Table 3.

Upper Bound Needed on the Log Uniform Before Getting a High Probability of Intelligent Life

10% of posterior weight such that			50% of posterior weight such that
n	P(life) >1%	P(life) >10%	P(life) >1%	P(life) >10%
	2	104.8 Ga	103.1 Ga	101.8 Ga	101.2 Ga
3	102.4 Ga	101.6 Ga	101.2 Ga	100.8 Ga
4	101.8 Ga	101.2 Ga	101.0 Ga	100.6 Ga

Data used for transition dates were 4.2 Gya for start of habitability window, 3.8 Gya for abiogenesis (used in all three models), 1.8 Gya for eukaryotes (used when n = 3 and n = 4), 1.2 Gya for sexual reproduction (used when n = 4), and a total habitability window of 5.2 Ga. The other transition in all models was considered to be the evolution of intelligence close to present day.