Not just one factor. Climate change is one part of the whole when it comes to biosphere collapse. Massive use of persistent pesticides have disrupted the beneficial insect life on the planet - not just the bees. Microplastics in combination with warming and increasingly deoxygenated seas in combination with massive overfishing are killing ocean life. The percentage of wildlife on the planet is the lowest it's ever been since hominids first showed up, and we just keep making more of ourselves.