Melksham Monster, predator of Jurassic Britain’s oceans
In 1875, the University of Edinburgh’s Natural History Museum acquired a heavily damaged fossil, unearthed from the English town of Melksham. Nearly 150 years later, scientists have identified it as a new species, a huge marine predator that changes the prevailing view of when the ancient relatives of modern crocodiles evolved. At age 163 million years, the fossil of Ieldraan melkshamensis, or the “Melksham Monster”, becomes the oldest known specimen of the sub-family Geosaurini, previously believed to have originated 152-157 million years ago.
“Given its very poor preservation, working on this specimen was extremely challenging, but with a lot of patience and comparisons with other known species we were able to identify each piece and recognise that we had a new species,” Davide Foffa of the university’s School of GeoSciences told The Indian Express, crediting colleague Mark
Graham for his work preparing the specimen. The 10-foot animal lived in the warm, shallow seas that covered much of what is now Europe. It would have been one of the top predators in the oceans of Jurassic Britain. Powerful jaws and big, serrated teeth allowed it to feed on large prey, including ancient relatives of squids and perhaps other marine reptiles, Foffa said. The study, carried out with Natural History Museum, London, has been published in the Journal of Systematic Palaeontology.
Some 75 million years ago, large dinosaurs supposed to be plant-eaters were munching crustaceans on the sly. Scientists of the University of Colorado Boulder’s Museum of Natural History examined fossilised faeces, called coprolites, in southern Utah and found fragments of rotting wood as well as thick bits and pieces of fossilised shell. Crustacean shells turned up in at least 10 coprolites in three different stratigraphic layers over a distance of about 13 miles, implying that their ingestion was intentional and would have provided protein and calcium sources.
The evidence suggests that the defecators were hadrosaurs, a family of duck-billed herbivores. But would they still qualify as herbivores after the new findings? “Although we agree that the defecators engaged in omnivorous feeding behaviour, it seems more appropriate to describe them as plant-eaters that also ate crustaceans, because there is still much that we don’t know about their feeding habits. It is likely that the dinosaurs were predominantly herbivorous, and we did not want to suggest that we have fossil evidence that these dinosaurs were as omnivorous as living bears or pigs,” associate professor Karen Chin, the museum’s curator of palaeontology, told The Indian Express.
The coprolites had been discovered by a team from the Denver Museum of Nature & Science who invited Chin to their dig. The study has been published in Scientific Reports. In the Lameta Formation of sedimentary rock in India, too, there are coprolites that contain both plant tissues and tiny crustaceans, Chin said. “However, in this case, the crustaceans are so small that they were probably not intentionally eaten,” she said.
The last supper
Nearly 200 million years ago, a young marine reptile ate a prehistoric squid for its last meal. The specimen, identified by UK scientists, is the smallest (70 cm) and youngest recorded Ichthyosaurus communis, a species first described in 1821. Preserved between the ribs, the fossil had tiny hook-like structures — from the arms of squid. The study has been published in Historical Biology.
Lead author Dean Lomax, a University of Manchester palaeontologist, has led several studies on ichthyosaurs. Last year, he and US scientist Judy Massare identified two new species. Earlier this year, he was in a team of UK and German scientists who discovered the largest ichthyosaur on record. Pregnant at the time of death, it belonged to one of the two new species, Ichthyosaurus somersetensis.
“Yes, it was very interesting studying the smallest and largest,” Lomax told The Indian Express. “Mostly, because you can see some substantial differences (e.g. teeth and size). However, most interestingly, the bones that make up the skeletons are very similar, even from juveniles to adults, which shows that they do not change (that much) as they grow.”
Massive migrating marsupial
A giant prehistoric Ice Age marsupial followed an annual migration in Australia, says a study in Proceedings of the Royal Society of London B. The 3-tonne Diprotodon optatium, up to 1.8 m tall and 3.5 m long, was first described as early as in 1838, University of Queensland palaeontologist Gilbert Price told The Indian Express. The new finding, from a study of its teeth, makes it the only known marsupial to have followed a migration pattern. Diprotodon’s front incisors never stopped growing, Price writes in The Conversation, and the sampling from these revealed seasonal changes in food and water intake as also the various geological provinces where the individual travelled.
Rat that ‘bites open’ coconuts
In 2010, mammalogist Tyrone Lavery of Chicago’s Field Museum, visiting the Solomon Islands, heard rumours of a giant tree-dwelling rat that cracked open coconuts with its teeth. After years of searching, Lavery and his teammates finally found it. “I learned about this rat in January 2010 and we finally captured one at the end of 2015. I made approximately 10 visits to Vangunu Island to look for it,” Lavery told The Indian Express.
The Uromys vika, whose discovery has been published in the Journal of Mammalogy, measures about 50 cm from the nose to the tip of the tail. And while it hasn’t yet been observed cracking open coconuts, it does have a penchant for chewing holes into nuts to get at the meat, the Field Museum said in a statement.
The rat was found scurrying out of a felled tree. It died later. “As soon as I examined the specimen, I knew it was something different,” Lavery said. “There are only eight known species of native rat from the Solomon Islands, and looking at the features on its skull, I could rule out a bunch of species right away.” After comparing the specimen to similar species and checking its DNA against that of its relatives, Lavery confirmed that the giant rat was a new species.