However, when and where these highly specialized marine reptiles originated remained unclear until now. A 246-million-year-old skull of a juvenile placodont was recently discovered in the Netherlands. Paleontologists from the universities of Zurich and Bonn have now proved that it is one of the earliest examples of this saurians and that it originated in Europe.
Reconstruction of the juvenile placodont Palatodonta bleekeri. The teeth are striking compared to other placodonts. Picture: reconstruction by Jaime Chirinos
The recently discovered skull of a juvenile placodont from Winterswijk, the Netherlands. Picture: UZH
For around 50 million years, placodonts populated the flat coastal regions of the Tethys Ocean, in modern day Europe and China. The most distinctive feature of these dinosaurs was their teeth: The upper jaw had two rows of flattened teeth – one on the palate and one on the jawbone – while the lower jaw only had one set of teeth ideal for crushing shellfish and crustaceans.
The evolutionary origins of these placodonts remained unclear. However, a new find in a 246-million-year-old sediment layer now sheds light on the origin and phylogenetic development of the placodonts. As the Swiss and German team headed by Torsten Scheyer, a paleontologist at the University of Zurich, reveals the skull found in Winterswijk (Netherlands) is the earliest form of all known placodonts. The juvenile animal lived 246 million years ago. At around two centimeters in size, the skull is exceptionally well preserved and its characteristics set it apart from previous placodont discoveries.
Double row of pointed teeth
The basal-most known placodonts to date have the group’s trademark double row of crushing teeth in the upper jaw. The flattened teeth that give these animals their name only appear in more derived placodonts. “Unlike all the other placodonts discovered to date, the Winterswijk specimen has conical, pointed teeth instead of flattened or ball-shaped crushing ones,” explains Scheyer, “which means the pointed teeth on the lower jaw slotted precisely into the gap between the palate and upper-jawbone teeth when biting.”
The group’s trademark double row of teeth in the upper jaw is proof that the new find is actually a placodont. According to the researchers, the teeth of Palatodonta bleekeri, the scientific name given to the Winterswijk specimen, were specialized in gripping and piercing soft prey. “The double row of teeth in the new find combined with its considerable age lead us to conclude that it is a very early placodont, from which the later forms developed,” says Scheyer. The formation of crushing teeth and the specialization of a diet of shellfish and crustaceans thus developed later within placodont evolution.
European origin confirmed
The small Palatodonta bleekeri skull sheds new light on the ongoing debate on where the placodonts originated: Previous finds suggested origins in the shelf sea areas of either present-day China or Europe. Due to the considerable age of the new Dutch find and its basal form, however, the European origin of the placodonts is deemed confirmed. Scheyer and his colleagues are hoping for further exciting finds in Winterswijk to discover more about the evolution of the placodonts.Literature:
Nathalie Huber | Universität Zürich
Novel method for investigating pore geometry in rocks
17.06.2018 | Kyushu University, I2CNER
Decades of satellite monitoring reveal Antarctic ice loss
14.06.2018 | University of Maryland
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...
Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.
From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
15.06.2018 | Materials Sciences
15.06.2018 | Ecology, The Environment and Conservation
15.06.2018 | Power and Electrical Engineering