Baby Sauropod Trackways Reported from South Korea

The National Heritage Centre under the National Research Institute of Cultural Heritage of the South Korean Government announced this week that more evidence of the country’s dinosaur past had been discovered.  South Korea is fast building a reputation for exceptional Mesozoic body and trace fossils, a number of important finds have already been studied but this new discovery may shed light on the ontogeny of dinosaurs (the development of individuals – how dinosaurs grew).

A number of discoveries have been made in South Korea recently, to read more trace fossils found in this country: Two-toed footprints found in Korea, evidence of Dromaeosaurs.

Dinosaur Trackways

A series of fossilised trackways have been found in Euiseong County, North Gyeongsang Province in the south-east of the country.  These well preserved trace fossils seem to show the footprints of two small sauropod dinosaurs, possibly juveniles.  The fossils have been dated to the Cretaceous, around 110 million years ago (Albian faunal stage).

In total, 61 sauropod footprints have been found, stretching across 4.25 metres, making this the longest fossil trackway of baby dinosaurs found to date.  The footprints were made as these small dinosaurs, wandered across muddy land, the area is criss-crossed with other trackways made by dinosaurs, some of which can be seen in the diagram.

The direction of travel is difficult to make out in the picture, although the sauropod trackway on the left, indicates that this animal was travelling from the top of the picture to the bottom, the other trackway is too unclear in this picture to make out the direction of travel.  The lack of any object such as ruler or pencil to provide scale, makes it difficult to interpret the evidence.  It is almost impossible to relate any trace fossils such as footprints to a particular genus, although the imprints are typical of titanosaurids (a branch of the sauropod family that was relatively common in the Southern Hemisphere during the Cretaceous).

It is not known what sort of titanosaur made these trackways, or indeed if it was a titanosaur, as the morphology of the animal may change as they grow bigger.  titanosaurs were long-necked, heavy set, herbivorous dinosaurs.  A typical titanosaur was Saltasaurus (a genus of titanosaur known from South America).

Saltasaurus – a Typical Titanosaur

Saltasaurus – a titanosaur.

Picture credit: Everything Dinosaur

To view a range of long-necked dinosaur models: Dinosaur and Prehistoric Animal Models.

Little is known about the ontogeny of dinosaurs, how animals such as titanosaurs could hatch from an egg no bigger than a football and grow into huge beasts over 20 metres long and weighing tens of tonnes.  Certainly, the titanosaurs represent some of the largest land animals ever to have lived and giants like Paralititan (Egypt), Argentinosaurus and Antarctosaurus (South America) could perhaps exceed 30 metres in length and weigh upwards of 100 tonnes.

Interpreting these fossil trackways are complicated due to the lack of other fossil evidence related to baby dinosaurs.  Adult titanosaur footprints are easily distinguished from other sauropod footprints such as diplodocids and brachiosaurids by their relatively wider gait, but very little is known about how dinosaurs grew and matured.  Perhaps, if these tracks were made at the same time, this might indicate that juveniles stayed together in a creche for protection, although any such deductions are highly speculative given the evidence from the fossil record discovered to date.

The Government of South Korea has applied to UNESCO for part of the country’s coastline where Cretaceous sediments are exposed to be given World Heritage status.  This would give this area the same preservation status as other natural wonders such as the Great Barrier Reef off Australia.

To read more: Korea makes bid for World Heritage status for Cretaceous coastline.

Scientists Identify Probable Cause of Strange Marks on Dinosaur Bones

Palaeontologists have long been perplexed by dinosaur fossils with missing pieces – sets of teeth without a jaw bone, dinosaur bones that are pitted and grooved, even bones that are half gone. Now a Brigham Young University study has put forward a thesis that attempts to identify the culprits: ancient insects that munched on dinosaur bones.

Dinosaur Bones

Brigham Young University professor Brooks Britt will publish his study of these dinosaur bone-eating bugs in the May edition of the scientific journal “Ichnos”.  An ichnologist is a scientist who specialises in studying trace fossils, fossils that preserve the activity of animals, such as their tracks, trails, burrows and such like.  Britt’s idea for this study came when he first noticed the unique markings on the bones as an undergraduate studying at the University.

“As students we noticed these marks and thought it might be due to algae or insects and we started calling them ‘bug bites,’ just for fun,” Britt said.

Studied Insect Traces

Years later, current Brigham Young student Anne Dangerfield also wondered about the markings and teamed up with Britt to investigate the cause. They studied insect traces on the 148-million-year-old remains of a Camptosaurus, a plant-eating specimen discovered in Medicine Bow, Wyoming in 1995.

“I knew this trace was something different because I had been looking at fossil termite traces all summer, so I knew we needed to check it out,” Dangerfield said.

Their analysis revealed that beetles, from the family entomologists call Dermestidae, left the markings on the Camptosaurus. dermestid beetles still exist today and are typically brown or black, oval-shaped and feed on flesh, hair, skin or the horns of carcasses.

An Illustration of a Camptosaurus

“Bent Lizard” to scale.  The bones of Camptosaurus were studied.

Picture credit: Everything Dinosaur

The groove cut into the anterior of a vertebra has been made by a dermestid beetle larva.

For models and replicas of prehistoric animals: Dinosaur Models and Figures.

By studying the habitat of modern species of dermestid beetle, the team were able to make assumptions about the climate in the Late Jurassic, the time when the Camptosaurus lived.  Information about the beetle’s typical habitat reveals the climate at the time of the Camptosaurus’ death probably had 60-80 percent relative humidity and a temperature of 77-86 F. By comparison, the average yearly temperature in Medicine Bow is now 43.5 F.

When the dinosaur died near what is now Medicine Bow, the carcass was consumed by other insects. The beetles then infested the Camptosaurus within months of its death.

An Insight into an Ancient Climate

In addition to shedding light on Wyoming’s ancient climate, Dangerfield and Britt’s work shows dermestid beetles existed much earlier than previously thought. The traces on this Camptosaurus predate the oldest body fossils for these beetles by 48 million years.  Insect fossils are particularly rare.  Their delicate bodies are not easily fossilised, although a number are trapped in tree resin, which under the right circumstances can form amber, allowing scientists to examine the organic remains trapped inside in minute detail.  With beetles, occasionally entire animals are preserved but more often it is an isolated wing sheath, the hard carapace that is discovered preserved as a fossil.

“This information gives us an idea of the environment during the Jurassic period and the evolution of insects,” Dangerfield commented.

Analysing the Markings on the Bones

To analyse the markings on the bones, Britt went to his family dentist for moulding materials, allowing Britt to more quickly create replicas of the bone traces to work with.

He took the castings back to University’s Earth Science Museum where he used an electron microscope to look at the mandible markings in the bone, examining eating patterns and the width between the teeth marks. Britt and Dangerfield compared the marks to information about the mandibles of moths, termites, mayflies and dermestid beetles – all known to consume bone – to determine the identity of the insect.

“Other people have thought they have seen dermestid beetle marks, or they have interpreted termite marks as dermestids, but this paper provides a guide to identifying insects from the bone traces,” the professor said.

Britt and Dangerfield continued their research by looking at more than 7,000 bones from various quarries and found that insect traces on dinosaur bones are quite common, but dermestid beetle traces were found only on the Camptosaurus skeleton from Medicine Bow.

“Dr Britt’s work is really exciting and delves into unique aspects of palaeobiology that few scientists have yet explored,” said Eric Roberts, an expert in dinosaur decomposition who teaches at South Africa’s University of the Witwatersrand. “Insects are among the most diverse and abundant organisms on the planet, yet we know next to nothing about the fossil record of insects because of their extremely limited preservation potential.”

The above article has been compiled using material from Brigham Young University (2008, May 6). Dinosaur Bones Reveal Ancient Bug Bites.

Smuggled Fossils Returned Home to Buenos Aires

Smuggled fossils returned to Argentina. In a cultural repatriation ceremony held last week nearly 4 tonnes of fossils were returned to Argentina by US Customs and Immigration Enforcement officials who had seized the items in raids back in 2006.

The fossils, believed to date from the Mesozoic era,  otherwise known as the Age of Reptiles, include an unspecified number of dinosaur eggs, plus shell fragments, fossilised pine cones and rare fossil prehistoric arthropods.  They were seized during a raid on a fossil dealer at the 2006 Tucson Gem and Mineral show.  The US Customs and Immigration officials were following a lead provided by Interpol, a reflection on the sad fact that the smuggling of rare artefacts such as fossils is an international business, one that is growing all the time.

The American officials raided a vendor at the show and subsequently impounded a number of other specimens at a nearby warehouse, suspecting that these objects had been illegally imported into the USA.

Posing as buyers, United States Customs officials conducted surveillance, taking photos of suspicious specimens and making detailed notes about the artefacts for sale.  Using the evidence that the team had gathered a federal warrant was issued and the consignment of fossils impounded.

Lisa Fairchild, the special agent supervising the case, said at the time that the agency considered the fossils priceless.

“It’s the property of another government and it can’t be replaced,” she commented.

USA Customs issued a statement to coincide with the official ceremony handing the fossils back to the Argentine Government stating that the investigation is continuing.  Julie Myers, Assistant Secretary for the USA Customs department stated:

“We think these historical artefacts rightly belong to the people of Argentina, so I’m very proud to be able to formally hand them back”.

Unfortunately, the smuggling of fossils and other rare items out of countries like Argentina, China and Thailand is a common occurrence.  State authorities are attempting to clamp down on such activities, however the relative lack of specialist knowledge hampers many such investigations.  In addition, the rapid rise in auction prices for rare fossils has added greater impetus to illegal smuggling of such items.

There have been a number of cases recently concerning the smuggling of Mesozoic fossils, including a number of incidents involving the smuggling of rare titanosaur eggs.  A number of consignments have been seized by Government authorities, many contained complete or nearly complete eggs believed to have come from a titanosaur nesting site in Argentina.  It is not entirely clear which genus of dinosaur may have laid the eggs but it is likely they came from a dinosaur such as Saltasaurus.

Fossils of Saltasaurus have been found in Argentina and Uruguay, an extensive nesting site associated with this animal was unearthed in Patagonia (southern Argentina).  Fossil trackways indicate that Saltasaurus lived in herds.  The eggs were about the size of footballs, the animals had excavated shallow holes, then laid their eggs before covering them with sand and vegetation, in a similar fashion to American Alligators.

An Illustration of the Titanosaur Saltasaurus (Scale Model)

An illustration of a typical titanosaur.

Picture credit: Everything Dinosaur

The picture above is of a scale model of the titanosaur, Saltasaurus to view the titanosaur models within the Everything Dinosaur range: Dinosaurs and Prehistoric Animal Models.

Criminal Gangs

Much of this activity is being directed by organised criminal gangs, however, fraud in the sell of fossils and other items such as gemstones and minerals is quite common.  Whether this is due to a genuine mistake on behalf of the vendor or whether it is a deliberate attempt to mislead the buyer is often unclear.

A typical example of how people can be deceived occurred just the other day when one of the Everything Dinosaur team members went to the Post Office to drop off some parcels ready for despatch.

As the parcels were being processed and receipts printed off, the Post Office Manager mentioned that his partner had recently purchased a necklace that contained a gemstone made from Dinosaur poo that was over 40 million years old.  The technical term for fossilised droppings is coprolites and indeed there are a number of legitimate sources of such items.  The coprolite specimens are usually small fragments that have been further cut by diamond bladed saw, then shaped and polished to produce a shiny, smooth gemstone.

It can be difficult to identify the genuine article once it has gone through such a transformation and indeed, our colleague’s suspicions were further aroused when the wrong date was given by the buyer of the piece.  Mistakes do happen, it is very difficult to identify coprolite to the genus of animal that produced it in the first place, especially if no provenance is provided with the item.  Often if the gemstone is a coprolite it may have actually have been produced by a crocodile or turtle rather than a dinosaur.  By claiming it is “dino poo”, the price can be bumped up a little.