How are the extinctions now different from most extinctions in the past?

Because we are advancing and using more energy andm aking more citys

The fastest extinction of life on Earth occurred 65 million years ago when over 80% of the earth's organisms went extinct. This occurred in a relatively short 2-5 million years,

fossils

Mass extinction- More than 50% of the population went extinct in a short period of time. Background extinction- An average rate of extinction for a given time period.

Extinction is the complete disappearance of a species from life. No more of that species is alive on the planet. It happens all the time; the normal rate of extinctions is called the background...