China News Service, Beijing, November 10 (Reporter Sun Zifa) The reporter learned from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences that Dr. Li Lu and his collaborators have collected data from the stratum about 20 million years ago in Sunite Zuoqi, Inner Mongolia. After in-depth study of the fossils of Hedgehog, a new genus of the Hedgehog subfamily was recently discovered, named "Wendusunite Hedgehog". Its skull and jaw features are classified into the Hedgehog subfamily, but its teeth are particularly special.
The type specimen of Wendusunite Hedgehog is a skull with an occipital defect and associated mandible. It is the most complete Neogene (about 23 million to 26,000 years ago) fossil material of the Hedgehog subfamily known in China.
Its genus name comes from Sunite Zuoqi, the place where the fossils originated, and the species name is dedicated to Wen Dusu, the former director of Sunite Museum. The related research results were recently published in the international professional academic journal Historical Biology.
Dr. Li Lu, the first author and corresponding author of the paper, said in an interview with a reporter from China News Agency that hedgehogs are typical omnivorous opportunists, and their diet includes insects, other invertebrates such as worms, terrestrial mollusks and spiders , and even small vertebrates and eggs.
In addition, they also eat plant fruits, seeds, tubers and mushrooms.
Among them, the Hedgehog subfamily prefers to prey on small invertebrates; the extinct short-faced Hedgehog subfamily may be more inclined to prey on small vertebrates, which have developed cleft teeth; members of the Hedgehog subfamily are open to all, and their The teeth are like Swiss Army knives with multiple functions such as cutting and crushing. It is the polyphagy and the other two characteristics-the appearance of spines and hibernation, which makes the Hedgehog subfamily the most common among the Hedgehog family and even the entire insectivore. However, the researchers' latest fossil study shows that there are exceptions in the evolution of members of the subfamily Hedgehog.
A comparison of the upper and lower premolars between Wendusu Sunite and Taqin Gol's close species.
Photo courtesy of the Institute of Ancient Spine, Chinese Academy of Sciences
Li Lu pointed out that the Undussunite hedgehog is one such exception - its skull and jaw features unquestionably place it in the subfamily Hedgehog, but its dental features are quite different from all other members of the subfamily: The cusps of the premolars and molars of the new genus are rounded and blunt, and the ridges are underdeveloped. In particular, the enlarged fourth lower premolars have a strong lower protomolar, the lower anterior cusp is degenerated, and the lower posterior cusp and the lower anterior ridge are missing.
These teeth usually have strong crushing ability and weak cutting ability, that is, Undussunite hedgehogs are shell-eating (that is, eating food with hard shells), and shell-eating is not common in insectivorous species. Uncommon, previously known only to certain fossil genera species in the family Diplodocidae and Shrellidae.
In this study, it is believed that the fossil genus Proterix and Galerix uenayae, which have similar tooth characteristics, also have similar food habits, and it is the first time to propose that the Hedgehog family and the Hedgehog subfamily Has shell food.
He said that the diversity of Hedgehogs is very high in the fossil sites of the new genus. In addition to the new genus Vendususunite Hedgehog, there are also one or two species of Double Hedgehog and two members of the Short-faced Hedgehog subfamily. .
Undussunite hedgehogs likely ate coleopteran insects or terrestrial gastropods common at fossil sites to avoid direct competition with other members of the Hedgehog family in their limited living space.
At the same time, this latest study believes that not only some morphological characteristics of Sunite hedgehogs are close to members of the subfamily Scytheidae, but also the morphological characteristics of Scymnerix tartareus, a member of the subfamily Scymnerix tartareus in the Late Oligocene of Mongolia, in some aspects. Close to members of the short-faced Hedgehog subfamily.
During the period from the Late Oligocene (about 28 million years ago) to the Early Miocene (about 16 million years ago), "it is the extraordinary morphological plasticity and strong environmental adaptability of the subfamily Hedgehog that makes it a The competition between the Hedgehog subfamily and the Short-faced Hedgehog subfamily gradually gained an advantage. In the end, the Hedgehog subfamily was on the sidelines, the Short-faced Hedgehog subfamily all went extinct, and the Hedgehog subfamily flourished to this day." Li Lu said.
(Finish)