extinction, researchers reported Oct. 28 at the Geological Society of America's annual meeting in Denver.

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Earliest Known Complete Nervous System Found in Cambrian Megacheiran Fossil

Research led by University of Arizona Regents' Professor Nick Strausfeld and London Natural History Museum's Greg Edgecombe has revealed that the ancestors of chelicerates (spiders, scorpions and their kin) branched off from the family tree of other arthropods – including insects, crustaceans and millipedes – more than half a billion years ago.

The team discovered the earliest known complete nervous system exquisitely preserved in the fossilized remains of a never-before described creature that crawled or swam in the ocean 520 million years ago.

Described in the current issue of the journal Nature, the find belongs to an extinct group of marine arthropods known as megacheirans (Greek for "large claws") and solves the long-standing mystery of where this group fits in the tree of life.

"We now know that the megacheirans had central nervous systems very similar to today's horseshoe crabs and scorpions," said the senior author of the study, Nicholas Strausfeld, a Regents' Professor in the University of Arizona's department of neuroscience. "This means the ancestors of spiders and their kin lived side by side with the ancestors of crustaceans in the Lower Cambrian."

The scientists identified the 3-centimeter-long creature (a little over an inch) unearthed from the famous Chengjiang formation near Kunming in southwest China, as a representative of the extinct genus Alalcomenaeus. Animals in this group had an elongated, segmented body equipped with about a dozen pairs of body appendages enabling the animal to swim or crawl or both. All featured a pair of long, scissor-like appendages attached to the head, most likely for grasping or sensory purposes, which gave them their collective name, megacheirans.

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Crustaceans Suffered as Much as Coral Reefs Between the Permian Extinction to the Tithonian Jurassic

Many ancient crustaceans went extinct following a massive collapse of reefs across the planet, and new University of Florida research suggests modern species living in rapidly declining reef habitats may now be at risk.

Available online and scheduled to appear in the November issue of Geology, the study shows a direct correlation between the amount of prehistoric reefs and the number of decapod crustaceans, a group that includes shrimp, crab and lobster. The decline of modern reefs due to natural and human-influenced changes also could be detrimental, causing a probable decrease in the biodiversity of crustaceans, which serve as a vital food source for humans and marine animals such as fish, said lead author Adiël Klompmaker, a postdoctoral researcher at the Florida Museum of Natural History on the UF campus who started the study at Kent State University.

“We estimate that earth’s decapod crustacean species biodiversity plummeted by more than 50 percent during a sharp decline of reefs nearly 150 million years ago, which was marked by the extinction of 80 percent of crabs,” Klompmaker said. “If reefs continue to decline at the current rate during this century, then a few thousand species of decapods are in real danger. They may adapt to a new environment without reefs, migrate to entirely new environments or, more likely, go extinct.”

Some scientists predict as much as 20 percent of the world’s reefs may collapse within 40 years, with a much higher percentage affected by the end of the century due to natural and human-influenced changes such as ocean acidification, diseases and coral bleaching.

The study is the first comprehensive examination of the rise of decapod crustaceans in the fossil record. Researchers created a database of fossils from the Mesozoic Era, 252 million to 66 million years ago, from literature records based on museum specimens worldwide. The data included 110 families, 378 genera and 1,298 species. They examined the patterns of diversity and found an increase in the number of decapod species was influenced by the abundance of reefs, largely due to the role of reefs as a provider of shelter and foraging. Researchers call this period the “Mesozoic decapod revolution” because of the 300-fold increase in species diversity compared with the previous period and the appearance and rapid evolution of crabs.

Compiling information about crustaceans on this scale has historically been a challenge for researchers because most decapods possess a fragile and weakly calcified exoskeleton that does not fossilize well.

“Only a scant fraction of decapod crustaceans is preserved in rocks, so their fossil record is limited,” said study co-author Michal Kowalewski, curator of invertebrate paleontology at the Florida Museum. “But, thanks to efforts of paleontologists many of those rare fossils have been documented all around the world, finally giving us a chance to look at their evolutionary history in a more rigorous, quantitative way.”

“This new work builds a good case for the role of reefs in promoting the evolutionary diversification of crustaceans,” said David Jablonski, a paleontologist in the department of geophysical sciences at the University of Chicago who was not involved in the study. “We have to take their argument for the flipside of that story very seriously. The positive relation between reefs and crustaceans implies that the damage caused to reefs by human activities — from overfishing to ocean acidification — is likely to have cascading consequences for associated groups, including crustaceans.”

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Scorpion is Gondwana's Oldest Known Land Animal

A postdoctoral fellow from Wits University has discovered the oldest known land-living animal from Gondwana in a remote part of the Eastern Cape. Dr Robert Gess, from the Evolutionary Studies Institute at Wits, discovered the 350 million year old fossilised scorpion from rocks of the Devonian Witteberg Group near Grahamstown. This unique specimen, which is a new species, has been called Gondwanascorpio emzantsiensis.

His discovery has been published in the peer reviewed journal African Invertebrate on Wednesday, 28 August 2013.

Explaining his discovery, Gess said that early life was confined to the sea and the process of terrestrialisation - the movement of life onto land - began during the Silurian Period roughly 420 million years ago. The first wave of life to move out from water onto land consisted of plants, which gradually increased in size and complexity throughout the Devonian Period.

This initial colonisation of land was closely followed by plant and debris-eating invertebrate animals such as primitive insects and millipedes. By the end of the Silurian period about 416 million years ago, predatory invertebrates such as scorpions and spiders were feeding on the earlier colonists of land.

By the Carboniferous period (350 million years ago), early vertebrates - our four-legged ancestors -had in turn left the water and were feeding on the invertebrates. Although we knew that Laurasia -the single northern landmass then comprising what is today North America and Asia - was inhabited by diverse invertebrates by the Late Silurian and during the Devonian, this supercontinent was at the time separated from the southerly positioned Gondwana by a deep ocean.

"Evidence on the earliest colonisation of land animals has up till now come only from the northern hemisphere continent of Laurasia, and there has been no evidence that Gondwana was inhabited by land living invertebrate animals at that time," explained Gess.

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Earth Worm Trace Fossils Just After the KT/K-Pg Boundary

Fossil Worm Burrows Reveal Very Early Terrestrial Animal Activity and Shed Light on Trophic Resources after the End-Cretaceous Mass Extinction

Authors:

1. Karen Chin (a)
2. Dean Pearson (b)
3. A. A. Ekdale (c)

Affiliations:

a. Department of Geological Sciences and Museum of Natural History, University of Colorado Boulder, Boulder, Colorado, United States of America

b. Pioneer Trails Regional Museum, Paleontology Department, Bowman, North Dakota, United States of America

c. Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah, United States of America

Abstract:

The widespread mass extinctions at the end of the Cretaceous caused world-wide disruption of ecosystems, and faunal responses to the one-two punch of severe environmental perturbation and ecosystem collapse are still unclear. Here we report the discovery of in situ terrestrial fossil burrows from just above the impact-defined Cretaceous-Paleogene (K/Pg) boundary in southwestern North Dakota. The crisscrossing networks of horizontal burrows occur at the interface of a lignitic coal and silty sandstone, and reveal intense faunal activity within centimeters of the boundary clay. Estimated rates of sedimentation and coal formation suggest that the burrows were made less than ten thousand years after the end-Cretaceous impact. The burrow characteristics are most consistent with burrows of extant earthworms. Moreover, the burrowing and detritivorous habits of these annelids fit models that predict the trophic and sheltering lifestyles of terrestrial animals that survived the K/Pg extinction event. In turn, such detritus-eaters would have played a critical role in supporting secondary consumers. Thus, some of the carnivorous vertebrates that radiated after the K/Pg extinction may owe their evolutionary success to thriving populations of earthworms.

Evidence of Eusocial Insects from the Hettangian/Sinemurian Jurassic of China?

Novel insect traces on a dinosaur skeleton from the Lower Jurassic Lufeng Formation of China

Authors:

1. Lida Xing (a, b)
2. Eric M. Roberts (c)
3. Jerald D. Harris (d)
4. Murray K. Gingras (e)
5. Hao Ran (f)
6. Jianping Zhang (a)
7. Xing Xu (g)
8. Michael E. Burns(b)
9. Zhiming Dong (g)

Affiliations:

a. School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China

b. Department of Biological Sciences, University of Alberta, 11455 Saskatchewan Drive, Edmonton, Alberta T6G 2E9, Canada

c. School of Earth and Environmental Science, James Cook University, Townsville, Qld 4811, Australia

d. Physical Sciences Department, Dixie State College, 225 South 700 East, St. George, Utah 84770, USA

e. Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada

f. Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection (Guangxi Normal University), Ministry of Education, Guilin 541004, China

g. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China

Abstract:

Dense networks of burrow-like traces on the surfaces of bones are preserved on a partial skeleton of a prosauropod dinosaur (cf. Yunnanosaurus) from the Lower Jurassic Lufeng Formation in Yunnan, China. The traces, which gently meander across and, in places, shallowly excavate the surfaces of several axial and appendicular skeletal elements (total cumulative length over 29 m) consist of simple burrows, Y-shaped branches, overlapping intersections, and chambers. This unusual network is morphologically most similar to foraging traces of eusocial insects, particularly termites. Comparisons of known continental ichnofossils, demonstrate the novelty of this trace, which thus pertains to a new ichnotaxon, Taotieichnus orientalis ichnogen. et ichnosp. nov. Taotieichnus orientalis most closely resembles subaerial foraging galleries constructed of mud or carton (saliva and faecal material mixed with soil or partially digested wood particles) and produced by a range of subterranean termites. Periodic, possibly seasonal, use of carrion as a nutrient source, and the construction of carton foraging galleries over decomposing vertebrate carcasses, is a known, but little documented, dietary supplement for some xylophagus, neotropical termite species. These Early Jurassic traces constitute the earliest evidence of eusocial insect foraging behavior, and suggest that a possible adaptive radiation of stem- or crown-group termites as foragers—or, at least, opportunistic decomposers—of animal carcasses had already occurred by the Early Jurassic.

A New Wiwaxia Fossils From Cambrian China

New Wiwaxia material from the Tsinghsutung Formation (Cambrian Series 2) of Eastern Guizhou, China

Authors:

1. HAI-JING SUN (a)
2. YUAN-LONG ZHAO (a)
3. JIN PENG (a)
4. YU-NING YANG (a)

Affiliation:

a. College of Resources and Environmental Engineering, Guizhou University, Guiyang 550003, People's Republic of China

Abstract:

Wiwaxia is an extinct early metazoan with uncertain affinities, which is well represented in strata of Cambrian Series 2–3 age. Well-preserved representatives of Wiwaxia are known from the Burgess Shale Biota and the Kaili Biota. Here, new material of Wiwaxia corrugata (Matthew, 1899) is reported from the upper part of the Tsinghsutung Formation (Cambrian Series 2) near Balang Village, Guizhou Province, China. These specimens have a close evolutionary relationship to Wiwaxia taijiangensis Zhao, Qian & Lee, 1994 from the overlying Kaili Formation. New Wiwaxia material from the Tsinghsutung Formation and observations of specimens with articulated individuals from the Kaili Formation suggest that Wiwaxia taijiangensis should be a junior synonym of W. corrugata. A new study indicates that W. corrugata has a wide geographic distribution, a short geological history and evolutionary uniqueness and provides new data on taphonomy of this genus.