The quaternary extinctions start to occur in Australia around ~60k years ago, South America ~15k years ago, Madagascar ~1k years ago, and New Zealand ~700 years

The quaternary extinctions start to occur in Australia around ~60k years ago, South America ~15k years ago, Madagascar ~1k years ago, and New Zealand ~700 years ago. These numbers are very shortly after when humans first show up in each place. While climate change probably bears some of the blame, massive climate change is actually a regular feature of the last 2.5 million years. As the earth passes through glacial and interglacial phases, the temperature varies by as much as 10°C. The biggest change in the past cycle is us, humans, who now constitute some 36% of mammal biomass. I suggest that extrapolating backwards from the present state, as well as from recent first-colonization events, we should assume that ecological pressure from humans -including predation, displacement, and disruption of habitat and food webs- is the principle factor.