Cretaceous

number of species within a relatively short period of geological time, thought to be due to factors such as a catastrophic global event or widespread environmental change that occurs too rapidly for most species to adapt." - dictionary.com (1). The Cretaceous-Paleogene (K-Pg) extinction event occurred 66 million years ago. This event meant the extinction of 75% of the Earth's organisms, including the non-avian dinosaurs (2). Many scientists believe that it is the result of the Chicxulub impact…

Elizabeth Kolbert’s book, The Sixth Extinction, covers the argument that we are currently in another mass extinction because the Earth is following similar trends as it did in the past five mass extinctions. The first chapter of The Sixth Extinction starts out by discussing frogs. Frogs are the one of the oldest species on Earth; however, the extinction rates of frogs is higher than it’s ever been, and it’s only increasing. Kolbert then focused specifically on Panamanian golden frogs. Not too…

Number 1:The Ordovician Silurian extinction This extinction happened about 439 million years ago because of a drop in sea levels as glaciers formed. An ice age has been blamed for the cause of the extinctions. A large ice sheet in the southern hemisphere caused climate change and a decrease in sea levels. A combination of this lowering of sea level caused a reduction in ecospace on continental shelves, and the cooling caused by the glaciation itself are some of the big factors for the…

also makes use of specific word choices to improve her argument. She often uses highly academic phrasing to appear more educated in her subject or argument, thus lending credibility to her argument. “Amenity to envy”, “Profligate water” use, and “Cretaceous age rock” (Barnett, 338) are all examples that occur in the first two paragraphs. She also makes use of more emotional wording. Such as “imperil future generations” (Barnett, 340), and to sway her readers to her…

Bahariya Formation in Egypt to the Kem Kem Formation in Morocco. The ages that this creature roamed the earth in are known by most geologists as the Albian Age (112-100 mya) and the Cenomanian Age (100-95 million years ago), which are inside of the Cretaceous Period (149-65 million years ago). Back then the climate of northern Africa was very different from what it is today. The climate was still just as warm as it now, maybe warmer, but it was much more humid. Where there are deserts and…

oxygen concentration, which would suffocate those who would breathe oxygen, and promote the growth of anaerobic bacterias. The poisonous gas from these anaerobic bacterias would have killed off the rest of the animals and plants. The cause of the Cretaceous mass extinction is believed to have been the collision of a large comet or asteroid with Earth. The impact from this comet or asteroid would have resulted in a cloud of debris that would have blocked off sunlight and severely disturbed the…

the planet earth to transform radically. This event is known as the Permian Triassic Mass Extinction or also called by many the Great Dying. This mass extinction is known as the worst extinction comparing them to the Ordovician, Devonian and the Cretaceous Extinction. Some individuals are not award that the Permian –Triassic are two forming boundary between the end of the Permian and the beginning of the Triassic period. The Permian-Triassic Extinction almost killed the whole Earth. Since this…

Did one single disaster cause the K-T extinctions? Some scientists and people are committed to just one reason the K-T extinctions occurred but in this paper many possibilities will be explored with evidence to back up why they could have been a cause as well to the extinctions. Everyone will ultimately make his or her own decision/thoughts on what could have happened, and of course all hypotheses would be subject to analysis. Asteroid impact theory. The impact of a 10 km+ asteroid would blow a…

birds. The elongated arm bones that support the wing evolved in the first coelurosaur. An Apatosaurus and tyrannosaurus rex are extremely different from each other. An Apatosaurus lived in the Late Jurassic, while a tyrannosaurus lived in the Late Cretaceous. An Apatosaurus was an Herbivorous; while a tyrannosaurus was a carnivorous. An Apatosaurus was also almost twice of a Tyrannosaurus’ size. 4. The Ornithischian dinosaur, or "bird-hipped" dinosaurs, and the Saurischian dinosaur, or…

enclaved region formed by the post Antler tectonism including: Late Paleozoic deformation, uplift and removal of some parts of the Roberts mountain allochthon; emplacement of the Golconda allochthon over Roberts Mountain allochthon; Jurassic and Cretaceous of the Cordilleran fold and thrust belt; and Cenozoic Basin and Range Tectonism. Speed and Sleep (1982) focused on the enclaved region to support the Arc-collision hypothesis, and they believed that within this enclaved region (1) Antler…