discussion post paleozoic disaster 1

What do you think it was about the Cambrian fauna and the modern fauna (Jack Sepkoski classified them in 1981, consisting of modern marine inveretbrates, such as mollusks and echionderms) that eventually led to the demise of the former and the success of the latter?

In your opinion, how could an Earth event lead to such a widespread disaster for life as that which occurred at the end of the Paleozoic era?

For some insight on the mass extinction, listen to this brief discussion on https://www.pbs.org/wgbh/nova/earth/bowring-extinc…

at least 250 words