Life rather than climate influences diversity at scales greater than 40 million years.

The diversity of life on Earth is controlled by hierarchical processes that interact over wide ranges of timescales1. Here, we consider the megaclimate regime2 at scales ≥1 million years (Myr). We focus on determining the domains of 'wandering' stochastic Earth system processes ('Court Jester'3) and stabilizing biotic interactions that induce diversity dependence of fluctuations in macroevolutionary rates ('Red Queen'4). Using state-of-the-art multiscale Haar and cross-Haar fluctuation analyses, we analysed the global genus-level Phanerozoic marine animal Paleobiology Database record of extinction rates (E), origination rates (O) and diversity (D) as well as sea water palaeotemperatures (T). Over the entire observed range from several million years to several hundred million years, we found that the fluctuations of T, E and O showed time-scaling behaviour. The megaclimate was characterized by positive scaling exponents-it is therefore apparently unstable. E and O are also scaling but with negative exponents-stable behaviour that is biotically mediated. For D, there were two regimes with a crossover at critical timescale [Formula: see text] ≈ 40 Myr. For shorter timescales, D exhibited nearly the same positive scaling as the megaclimate palaeotemperatures, whereas for longer timescales it tracks the scaling of macroevolutionary rates. At scales of at least [Formula: see text] there is onset of diversity dependence of E and O, probably enabled by mixing and synchronization (globalization) of the biota by geodispersal ('Geo-Red Queen').