Latest Cretaceous Stories
For 300 million years, they were the ultimate survivors. They successfully negotiated three mass extinctions, only to die out eventually at the end of the Cretaceous along with the dinosaurs: Ammonoids, or ammonites as they are also known, were marine cephalopods believed to be related to today's squid and nautiloids. Ammonoids changed their reproductive strategy early on in the course of evolution. However, what was once a successful initial strategy may well have proved to be a fatal...
New research from the American Museum of Natural History shows that America’s Great Plains region may have once been home to some typically sea-bound creatures. Ammonites — a type of shelled mollusk, now extinct and closely related to the nautiluses and squids of today — may have lived in methane seeps when a seaway once covered America’s midwest. The findings have been published online in the journal Geology, and shed some new light on how and where these ancient animals lived....
The dinosaurs of the Cretaceous may have faced an unexpected hazard: fire! In a paper published online today, researchers from Royal Holloway University of London and The Field Museum of Natural History in Chicago have shown that during the Cretaceous (145-65 million years ago) fire was much more widespread than previously thought. The researchers traced fire activity in the fossil record through the occurrence of charcoal deposits, compiling a global database for this time interval....
A 16-member international team of researchers that includes James Kennett, professor of earth science at UC Santa Barbara, has identified a nearly 13,000-year-old layer of thin, dark sediment buried in the floor of Lake Cuitzeo in central Mexico. The sediment layer contains an exotic assemblage of materials, including nanodiamonds, impact spherules, and more, which, according to the researchers, are the result of a cosmic body impacting Earth. These new data are the latest to strongly...
The March GSA TODAY, the Geological Society of America’s open-access science and news magazine, is now online at http://www.geosociety.org/gsatoday/archive/22/3/. This month’s science article, by Todd LaMaskin of the University of North Carolina at Wilmington, presents uranium-lead dating analyses of detrital zircon grains in Paleozoic-Mesozoic basin sediments in the Cordillera of western North America. LaMaskin's analysis shows a systematic variation in age distribution within the...
Researchers at the Institut Català de Paleontologia Miquel Crusafont (ICP), the Museu de la Conca Dellà (MCD) and the Universitat Autònoma de Barcelona (UAB) have published this week in the online edition of the journal Cretaceous Research the discovery and description of a turtle from the end of the age of dinosaurs. Josep Marmi, Angel Lujan, Angel Galobart from ICP, Rodrigo Gaete from MDC, and Violeta and Oms Oriol Riera from UAB have named this new species as Polysternon isonae, in...
A cosmic one-two punch of colossal volcanic eruptions and meteorite strikes likely caused the mass-extinction event at the end of the Cretaceous period that is famous for killing the dinosaurs 65 million years ago, according to two Princeton University reports that reject the prevailing theory that the extinction was caused by a single large meteorite. Princeton-led researchers found that a trail of dead plankton spanning half a million years provides a timeline that links the mass...
Seeking to better understand the level of death and destruction that would result from a large meteorite striking the Earth, Princeton University researchers have developed a new model that can not only more accurately simulate the seismic fallout of such an impact, but also help reveal new information about the surface and interior of planets based on past collisions. Princeton researchers created the first model to take into account Earth's elliptical shape, surface features and ocean...
University of Colorado researchers have found that worms were among the first animals to surface after an asteroid plowed into the Gulf of Mexico 65.5 million years ago. Geological sciences Associate Professor Karen Chin of the university said this "K-T extinction" is often focused on the survival and proliferation of mammals, and studies show some of the earliest terrestrial ecosystems to emerge were aquatic plants. However, new evidence from North Dakota shows networks of...
The same meteorite impact that caused dinosaurs to go extinct 65 million years ago also essentially wiped out ancient birds, a team of paleontologists claim in a new study. The researchers, led by Nicholas Longrich of Yale University, studied collections of approximately two dozen bird fossils of various species from the school's Peabody Museum of Natural History, as well as from the American Museum of Natural History, the University of California Museum of Paleontology, and the...
Latest Cretaceous Reference Libraries
Image Caption: Head of Tenontosaurus, Institut de paléontologie humaine, Paris, France. Credit: Rémih/Wikipedia (CC BY-SA 3.0) Tenontosaurus, meaning “sinew lizard”, is a genus of medium to large sized ornithopod dinosaur. The genus is known from the late Aptian to Albian ages of the middle Cretaceious period sediments of western North America, dating roughly between 115 to 108 million years ago. It was formerly thought to be a ‘hypsilophodont’, but since Hypsilophodontia is no...
Sauroposeidon, meaning “earthquake god lizard,” is a genus of sauropods dinosaur from the Aptian and Albian ages of the Early Cretaceous Period (110 million years ago). It was discovered in the southeast region of Atoka County, Oklahoma, not far from the border of Texas, in a claystone outcrop. The fossils were initially misidentified as pieces of petrified wood when they were found in 1994. A more detailed analysis in 1999 revealed they were truly dinosaurian bones. They were formally...
Qiaowanlong is a genus of sauropod dinosaur from the Albian stage of the Early Cretaceous Period (100 million years ago). It was discovered in the Yujinzi Basin of Gansu, China in 2007. It came from the geological formation called the Xinminpu Group. Qiaowanlong is known from articulated cervical (neck) vertebrae and a right pelvic girdle, as well as several unidentified bone fragments. It was the first brachiosaurid to have been found from China. Qiaowanlong is estimated to have been...
Qantassaurus is a genus of ornithopod dinosaur from the late Aptian to early Albian age of the Early Cretaceous Period (115 million years ago). It lived in Australia when the continent was still south of the Antarctic Circle, and was still part of the supercontinent Gondwana. Qantassaurus was discovered in 1996 during the third annual field season of the Dinosaur Dreaming Project, a dig jointly run by Monash University and Museum Victoria. It was found in the intertidal site known as Flat...
Santanaraptor, meaning "Santana Formation thief", is a genus of theropod dinosaur from the Albian or Aptian stage of the Early Cretaceous Period (108 million years ago). It lived in what is now South America. When first discovered, Santanaraptor was thought to be a maniraptoran theropod. However, it is now thought to be a primitive coelurosaur based on features present on the femur. The type species, S. placidus, was first described by Kellner in 1999. The species name refers to Placido...
