What led to the extinction of dinosaurs?
Here are five theories: Probably the most popular theory right now is the Asteroid Theory. According to this theory a large asteroid or comet collided with Earth about 65 million years ago. Scientists think that such a large collision would throw so much dust into the air that sunlight would not be able to shine and plants and animals would die. The dramatic changes in climate that resulted from this huge collision were too much for the dinosaurs. They were not able to survive. Another theory that could explain how the dinosaurs became extinct is volcanic activity. A huge increase in volcanic activity at around 65 millions years ago could have pumped so much ash into the air that it blocked out the sun killing the dinosaurs. Some scientists believe that there was a severe ice age. Throughout Earth’s history there have been many ice ages. The last one ended about 10,000 years ago. A very severe ice age could have changed temperatures and frozen a lot of Earth’s water. The dinosaurs woul
The size of the dinosaurs, and most prehistoric animals from then were all bigger than anything today, including insects, at the exception of aquatic life. Science shows that things like lizards and insects cannot be this sisely and live in today’s environments, because the gravitational pull would crush them. Whereas, the gravity level must have been different back then, if they could survive. So, I think something hit the Earth really bad and knocked it off its axis, unto the one that it finds itself on now. I wonder though, if it was knocked within or without its axis. I can’t just base “without” on the fact that it was always hot and humid, therefore logically closer to the sun…because the Earth was young then, and a lot of volcanoes were active. Still, I think this is what killed dinosaurs, and ushered in an ice age due to disrupting the weather so abruptly, which served to wipe everything else out. After adaptation, life started again, but there’s where it makes no sense to me
The most widely accepted theory is that a meteorite/asteroid plummeted through the atmosphere and caused such a large explosion (which rivals that of a nuclear explosion) that the shock wave was too toxic/hot that it killed pretty much all living creatures on the planet. The dinosaurs had evolved so well for their environment that the huge change caused too much variance for them to survive. Only those that were slightly evolved but not entirely (mammals for example) could handle with the variance.
Depends who you ask. A popular theory is the asteroid collision but there are big problems with this one. Few dispute an impact (or even a couple) occured but the impact (excuse the pun) of this is very uncertain. There are issues like the famous “frog problem”. Another theory is the Deccan traps eruptions causing profound long term climate change. And not all dinosaurs (or other creatures) died out. Some became birds. It was probably a combination of factors. The impact(s) may have been one factor but doesn’t explain everything.
“There have been several theories on the cause of the K-T boundary which led to the massive extinction. These theories have centered on either impact events or increased volcanism; some include elements of both. A scenario combining three major postulated causes: volcanism, marine regression, and extraterrestrial impact has been proposed. In this scenario, terrestrial and marine communities were stressed by the changes in and loss of habitats. Dinosaurs, as the largest vertebrates, were the first to be affected by environmental changes, and their diversity declined. At the same time, particulate materials from volcanism cooled and dried areas of the globe. Then, an impact event occurred, causing collapses in photosynthesis-based food chains, both in the already-stressed terrestrial food chains and in the marine food chains.
