Various answers. I like about 16,000 years ago in North America. Probably a meteor strike, so it lasted between minutes and weeks. Killed all the big animals, including humans (the Clovis point people).
The most devastating mass extinction occurred in the Late Permian (~250 million years ago).
Mass Extinction
540 million years ago was the first mass extinction
The death of many species in a short amount of time is known as a mass extinction event. These events can be caused by a variety of factors such as natural disasters, climate change, or human activities. Mass extinctions have occurred several times throughout Earth's history.
The Permian mass extinction occurred about 248 million years ago and was the greatest mass extinction ever recorded in earth history exterminating more than 95% of all life on EarthTwo theories have been proposed - the impact of a huge meteorite or comet over 10 kilometres in diameter, or a massive and prolonged volcanic eruption. The volcanic theory appears to be taking the lead at the present time.
asteroid attack
Which mass extinction? There have been five such events. The first one, the Ordovician-Silurian extinction event occurred before the Devonian. The Late Devonian event occurred during the Devonian. All other mass extinctions occurred after the Devonian.
The Cretaceous–Tertiary extinction event 65 million years ago was the last mass-extinction, and many believe that humans are causing a mass-extinction right now.
The most devastating mass extinction occurred in the Late Permian (~250 million years ago).
No, child, I was not a witness to the Permian Extinction. The Permian extinction event is the only known mass extinction of insects. The Permian extinction event occurred about 252 million years ago.
Notable extinctions during the last mass extinction included all non-avian dinosaurs, pterosaurs, plesiosaurs, and ammonites.
Mass Extinction
Mass Extinction
Mass Extinction
Mass Extinction
If the Cretaceous mass extinction had not occurred, reptiles would today be the largest land animal in the world. At the time, reptiles were the largest animal group on Earth.
That is usually referred to as a Mass Extinction, and what has happened is some very major event has occurred that cuts off the animals' ability to either eat, produce offspring, or otherwise survive, without a chance of migration to better locations.