Giving {brainliest} and {50 points} 1. how are scientist able to tell that mass extinction took place during devonian time period 2. what do scientist expects caused mass extintion. (disclamer): if answer is not clear not right nor thought out you will het {reported}

To determine that mass extinction took place in Devonian time the paleontologist would have to study the fossil content of the lower Devonian and then in later Devonian to see how the  amount of species diminished drastically.Some of the theories put forward for this include imThese include impacts by asteroids ,global oxygen shortages, plate tectonics and the distribution of continents, climate change and sea level changes.