Latest news with #Cenomanian
Yahoo
03-05-2025
- Science
- Yahoo
94 million years ago sea monsters got wiped out by boiling oceans, high CO2: Study
For millions of years, the Late Jurassic and Early Cretaceous oceans belonged to enormous and scary hunters. Among them were pliosaurs with giant jaws, toothy crocodile-like reptiles (thalattosuchia), and sleek, fast, fish-shaped predators (ichthyosaurians, or sea monsters) that dominated the seas. These were apex predators, ruling their underwater kingdoms with unchallenged power. But then, something shifted. The middle Cretaceous saw a dramatic upheaval in the marine world. The long reign of ichthyosaurs, thalattosuchians, and pliosaurids started to end abruptly. They vanished from the fossil record. In their place, a new cast of characters emerged: the mosasaurs, plesiosaurs, and even diverse kinds of sharks. The abrupt disappearance of these long-reigning marine animals and the rise of new ones has long been a mystery for experts. A new study, presented at the General Assembly of the European Geosciences Union next week, sheds light on this ancient mystery. According to Valentin Fischer of the Université de Liège and his colleagues, the culprit was likely a period of intense ocean anoxia and dramatic climate volatility. Ocean anoxia is when large parts lose most or all of their oxygen. This tumultuous era coincided with the Cenomanian/Turonian transition, which estimates suggest occurred around 93.9 million years ago. This was a relatively short but significant period of environmental stress. It is 'the hottest interval of the last 541 million years.' During this transition, carbon dioxide levels soared to their highest point in the Cretaceous. The delicate balance of ocean nutrients, like sulfur and iron, was thrown into disarray. The combination of extreme heat, widespread oxygen loss in the oceans, high CO2 levels, and nutrient imbalances created a challenging environment that likely triggered the die-off of marine life and reshaped marine ecosystems. The study suggests it triggered a major reshuffling of the oceanic food web, leading to the disappearance of established predators and the rise of new ones. 'This transition is associated with a shift in top predators, creating the unique and somewhat short-lived oceanic food webs of the Late Cretaceous,' the researchers noted. The research involved a comprehensive analysis of hundreds of marine reptile lineages. The team examined the evolutionary relationships and compiled the largest 2D and 3D marine reptile data dataset. Through this extensive analysis, they pinpointed how these extinctions unfolded and impacted the predatory capabilities of Cretaceous marine reptiles. 'Our analyses showed that the Cenomanian-Turonian transition is associated with elevated rates of extinction and that these extinctions disproportionally targeted some groups of large and fast predators, in a stepwise manner,' Fischer noted in the press release. Dr. Fischer highlights a key piece of evidence for the shift in predatory capabilities: the significant differences in skull shapes of marine reptiles before and after the Cenomanian/Turonian transition. These altered skull morphologies directly impacted their ability to hunt and consume prey. It led to 'distinct bite force.' The reign of the ancient marine giants ended not with a bang, but with a shift. This dramatic environmental upheaval paved the way for the iconic marine predators of the Late Cretaceous. However, the asteroid event led to the extinction of most of these marine creatures, including mosasaurs and plesiosaurs, approximately 66 million years ago. This new research provides insight into how Earth's forces can cause major evolutionary shifts.
Jordan News
30-04-2025
- Jordan News
Head of Petra Region Commission Explores "Dinosaur Trail" in Al-Saffaha - Jordan News
The Petra Region Authority continues to explore and develop unique tourist trails aimed at diversifying tourism products and enhancing adventure tourism. One of these trails passes through an archaeological site from the dinosaur era, making it a distinctive location with preserved dinosaur footprints embedded within the Naur Formation rocks from the Upper Cretaceous (Cenomanian) period, dating back 94 to 100 million years, according to an international research team from Jordan and Poland, led by Hendrik Klein and Gerard Gierliński, with the participation of Jordanian researchers, including Dr. Abdullah Abu Hamad, Habes Al-Mashaqqa, and Ikhlas Al-Hayyari. اضافة اعلان This marks the first scientific documentation of dinosaur trails in Jordan. Dr. Fares Al-Brezat, Chairman of the Petra Region Authority, confirmed that this trail will provide a unique and valuable addition to the tourism product in the "Golden Triangle," which includes Petra, Wadi Rum, and Aqaba. This will enhance Jordan's position as a key adventure tourism destination on both regional and global levels, and support efforts to extend the length of visitors' stays in the area. The trail also targets new groups of local tourists, particularly younger people interested in dinosaurs. Al-Brezat noted that once completed, this new trail will offer an unparalleled exploratory experience for visitors to Petra, while also contributing to the empowerment of local communities by providing new economic and development opportunities, in line with the Authority's strategy to promote sustainable development in the Petra District and its surroundings. It is noteworthy that the discovered dinosaur footprints in the area are among the rarest finds in the Middle East. They are spread across ancient marine rock layers and feature tracks from three main groups of dinosaurs: theropods, sauropods, and ornithopods, giving the site both scientific and tourist significance. Al-Brezat had previously conducted a field visit to the Al-Saffaha and Ras Al-Fayd areas in Al-Heisha, located in the northwestern boundaries of the region, accompanied by Infrastructure Commissioner Engineer Mohammad Al-Habhabah, along with several relevant department heads from the Authority, as well as Moayad Abu Rumman, Director of the Jordanian Heritage Revival Company, and Mohammad Asfour, President of the Wadi Association for Sustainable Ecosystem Development.
