Orangutans have the longest birth gap among mammals; a 2018 study explains how their 7.6-year wait for another baby, scarce forest fruit and solitary life may actually help them survive

Orangutans face rapid decline with fewer than 11,900 individuals remaining. Females reproduce slowly, averaging over seven years between births. This slow reproduction is tied to high infant survival and difficult forest food conditions. Their solitary arboreal lifestyle also contributes to reduced mortality risks. This slow life history makes orangutan populations vulnerable to drastic habitat changes.