write about :
Overview of the causes of megafauna extinctions
Human activities as the dominant cause of megafauna extinctions.
Cascading effects of megafauna extinctions on ecosystems and human societies
Megafauna extinctions as an indication of the profound impact of human activities on ecosystems.
Keystone role of megafauna in ecosystems and their extinction as a significant loss to biodiversity.
Implications of megafauna extinctions for current and future conservation efforts