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
