Oh for fuck's sake, just read the paper: BOX 1: Past planetary-scale critical transitions and state shifts Last glacial–interglacial transition18,24. The

Oh for fuck's sake, just read the paper: BOX 1: Past planetary-scale critical transitions and state shifts Last glacial–interglacial transition18,24. The critical transition was a rapid warm–cold–warm fluctuation in climate between 14,300 and 11,000 yr ago, and the most pronounced biotic changes occurred between 12,900 and 11,300 yr ago24,27,30,54. The major biotic changes were the extinction of about half of the species of large-bodied mammals, several species of large birds and reptiles, and a few species of small animals30; a significant decrease in local and regional biodiversity as geographic ranges shifted individualistically, which also resulted in novel species assemblages37,49,53,54; and a global increase in human biomass and spread of humans to all continents27. The pre-transition global state was a glacial stage that lasted about 100,000 yr and the post-transition global state is an interglacial that Earth has been in for approximately 11,000 yr. The global forcings were orbitally induced, cyclic variations in solar insolation that caused rapid global warming. Direct and indirect of effects of humans probably contributed to extinctions of megafauna and subsequent ecological restructuring. So: collapse means widespread species and biosphere change, extinctions of large mammals. All this with relatively small forcings due to solar radiation changes.