Cretaceous-Rat Extinction Research Paper

“A minority disputes this theory, arguing that other events-such as volcanic eruptions, sea-level changes or a series of impacts-were to blame for the spectacular loss of species that occurred at the transition between the Cretaceous and Tertiary periods…”

Was it the confluence of events outlined in this review (including the prevailing global climate, volcanism), or are some of these factors secondary? For example, we have little idea of the mass of methane hydrates in the Late Permian ocean floor. These and many other questions will need to be addressed before we fully resolve the cause of the end-Permian mass extinction. However, there is a growing realisation that flood basalt volcanism has the potential to be the primary trigger for mass extinctions, rather than meteorite impacts or other external

The End Cretaceous impact hypothesis states that an asteroid impact on the earth caused the extinction. The evidence that supports this hypothesis include the crater found in the Yucatan Peninsula, the rare metal Iridium, and fractured “shocked quartz” crystals that have been shown to cause high-energy explosions. The End Cretaceous flood volcanism hypothesis states that a giant volcano eruption, or a series of volcano eruptions caused the extinction The evidence that supports this hypothesis includes immense lava flow, and volcano explosions, which happen to exposed iridium.

The most well-known extinction event is when the dinosaurs went extinct, although they are not the only organism that perished. This event took place about 65 million years ago, between the Cretaceous and Tertiary periods and wiped out nearly 75% of plants and animals (Principles of Biology). Our book says that most dinosaurs and many other sauropsid lineages died, but many lineages survived, including bird. Crocodiles are lineage of dinosaurs and are often studied to see how they have changed over millions of years, turtles are also part of the lineage that survived. Asteroid impact hypothesis which can be found in class rooms, some textbooks and on TV or in movies has been well explained and accepted as the cause of the extinction of dinosaurs. There is geological evidence that supports a large asteroid creating the Chicxulub crater on the Yucatan Peninsula of Mexico, but the supposed consequences of the event alone cannot account for the major extinctions (Principles of Biology). They say that something else had to also happen in order for all the diversity of animals that became extinct, which would be expected when such a large object impacted earth at what is thought to have been at a high speed too. Changes in sea level and massive volcanic eruptions were also altering the environment, so all this combined is likely what cause the diversity in the extinction event (Principles of

The Cretaceous mass extinction is the most well-known case of meteorite impact on the earth, but it certainly is not the only one. It is merely the most well-known. Due to the impact, debris entered earth's atmosphere and caused the plant life of the time to die off due to the lack of sunlight to survive. This made food much more scarce for the species that were dominant at the time. The competition was simply too much for them, and as the plant life died out, so did the herbivores and then the carnivores died out as well. Not only the land was impacted, however, the sea life was affected heavily by this impact as well. The lack of sunlight caused the oceans to become colder, causing the habitats of many marine animals to be drastically altered

The Cretaceous-Tertiary extinction or K-T extinction, which marks the Late Cretaceous, is a massive and large-scale extinction of animal and plant species that occurred over a short period of time 66 million years ago.

Secondly there is the Volcanism theory of dinosaur extinction which is to do with volcanic activity wiping out the dinosaurs. The end of the Triassic period is when these super continents had separated from each other, during early Cretaceous period Gondwanaland had begun to break apart. When continents move the continental plates move as well slowly, whilst moving they can collide, slide under or over other plates. The plate boundaries are generally sites of geological activity. Pressure can build up causing a break at weak points called faults. These faults may cause volcanic eruptions of earth quakes. The theory is so much volcanic activity and earthquakes were occurring toxic volcanic gas began to settle on the Earth's surface poisoning the dinosaurs as well as earthquakes killing them

Mass extinction of the Dinosaurs the most dramatic extinction in the history of the Earth. ( national geographic, 2015 ) The dinosaur extinction could have been sudden or gradual depending on the cause. Scientists have thoroughly researched and finally found two major options, the asteroid impact theory and the volcanic theory, that have many similar qualities, but on the other hand are very different. These two theories could have possibly caused the extinction many years ago.

The Cretaceous-Paleogene boundary (K-Pg boundary) was host to one of the three largest mass extinctions in the past 500 million years. Evidence suggests it was the result of a large asteroid impact approximately 65.5 million years ago in Chicxulub, Mexico; hence why the crater it formed was named the Chicxulub crater. The crater was approximately 180 kilometres in diameter and was believed to have led to the extinction of the dinosaurs amongst many other life forms including marine plankton (calcareous nannofossils and planktonic foraminifera) (Schulte et al., 2010). Furthermore, it had a number of impacts on the atmosphere and environment including the creation of sulfuric acid rain and stratospheric dust cloud formations.

The K-Pg event, the day life on earth was wiped out, is one of the most notorious extinctions in the history of the world. From jawed fish, to plants, to crocodyliforms (10 species’ fossils have been found, 5 of which are extinct), even a species of pterosaurs, life was extinguished; however, what happened to the creatures? What truly killed the dinosaurs? There are many theories but some ideas are downright insane. Some older ideas consist of comets dusting the Earth with a poisonous gas, or the caterpillars eating the plants, starving the herbivores; then the carnivores because they had nothing to eat but each other. Another theory is that the continental shift built up mountains, and over time those mountains changed the climate and the

Everyone knows about the dinosaurs and how they went extinct. This was one of the major events that took place in the Cretaceous Time Period. The Cretaceous Period was the longest and last of three time periods in the Mesozoic Era. This time period lasted from about 144 million years ago until about million years ago (about 79 million years), and over that 79 million years the earth changed dramatically.

Ever since the history of Earth has been studied using fossil records, extinctions have always been the object of fascination and interest, particularly the mass extinctions that occurred throughout Earth's history. A mass extinction can be caused by disruptive global environmental changes, where large numbers of species have become extinct (Urry et al. 2008). There have been five major extinctions documented based on fossil records over the past 500 million years, but the Cretaceous (KT boundary extinction – a name that meant it began the Tertiary era) extinction caught a lot of

As young kids, we spent no shortage of time learning about all of the animals that have inhabited planet earth since the origin of time. And while there are tons and tons of fascinating species in the world, there was always one topic in particular that stood out to all of us- dinosaurs. Whether it was just the sheer concept of another species living on the earth before we were even alive, or the tales we were told about their incredible strength and size, we were transfixed by dinosaurs, specifically their disappearance. One thing that never quite made sense was how such an exceedingly powerful group of animals, that lived in what seemed to be every corner of the world at one point, could just up and vanish one day. The answer of

Over 98% of all organisms that have lived on Earth are now extinct. A mass extinction event occurs when a large number of species die out within a small time frame (relative to the age of Earth). Mass extinctions are intensively studied for both cause and effect, as there is usually room for debate regarding catalysts that precede the extinction and the massive influx of new biological species that follows. There have been five major mass extinctions, dubbed the “Big Five,” that have wiped out at least 50% of the species living at those times. The most well known mass extinction of the Big Five, with the decimation of every species of non-avian dinosaur, is the Cretaceous-Paleogene

Nobody can really say what actually eliminated the species, although everyone has their very own idea. Asteroid impact, atmospheric changes (hot to cold), catastrophic eruptions and astronomical events (supernovas etc.). Some have ventured that early mammal inhabitation slowly “pushed” the dinosaurs to extinction. The most favored theory in the scientific field is that of the meteor impact. As always though, knowing when is part of discovering how and why.