esulted from overcrowdedness in an experiment on mice, drawing parallels with societal collapse found in the human Megalopolis.</li>
	<li><b>Dunbar's Number</b>: A suggested cognitive limit of 150, to the number of people with whom one can maintain stable social relationships.</li>
	<li><b>Kessler syndrome</b>: A theoretical scenario in which the density of objects in low Earth orbit due to space pollution is high enough that collisions between objects could cause a cascade in which each collision generates