Question

1. what occurs during a mass extinction?

Explanation:

A mass extinction is an event in which a large number of species go extinct within a relatively short geological time period. This can be caused by various factors such as large - scale volcanic eruptions, asteroid impacts, climate change (like rapid cooling or warming), and oceanic anoxia (lack of oxygen in the ocean). During a mass extinction, ecosystems collapse as many species that play crucial roles (e.g., keystone species) are lost. This leads to a major reshuffling of life on Earth, with some groups of organisms disappearing completely and others having the opportunity to diversify in the post - extinction environment.

Answer:

During a mass extinction, a large proportion of Earth's species become extinct within a relatively short geological time frame. This often disrupts ecosystems, causes the collapse of food webs, and can lead to the end of dominant groups of organisms, allowing for the subsequent diversification of surviving species.