The first one was of the dinosaurs. I think it was the cretaceous period, but not sure. the widely accepted cause was a giant meteor that crashed into the Gulf of Mexico, causing a dramatic climate change that the dinosaurs could not adapt to. The second one was of the 'magafauna', or large animals, of the North American ( and I think of the South American ) continent. The animals included the wooly mammoth, giant sloth, saber-tooth tiger, etc. This happened about 15,000 years ago. In a science program currently running on TV, it is shown that scientists have found startling new evidence that this extinction was ALSO caused by a meteor - most likely several small meteors - crashing into earth.
For all mass extinctions (except the Cretaceous/Paleogene extinction) two probable causes are volcanic eruptions and ocean anoxia.
An asteroid from space, and Gradualevents
ice age,Noahs flood in bible
explanation about atomic mass of bromineIsotope Atomic mass Abundance(%) 79Br 78.91834 50.6981Br 80.91629 49.31therefore:Atomic mass of bromine element = 78.91834x0.5069+80.91629x0.4931= 79.904
human activities appear to have eliminated two or three species per decade, about double the naturalextinction rate.
For all mass extinctions (except the Cretaceous/Paleogene extinction) two probable causes are volcanic eruptions and ocean anoxia.
An asteroid from space, and Gradualevents
Most extinctions occur as background extinctions because they are longer time periods unlike the shorter mass extinctions which there were only two in the Paleozoic era, the Ordovician mass extinction, and the Permian/Triassic extinction in which 95% of all marine animals became extinct
ice age,Noahs flood in bible
Two probable causes of mass extinctions are volcanic activity and asteroid impacts. Massive volcanic eruptions can release large amounts of ash and gases, leading to climate changes and disrupting ecosystems. Similarly, asteroid impacts can cause immediate destruction and trigger long-term environmental shifts, such as blocking sunlight and altering temperatures, resulting in the collapse of food chains. Both phenomena have been linked to significant biodiversity loss in Earth's history.
Matter has mass and occupies space. So, mass and volume are the two major properties of matter.
Mass extinctions--at least two--one at the end of the Permian, and one at the end of the Cretaceous, with numerous other less severe events. As far as the extinction of individual species, that list would cover millions of extinct organisms.
Two major eras that ended with mass extinctions are the Permian-Triassic extinction event, which marked the end of the Permian period, and the Cretaceous-Paleogene extinction event, which marked the end of the Cretaceous period. These events had profound impacts on life on Earth, leading to the loss of a significant number of species.
mass and acceleraiton
Two significant periods of mass extinction on Earth include the Permian-Triassic extinction, approximately 252 million years ago, which wiped out about 90% of marine species and 70% of terrestrial vertebrates. Another major event is the Cretaceous-Paleogene extinction, around 66 million years ago, famously associated with the asteroid impact that led to the demise of the dinosaurs and about 75% of species on Earth.
What are two natural factors that caused an extinctions
The two major causes were the Homestead Act and the completion of the Transcontinental Railroad.