A researcher from the Swedish Museum of Natural History in collaboration with colleagues from the University of Fribourg (Switzerland) and the Instituto Antártico Argentino based in Buenos Aires (Argentina), has published a scientific paper which provides details of the first fossil frog to have been found on the continent of Antarctica.
A Fossil Frog from Seymour Island
The fossils, consisting of a partial ilium and a bone from the skull which were found in Eocene-aged deposits on Seymour Island, resemble an extant lineage of frogs known as helmeted frogs (family Calyptocephalellidae). Until this discovery, no Cenozoic ectothermic continental tetrapods (amphibians and reptiles), had been documented from Antarctica. The tiny frog fossils suggest that around 40 million years ago, climatic conditions at high latitudes in the southern hemisphere were still mild enough to support “cold-blooded” amphibians.
A Life Reconstruction of the Helmeted Frog Found on the Antarctic Peninsula (Seymour Island)
Life reconstruction of the frog genus described from the Eocene of Antarctica.
Picture credit: Pollyanna von Knorring / Swedish Museum of Natural History
Studying Eocene Freshwater Habitats
Writing in the academic, on-line journal “Scientific Reports”, the researchers conclude that some Eocene freshwater habitats in Antarctica provided habitats that were favourable for cold-blooded (ectothermic) vertebrates such as frogs. Antarctica was much milder than it is today, the warmest months of the year averaging around 13 degrees Celsius whilst temperatures in the winter would have dropped to below an average of 4 degrees Celsius. Frogs were present in freshwater ecosystems at a time in the history of Antarctica where ice sheets had formed in upland areas towards the interior of the continent.
Views of the Fragmentary Ilium from Seymour Island
Ilium (NRM-PZ B282) of Calyptocephalella sp. from Seymour Island, Antarctica. Ilium in lateral (a), medial (b), ventral (c) and dorsal (d) views. Scale bar equals 1 mm.
Picture credit: Swedish Museum of Natural History
The Discovery of Fossil Frog Remains
The fossil frog remains were collected during three joint Argentinian-Swedish expeditions to Seymour Island in the southern hemisphere summers 2011–13. The bone fragments were concentrated from dry-sieved sediment samples. The closest living relatives of the Eocene specimen are limited to the Chilean Andes (Calyptocephalellidae). With the discovery of the fossils on Seymour Island, the researchers conclude that these types of helmeted frog were much more widespread across what remained of Gondwana during the Eocene.
The material is housed in the palaeozoological collection of the Swedish Museum of Natural History, Stockholm.
The scientific paper: “First fossil frog from Antarctica: implications for Eocene high latitude climate conditions and Gondwanan cosmopolitanism of Australobatrachia” by Thomas Mörs, Marcelo Reguero and Davit Vasilyan published in Scientific Reports.
Researchers from the Florida Museum of Natural History (Florida University) and the Natural History Museum of Los Angeles County have published a scientific paper describing a portion of a left humerus (upper arm bone), discovered in north-western Puerto Rico that represents the oldest fossil remains of a frog ever found in the Caribbean. The tiny bone, it measures less than one centimetre in length, has been assigned to the genus Eleutherodactylus, colloquially called coquí frogs in reference to the distinctive “coe-kee” call made by the males of some species as they seek to attract a mate.
The Fossilised Humerus is Compared to the Humeri of Extant Genera
Comparisons of the fossil specimen to representatives of each extant Caribbean frog genus as well as each Caribbean subgenus of Eleutherodactylus (Eleutherodactylus, Euhyas, Pelorias and Schwartzius). Note various views LACM 162445 anterior, medial, posterior and lateral views. Scale bar = 1 mm.
Picture credit: Blackburn et al (Biology Letters) with additional annotation by Everything Dinosaur
The authors of the scientific paper comment that it is fitting to have discovered this fossil bone in Puerto Rico, as the coquí is one of the national symbols associated with this tropical island.
From the San Sebastian Formation and Estimated to be 29 Million Years Old
The tiny bone was found by co-author Jorge Velez-Juarbe (Natural History Museum of Los Angeles County), in a mudstone layer of the San Sebastian Formation, exposed by a river (Rio Guatemala), in the north-western portion of the island, close to the town of San Sebastián. The mudstone layer has been dated to 29.47 million years ago (+/- 300,000 years) and it represents an estuarine environment. Other vertebrate fossils associated from this location include turtles, gharials and rodents.
Commenting on the discovery, lead author David Blackburn (Florida Museum of Natural History), stated:
“It’s a national treasure. Not only is this the oldest evidence for a frog in the Caribbean, it also happens to be one of the frogs that are the pride of Puerto Rico and related to the large family Eleutherodactylidae, which includes Florida’s invasive greenhouse frogs.”
A Life Reconstruction of the Prehistoric Frog
The 29-million-year-old Eleutherodactylus frog life reconstruction. Based on measurements of the partial humerus, the scientists estimate the extinct frog to have measured around 4 centimetres in length.
Picture credit: Jorge Velez-Juarbe (Natural History Museum of Los Angeles County)
Looking for Evidence of Oligocene Frogs
Scientists studying data from phylogenetic assessments had postulated that these types of frogs had established themselves in the Caribbean during the Oligocene but until now there was no fossil evidence to support this line of research. The bones of frogs tend to have a poor preservation potential. They are small, light and any corpse would very likely, quickly decompose in the hot, humid tropical conditions.
Possibly first arriving in the Caribbean by rafts of vegetation displaced from South America, these small tree frogs in the genus Eleutherodactylus, which encompasses some 200 species, dominate the Caribbean today. Coquís differ from most other frogs as they usually do not lay their eggs in water. They do not have a hatching tadpole stage, instead the tadpole stage takes place within the egg, the male carefully tending the nest and ensuring that the eggs remain moist. When the eggs hatch, the young emerge as fully formed froglets.
A Male Coquí Frog Protecting a Clutch of Eggs
A male coquí frog protecting a clutch of eggs.
Picture credit: Jorge Velez-Juarbe (Natural History Museum of Los Angeles County)
Everything Dinosaur acknowledges the assistance of a media release from the University of Florida in the compilation of this article.
The scientific paper: “The earliest record of Caribbean frogs: a fossil coquí from Puerto Rico” by David C. Blackburn, Rachel M. Keeffe, María C. Vallejo-Pareja and Jorge Vélez-Juarbe published in Biology Letters.
New Study Might Help Explain Why Crocodilians Survive Extinction Events
A team of scientists including researchers from the Natural History Museum (London) and the Milner Centre for Evolution (Bath University), have provided fresh insight into how crocodilians are able to survive dramatic changes in climate that cause extinctions amongst other vertebrates. The researchers conclude that extant crocodilians are part of a lineage of great survivors that might cope better than most other large animals when having to face a world with a continuing rise in average annual temperature.
Crocodilians Might Be Better Able to Cope with Global Climate Change
An anterior view of the skull of an estuarine crocodile photographed in the Grant Museum, London. The largest reptile on Earth, the estuarine crocodile (Crocodylus porosus) from south-east Asia is also known as the saltwater crocodile or saltie. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Crocodiles Surviving Mass Extinction Events
Writing in the Biological Journal of the Linnean Society, the scientists suggest that the ability of crocodilians to survive mass extinction events could be due in part, to their approach to reproduction. Modern crocodiles are an ancient lineage. They are grouped into the clade Neosuchia, which first arose in the Late Cretaceous, although related forms are even older, such as the Pseudosuchia, which first arose some 250 million years ago.
Neosuchian crocodilians have therefore survived numerous extinction events, including two mass extinctions, the first that occurred approximately 66 million years ago and saw the demise of their fellow archosaurs – the Dinosauria and the Pterosauria as well as many other different types of organism. Then, there was a second, albeit smaller, mass extinction event towards the end of the Eocene approximately 33.9 million years ago.
The Relationship Between Size of Female Crocodilians and Where They are Found
The relationship between distribution patterns and body size has been recorded and analysed in many kinds of endothermic (warm-blooded) animals. However, evidence to support the idea that there is a correlation between where in the world animals are found and the size of females in ectotherms (cold-blooded animals), has been generally, not that well documented.
No extensive study between the global distribution of crocodiles and the body mass of females has been carried out. The research team examined the relationship between latitudinal distribution and body mass in twenty living species of crocodilians and studied seven other important factors in reptile reproduction such as size of the egg clutch laid, the number of successful hatchings per nest, incubation length and incubation temperature.
The Average Size of a Female of the Species was Correlated Against the Latitudinal Midpoint of Where that Species is Found
Plotting the average size of female crocodiles against where the species is found.
Picture credit: Lakin et al (Biological Journal of the Linnean Society)
Statistical Analysis
Using statistical analysis, the study showed that, in general, smaller species of crocodilian tend to live at low latitudes (close to the equator). Larger species tend to live at higher latitudes, still in the tropics but further away from the equator. This is the first study to propose a relationship between where in the world crocodilians live and the effect on adult female body mass.
Previous studies looking at the how well adapted crocodilians are have cited diet, their aquatic nature and their behaviours as factors in helping these types of creatures to survive dramatic changes in environmental conditions. However, this study also identified a unique aspect of crocodilian reproductive biology that may also be a significant factor.
Crocodilians have no sex chromosomes, just like many types of tortoises and turtles, instead the sex of the hatchlings is determined by the temperature at which the eggs are incubated. Both crocodiles and most turtles have a threshold temperature at which the ratio of males to females is roughly equal in any given clutch.
Temperature and Crocodiles
In crocodilians, the higher the temperature of the clutch, then more males will be produced. For those members of the Order Chelonia (Testudines), that are biologically subject to temperature controlled sexual determination, the opposite is true, higher temperatures result in more female hatchlings. The increase in average global temperatures is already having a dramatic impact on turtle populations. Our warming world is resulting in some hatchling populations being comprised of 80% females. Such an imbalance in animal populations could have a dramatic impact on those species affected.
Environmental Temperature Affects the Sex of Crocodilians and Most Members of the Order Testudines
In most turtles/tortoises sex of the individual is dependent upon temperature of the clutch. This environmental factor determines the sex of all crocodilians. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The diagram (above), demonstrates that in crocodilians the higher the temperature of the nesting environment, more males are likely to be produced from the nest. For most members of the Order Testudines, the reverse is true – warmer temperatures will lead to more females.
The research team wanted to assess the impact of this aspect of crocodilian reproductive biology on their ability to cope with the impact of climate change.
Twenty Different Species of Crocodile Studied
In total, twenty different species of crocodiles were assessed to see if there was a correlation between their latitude and a variety of biological traits such as female body size and incubation temperature. The researchers conclude (with some exceptions), that smaller species do tend to live close to the equator, whilst larger species generally live in more temperate climates at higher latitudes. Intriguingly, they found that, in contrast to most Testudines, the threshold incubation temperatures don’t correlate with the latitude.
Whilst turtles are critically endangered by the increase in temperatures due to climate change, this research indicates that crocodiles and their close relatives may be slightly more resilient because of the ways they look after their young. For example, sea turtles always return to the same beach to nest and lay eggs regardless of the local environmental conditions, leaving their young to hatch alone and fend for themselves.
The authors hypothesise that the geographical location of the nest doesn’t affect the incubation temperatures as much as in turtles because crocodilians select their nesting sites carefully and bury their nests in rotting vegetation or earth which insulates them against temperature fluctuations.
However, despite being around virtually unchanged for 90 million years, crocodilians are still threatened and several species are critically endangered. Unless adequate steps are taken to safeguard these species, they too, will sadly, end up going the same way as the dinosaurs.
Keystone Species
Lead author of the study, PhD student Rebecca Lakin at the Milner Centre for Evolution (University of Bath) stated:
“Crocodilians are keystone species in their ecosystems. They are amongst the last surviving archosaurs, a group that once inhabited every continent and has persisted for at least 230 million years”.
A model of a crocodile with an articulated lower jaw.
Rebecca added:
“They show a remarkable resilience to cataclysmic climate change and habitat loss, however half of all living crocodile species are threatened with extinction and the rate of vertebrate species loss will soon equal or even exceed that of the mass extinction that killed the dinosaurs. Whilst their parenting skills and other adaptations brace them for climate change, they aren’t immune. They are still vulnerable to other human-induced threats such as pollution, the damming of rivers, nest flooding and poaching for meat or skin. Climate change could encourage these great survivors to relocate to other areas that are close to densely human populated areas, putting them at even greater threat.”
Everything Dinosaur acknowledges the assistance of a media release from the Milner Centre for Evolution in the compilation of this article.
The scientific paper: “First evidence for a latitudinal body mass effect in extant Crocodylia and the relationships of their reproductive characters” by Rebecca J Lakin, Paul M Barrett, Colin Stevenson, Robert J Thomas and Matthew A Wills published in the Biological Journal of the Linnean Society.
These might be challenging times for us humans (Homo sapiens), what with all the concerns about the coronavirus outbreak, but at least for some animals it is business as usual. We have frogspawn in our office pond! The first eggs were laid in the early morning of the 19th March. We normally have frogspawn around the third week of March in our part of the world, the date of laying can vary by a couple of weeks, depending on the weather and the type of winter we have had. However, the spawning usually takes place around this time of year (third week of March).
Frogspawn is Spotted
The First Frogspawn Spotted in the Office Pond Early on the 19th March 2020
The first batch of frogspawn laid in the office pond (March 19th 2020). The photograph was taken a few minutes after 8am in the morning. From the size of the frogspawn we think that these are the eggs from a single female and that they had only just been laid.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Common Frog (Rana temporaria)
We have counted a total of seven frogs in the pond, the majority were males. We tend to have the males arriving first and the females taking up residence a little time later (after all, the females tend to be pounced upon as soon as they enter the pond). The frogs are all Common frogs (Rana temporaria), their name is a bit of a misnomer these days, as like many amphibians, they are becoming increasingly rare.
More Frogspawn was Laid that Morning (March 19th 2020)
More frogspawn laid on the morning of 19th March 2020. Team members at Everything Dinosaur estimate that the egg masses represent the eggs from two or three females. We shall continue to carefully monitor the pond (taking care not to disturb the frogs too much), to see if more eggs will be laid.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
As we cope with the current restrictions on our lives due to the coronavirus crisis, we will be able to observe how the tadpoles are getting on – something for us to think about in these challenging times. At least the frogs are behaving as normal, for them at least, it is business as usual.
New Study Suggests Climate Change Could Reduce Lifespan Amongst Hundreds of Species
Researchers from Queen’s University Belfast and Tel Aviv University (Israel), have carried out one of the most comprehensive studies to date to better understand what affects life expectancy among all living vertebrates in the world. The study’s conclusions not only challenge a long-accepted theory about the lifespan of organisms, but also provide a new perspective on climate change – that global warming could have a huge impact on the life expectancy among ectothermic animals such as reptiles and amphibians.
Amphibians such as Frogs Could Be Exceptionally Vulnerable to the Consequences of Global Warming
Cold-blooded animals such as frogs may be exceptionally vulnerable to climate change.
Picture credit: Queen’s University Belfast
Global Warming
The “rate of living” theory has long been accepted as an explanation as to why organisms age. According to this theory, the faster the metabolic rate the shorter the lifespan. Live fast and die after a relatively short period, in other words the “faster” the species lives in terms of the speed of its internal body functions and how quickly they start to reproduce, or how “slowly” in terms of these internal body functions and of lower reproductive rates, will determine the lifespan.
Research into How Organisms Age
This hypothesis helps to explain why some vertebrates such as frogs and reptiles may only live for a few months, whilst other species such as elephants, the Greenland shark and turtles can live for a very long time.
Giant Tortoises Can Live for Over a Hundred Years
The Rebor 1:6 scale Pinta Island tortoise “Lonesome George” in oblique lateral view. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The image (above) shows the Rebor 1:6 scale giant tortoise model “Lonesome George”.
The Hotter the Environment – The Faster the “Rate of Living”
Until now the theory had not been tested at a global scale with all land vertebrates and there were limitations with the range of species the theory was tested on. The scientists from Queen’s University and Tel Aviv University analysed data from over 4,100 land vertebrate species from across the planet to test the prevailing “rate of living” theory.
They discovered that “rate of living” does not affect aging rates, rejecting the previously accepted link between lifespan and metabolism.
Writing in the academic journal “Global Ecology and Biogeography”, the researchers found that rates of aging in cold-blooded organisms (ectotherms), including amphibians and reptiles are linked to high temperatures. These findings led the scientists to put forward an alternative hypothesis: the hotter the environment is, the faster the rate of living that in turn leads to more accelerated aging and a shorter lifespan.
Critical Implications
Commenting on the significance of this new study, co-author Dr Daniel Pincheira-Donoso, (School of Biological Sciences at Queen’s University Belfast) stated:
“Our findings can have critical implications for our understanding of factors that contribute to extinctions, especially in modern times when we are facing a worldwide decline of biodiversity, with cold-blooded animals being particularly endangered. Now we know that the life-expectancy of cold-blooded vertebrates is linked to environmental temperatures, we could expect to see their lifespans further reduced as temperatures continue to rise through global warming.”
A Pair of Common Frogs Mating (Rana temporaria)
A pair of mating frogs (2017). The long-term outlook for many species of amphibian including the Common frog (Rana temporaria) is not good.Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Amphibians the Most Threatened Class of the Animalia
According to date from the International Union for Conservation of Nature Red List (IUCN), some 30,000 species are currently threatened with extinction. This figure represents around 27% of all the species assessed. Amphibians are, on average, the most threatened Class, with 41% of species threatened. A press release from the Queen’s University Belfast states that nearly one in five of the world’s estimated 10,000 species of lizards, snakes, turtles, crocodiles and other reptiles are threatened with extinction.
PhD student, Gavin Stark, the lead author of the study (Tel Aviv University), explained:
“The link between lifespan in cold-blooded animals (amphibians and reptiles) and ambient temperatures could mean that they are especially vulnerable to the unprecedented global warming that the planet is currently experiencing. Indeed, if increasing ambient temperatures reduces longevity, it may make these species more prone to go extinct as the climate warms.”
Dr Pincheira-Donoso added:
“We need to further develop our understanding of this link between biodiversity and climate change. Only armed with knowledge will we be able to inform future policies that could prevent further damage to the ecosystem.”
The Scientific Paper
The paper entitled, “No evidence for the “rate-of-living” theory across the tetrapod tree of life” is published in the journal Global Ecology and Biogeography. Manuscript ID GEB-2019-0279.R4.
Everything Dinosaur acknowledges the assistance of a media release from Queen’s University Belfast in the compilation of this article.
Another busy week for Everything Dinosaur team members. A member of staff was at the London Natural History Museum recently, although they had a busy itinerary there was still time to enter the main gallery (the Hintze Hall) and to say hello to “Hope”, the enormous Blue Whale exhibit that replaced “Dippy” the Diplodocus in 2017. Suspended overhead, dominating the refurbished gallery, the Blue Whale skeleton (Balaenoptera musculus), symbolises the Museum’s focus on conservation and supporting efforts to save natural habitats and wildlife.
The Blue Whale Skeleton
The Spectacular “Hope” Blue Whale Exhibit in the Hintze Hall (London Natural History Museum)
The beautiful Blue Whale skeleton exhibit dominating the Hintze Hall at the London Natural History Museum. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
The Blue Whale Skeleton Measures 25.2 Metres Long
The skeleton measures 25.2 metres in length, it weighs some 4.5 tonnes and consists of 221 individual bones. Not all parts of the exhibit are real bone, some bones were missing from the right flipper and these have been replaced by 3-D printed mirror copies of the bones from the left flipper. Seeing the Diplodocus exhibit in the main gallery was always a highlight of any visit to the Museum. It became almost a ritual to say hello to “Dippy” on the way to a meeting or prior to visiting one of the various departments on site.
The Diplodocus exhibit was only a cast, a specimen that had been donated to the London Natural History Museum in 1905 by the Scottish-born billionaire Andrew Carnegie. “Dippy” was installed into the Hintze Hall in 1979, but finally removed in January 2017 to be replaced by the Blue Whale exhibit.
We will have to get used to saying hello to “Hope” instead.
Everything Dinosaur’s Top Ten Blog Posts of 2019 (Part 2)
Today, we conclude our review of the top ten blog posts written by Everything Dinosaur team members in 2019. We have produced a blog post for every day of the year and as a result we have covered a tremendous range of topics from new fossil discoveries, highlighting research, the introduction (and retirement) of prehistoric animal replicas, book reviews, artwork created by academic illustrators and scientific discoveries.
Here is our countdown of the top five.
5). Ngwevu intloko – New Dinosaur “Hiding in Plain Sight”
Over the summer, Everything Dinosaur published a wide range of articles. A new bizarre, shovel-mouthed duck-billed dinosaur (Aquilarhinus), was reported and news of a fast-running Triassic theropod from Switzerland (Notatesseraptor) broke. We had strange prehistoric parrots, an analysis of the cranial capacity of “parrot lizard” Psittacosaurus and herbivorous crocodylomorphs. However, number five on our list concerns the discovery of a new type of Triassic herbivorous dinosaur that was found in a museum cabinet.
Fossils once thought to represent an unusual specimen of Massospondylus (M. carinatus) in the collection of the University of Witwatersrand (South Africa), were assigned to their own genus. Student Kimberley Chapelle and colleagues identified a total of twenty-two characteristics that supported the establishment of a brand new dinosaur genus. The new dinosaur was named Ngwevu intloko, this member of the Sauropodomorpha had been hiding in plain sight within the vertebrate fossil collection of the University for more than three decades.
Views of the Skull of Ngwevu intloko
Views of the skull of Ngwevu intloko.
Picture credit: Kimberley Chapelle/University of Witwatersrand
4). Keresdrakon vilsoni – Toothless Pterosaur from an Ancient Desert Ecosystem
September and thirty days of blog posts covering stiff T. rex skulls and subsequently how the skull of T. rex may have helped it to keep cool, dinosaur model deliveries to hotels, the most complete dinosaur fossil from Japan (Kamuysaurus japonicus) and the Asian origins of Saurornitholestes, but our number four features a newly described species of pterosaur from Brazil.
Researchers, writing in the academic journal “Anais da Academia Brasileira de Ciências”, identified a new species of edentulous flying reptile that co-existed with the pterosaur Caiuajara and may have fed on its young. Described as part of a non-tapejarid lineage of pterosaurs outside the Tapejaromorpha, Keresdrakon provides a new perspective on the paleoecology of a Cretaceous desert environment.
Keresdrakon Life Reconstruction It Feeds on the Carcase of a Contemporary Dinosaur (Vespersaurus) whilst a Second Keresdrakon is Mobbed by Juvenile Caiuajara
Keresdrakon life reconstruction, feeding on the carcase of a Vespersaurus.
Picture credit: Maurilio Oliveira
An honourable mention to Cryodrakon boreas the first pterosaur to be described which is unique to Canada.
3). A Potential Terrestrial Tetrapod that May Not Have Gone onto Land
In October, Everything Dinosaur team members covered the amazing TetZooCon event in London, the naming of a new, basal carcharodontosaurian theropod from Thailand (Siamraptor suwati) and the reclassification of crocodiles in New Guinea. A team of researchers, writing in “Nature” put forward an intriguing new hypothesis that some of the first vertebrates that were capable of terrestrial locomotion may have never left the water. Parmastega aelidae was a sharp-eyed predator that may have ambushed invertebrates that ventured too close to the sea.
With eyes positioned towards the top of their heads, Parmastega was capable of observing life on land and potential prey without leaving the water.
Life in a Late Devonian Coastal Lagoon (Sosnogorsk, Russia)
Sosnogorsk lagoon with Parmastega aelidae hunting behaviour.
Picture credit: Mikhail Shekhanov for the Ukhta Local Museum
2). Unusual Styracosaurus Skull Might Change the Way New Dinosaurs are Identified
The first fossil evidence of feathered polar dinosaurs, plans to map extra-terrestrial space objects in a bid to prevent Earth impact events, limited edition dinosaur models, a new predatory dinosaur from Brazil – Gnathovorax cabreirai, all featured in October. A fossil ape from the Miocene of Germany, Poland’s first pliosaur, Rebor Komodo dragons, a new megaraptorid from “Down Under” and the discovery of a Styracosaurus skull that might just turn palaeontology on its head were also discussed. “Hannah” an asymmetrical Styracosaurus skull named after the pet dog of palaeontologist Scott Persons has cranial imperfections that could alter the way that scientists identify new species of dinosaur. Whoops, looks like there may have to be another revision of the Centrosaurinae.
Palaeontologist Scott Persons Poses with the Two “Hannahs” in His Life “Hannah” the pet dog and “Hannah” the Styracosaurus
Scott Persons with “Hannah” the Styracosaurus and his dog.
Picture credit: Scott Persons/University of Alberta
1). Asfaltovenator vialidadi – A New Basal Allosauroid from Argentina
Our blog articles this month have covered such varied topics as galloping crocodilians, 7,000 Facebook “likes”, the announcement of new for 2020 Papo prehistoric animal figures, dinosaur teeth replacement, how to distinguish teenage tyrannosaurs and Mimodactylus libanensis, a new toothy pterosaur from the Late Cretaceous of Lebanon.
However, since we started this top ten countdown with a fossil discovery from North America and despite the focus on asymmetrical dinosaurs, we shall conclude with a dinosaur from the opposite end of the Americas.
Asfaltovenator vialidadi from the Cañadón Asfalto Formation (Chubut Province, Patagonia) roamed South America perhaps as early as 170 million years ago. Its discovery is important, as most Middle Jurassic theropods are only known from quite fragmentary material and this dinosaur, described as a basal allosauroid, has traits linking it to both the allosauroids and the megalosauroids. The fossils suggest that the Allosauroidea and the Megalosauroidea evolved from a common ancestor.
A Life Reconstruction of the Newly Described Asfaltovenator vialidadi
Asfaltovenator life reconstruction. The theropod dinosaur shows a mix of anatomical characteristics linking the Allosauroidea and the Megalosauroidea.
Picture credit: Gabriel Lio/Conicet
Team members at Everything Dinosaur look forward to posting up more blog articles that help to work out taxonomic relationships within the Dinosauria and improve our understanding of ancient life still further in the coming months.
Everything Dinosaur’s Top Ten Blog Posts of 2019 (Part 1)
As this year draws to a close, it is time to reflect on all the work put into writing this web log by Everything Dinosaur team members. It is also an opportunity to look back and reflect on some of the news stories and articles that we have published over the last twelve months. Today, we start our look at the top ten articles that we have posted, the countdown from ten to number six. This list has been compiled based on the total number of comments made, emails received requesting further information, Facebook “likes” and comments, Pinterest shares and so forth.
So, without any further fuss, here is the first part of our top ten news stories for 2019.
10). Prehistoric Shark Named After Video Game Character
In January, Everything Dinosaur covered a story about the naming of a new species of Late Cretaceous prehistoric shark. Strange, unusually shaped shark’s teeth had been found preserved in some of the matrix associated with the famous “Sue” T. rex skeleton. The tiny teeth reminded the research team of the shape of a spaceship from the 1980’s video game Galaga. This was the inspiration behind the naming of this new species – Galagadon nordquistae.
Life Reconstruction of Galagadon nordquistae
A life reconstruction of the Late Cretaceous shark Galagadon nordquistae.
Early February saw the announcement of the discovery of a new, bizarre dicraeosaurid from Neuquén Province, Argentina. A single, cervical vertebra suggests that Bajadasaurus had a series of forward facing defensive spikes on its neck. A sauropod that carried its own set of Victorian railings around with it. Although, the fossil material is fragmentary, CollectA were quick of the mark and have created a stunning replica of this Early Cretaceous giant. Everything Dinosaur expects to have the CollectA Bajadasaurus replica in stock early in 2020.
A Silhouette Showing a Reconstruction of the Neck Vertebrae of Bajadasaurus and the CollectA Bajadasaurus Dinosaur Model
The bizarre cervical vertebrae of Bajadasaurus. In the silhouette illustration known fossil material is shown in white.
Picture credit: Gallina et al published in Scientific Reports and Everything Dinosaur
In March, a blog post was published recording the start of a huge collaboration between a number of European and American museums to explore and excavate an extraordinary, fossil-rich deposit located in the Badlands of Wyoming. The site has been nicknamed the “Jurassic Mile” and these Morrison Formation deposits have already yielded a treasure trove of dinosaur bones, fossil plants and dinosaur trackways.
Everything Dinosaur will be providing more details of the fossil discoveries in blog articles over the coming twelve months, but the site is so vast that it could be decades before all the fossil material has been collected and studied.
Palaeontologist Phil Manning Sitting Next to a Diplodocid Femur from the “Jurassic Mile”
Professor Phil Manning (The University of Manchester) poses next to the diplodocid femur.
Picture credit: Manchester University
7). New Kid on the Block – Homo luzonensis
The discovery of fragmentary fossil remains of a diminutive hominin on the island of Luzon in the Philippines gave the human family tree a jolt in 2019. The fossil material, dated to around 67,000 years ago, provides the earliest direct evidence of human inhabitation of the Philippines archipelago, but is Homo luzonensis, with its arboreal adaptations the descendant of a primitive African hominin that somehow migrated to south-eastern Asia or a more advanced hominin, perhaps related to Homo erectus that evolved and changed as it adapted to life on a heavily forested tropical island?
Professor Philip Piper – A Co-author of the Scientific Paper Published in April Holding a Cast of a Toe Bone
Professor Piper (Australian National University) holding a cast of a toe bone assigned to H. luzonensis.
Picture credit: Lannon Harley (Australian National University)
6). A Terrifying Trilobite (Redlichia rex)
In the summer, Everything Dinosaur published an article about the largest trilobite to have been discovered in Australia. A likely predator of other trilobites, this was a thirty-centimetre-long Cambrian terror. It was appropriately named Redlichia rex and was nicknamed “the king of the trilobites”. The fossil material comes from an exceptional Lagerstätte known as the Emu Bay Shale on Kangaroo Island, South Australia.
Around fifty different species of trilobite have been identified from this location. Intriguingly, the predatory and potentially cannibalistic Redlichia rex may also have been hunted, preserved coprolite and the injuries recorded on the exoskeleton of specimens hint at a much larger predator lurking in the shallow sea that once covered this part of Australia.
A Fossil Specimen and the New for 2020 CollectA Redlichia rex Trilobite Model
A Redlichia rex trilobite fossil and the new for 2020 CollectA model.
Picture credit: University of Adelaide/Everything Dinosaur
The naming of a new Cambrian predator inspired the model makers at CollectA to create a replica of Redlichia rex, we expect this figure to make its debut on the Everything Dinosaur website around the middle of next year. Prior to that event in 2020, we must first complete our chronicle of the top blog posts of 2019, we will conclude this feature tomorrow.
A study led by Royal Veterinary College staff has identified more species of crocodiles that can move quickly by adopting a galloping gait. In contrast, the closely related alligator and caiman, cannot manage more than a trot. Ironically, despite differences in locomotion, crocodiles and alligators can all move at approximately the same speed, which no more than around 11 miles per hour (4.9 metres per second). The ability to gallop and to use an even more extreme gait called a bound, is likely down to the size and build of the member of the family Crocodylia in question.
The Locomotion Study of Crocodilians Revealed Different Gaits
Crocodile (top) and Alligator (bottom). Forty-two individuals representing 15 species from the Crocodylia family were involved in the study. Picture credit: Everything Dinosaur.
Picture credit: Everything Dinosaur
Studying Living Crocodiles Provides Information about Extinct Crocodilians
Members of the Crocodylia employ almost the full range of quadrupedal footfall patterns (gaits) used by mammals. These forms of movement on land include asymmetrical gaits such as galloping and bounding. Researchers at the Royal Veterinary College set up video tracking cameras at the St Augustine Alligator Farm and Zoological Park in Florida (USA), in order to plot the movements of different crocodilians.
The St Augustine Alligator Farm houses a large number of different species and lots of different animals at various growth stages, it makes an ideal location at which to study crocodilian locomotion. The Park has been involved in numerous studies, including one conducted by University of Ohio researchers that looked at ways in which archosaurs may have helped to keep their brains cool. To read more about this research: T. rex had Air Conditioning.
In total the gaits and velocity of forty-two reptiles from fifteen species were studied.
Five Additional Crocodile Species Can Gallop and Bound
The researchers found that, as expected, larger animals moved relatively more slowly, with athletic ability decreasing as size and bulk increases. However, while many popular and scientific accounts previously assumed only a few species of crocodiles could gallop and bound, the scientists discovered that a further five species can in fact do so, including the critically endangered Philippine crocodile (Crocodylus mindorensis). This now means at least eight species in total can gallop and bound.
Professor John Hutchinson, (Royal Veterinary College), commented:
“We were really surprised at one major thing: despite the different gaits crocodiles and alligators use, they all can run about as fast. So why do some crocodiles choose to gallop? We suspect that bounding and galloping give small crocodiles better acceleration and manoeuvrability, especially useful for escaping from danger. It seems like alligators and caiman stand their ground rather than run away with an extreme gait.”
John Brueggen, Director of St Augustine Alligator Farm and Zoological Park, added:
“We have been witnessing these behaviours in many of our specimens over the years, but it was wonderful to finally formalise these observations in a scientific study.”
Triassic Origins?
The ancestors of today’s crocodilians tended to be small, much more terrestrial in habit and long-legged. Stem members of the Crocodylomorpha, such as Terrestrisuchus (illustrated below), needed to be fast runners in order to catch their prey and to avoid being eaten by larger predators. The researchers suggest that either that asymmetrical gaits are ancestral for Crocodylia and lost in the alligator lineage, or that asymmetrical gaits evolved within Crocodylia at the base of the crocodile branch of the family tree.
Terrestrisuchus – A Genus of Early Crocodylomorph from the Late Triassic
Terrestrisuchus – A genus of early crocodylomorph from the Late Triassic. The gaits and forms of locomotion seen in extant crocodilians could be a throwback to stem crocodylomorphs.
Recently, Everything Dinosaur published an article that examined another piece of research conducted by the scientists at the Royal Veterinary College, the paper focused on the giant caiman Purussaurus (P. mirandai), from the Late Miocene of Venezuela. This monstrous crocodilian evolved unique anatomical adaptations to help it move around on land.
The scientific paper: “Divergent evolution of terrestrial locomotor abilities in extant Crocodylia” by John R. Hutchinson, Dean Felkler, Kati Houston, Yu-Mei Chang, John Brueggen, David Kledzik and Kent A. Vliet published in the journal scientific research.
Everything Dinosaur acknowledges the assistance of a press release from the Royal Veterinary College in the compilation of this article.
With the advent of the new Rebor GrabNGo range, team members at Everything Dinosaur thought it would be appropriate to send out some Rebor Komodo dragon models, the first model to be introduced into this range, to customers so that they could see for themselves the attention to detail and quality of manufacture.
Several unboxing videos and reviews are in the process of being posted up on social media, so today we thought we would feature one such unboxing video from the “Plastic Prehistorica” YouTube channel.
The video itself lasts for a little under six and half minutes and it documents the unboxing of the new Rebor 1:6 scale GrabNGo Komodo dragon model.
Commissioning Cardboard for the Rebor Komodo Dragon
The narrator points out the Everything Dinosaur had to commission special cardboard packaging to accommodate this new figure. The model measures nearly half a metre in length, so we worked with our packaging suppliers to create a bespoke box, one that was double-walled so that this beautiful varanid could be protected in transit. After all, we don’t want our customers receiving a Komodo dragon that has been damaged in the post. We do all we can to ensure that our customers receive parcels that are well packed and that the figures inside have plenty of protection.
As part of our environmental policy, all the cardboard boxes that we commission are made from 60-70% recycled material. Only the outer face of our cardboard boxes is made from new wood pulp, this in turn is sourced from sustainable managed forests.
An Unboxing Video
In the unboxing video, the narrator highlights the point that producing models of endangered animals helps to raise awareness about their plight. Everything Dinosaur has ensured that the current conservation status of the Komodo dragon has been highlighted in the company’s promotional materials. On the subject of materials, Everything Dinosaur is currently working towards 100% recycling of all waste paper and cardboard at the company.
The Komodo Dragon Model (1:6 Scale Replica)
A still from the video showing a close-up view of the Komodo dragon model. The hand provides a scale.
Picture credit: Plastic Prehistorica
The Rebor Komodo Dragon Could Also Represent Megalania
In this informative video, the narrator comments that this figure could also represent Megalania, a giant, extinct varanid known from the Pleistocene of southern Australia. The actual size of Megalania is disputed, however, size estimates based on fossilised vertebrae suggest a length of between five and seven metres for this lizard. If this is the case, then the Rebor replica would represent a 1:12 scale model or thereabouts of Megalania.
A Close-up View Highlighting the Detailing on the Komodo Dragon Figure
Holding the new Rebor GrabNGo Komodo dragon replica, the hand provides a scale.
Picture credit: Plastic Prehistorica
The Plastic Prehistorica YouTube channel is full of informative and helpful prehistoric animal and dinosaur model reviews, to visit the channel: Plastic Prehistorica on YouTube.
To view the Rebor 1:6 scale Komodo dragon model and the rest of the figures in the Rebor range: Rebor Models and Replicas.
