the expense of many other species occupying Earth today. Between 1970 and today, populations of wild vertebrates have declined 60%; similarly sharp declines may have occurred among insects and vascular plants, although the evidence is sketchier. So our successful efforts to increase human carrying capacity have come at the expense of Earth’s capacity to sustain other species. As we have converted habitat and resources to our own use, other species have sharply declined—to the extent that conservation biologists speak of an incipient mass species extinction. Second, expansions in per capita wealth and the concomitant increases in per capita consumption, resource use and waste generation, tend to decrease the total number of people that can be sustained, long term. All else being equal, a richer population, living more luxuriously, has a lower carrying capacity than a poorer, more abstemious population. As affluence goes up, population must come down to remain within any theoretical carrying capacity, and vice versa. See also Tourism carrying capacity Inflection point Overpopulation in wild animals Overshoot (population) Population ecology Population growth r/K selection theory Toxic capacity ecological footprint and biocapacity Further reading Kin, Cheng Sok, et al. "Predicting Earth's Carrying Capacity of Human Population as the Predator and the Natural Resources as the Prey in the Modified Lotka-Volterra Equations with Time-dependent Parameters." arXiv preprint arXiv:1904.05002 (2019). References Demographics indicators Ecological metrics Population ecology Economic geography Ecological economics Environmental terminology