https://phys.org/news/2018-10-mammals-evolve-fast-current-extinction.html?fbclid=IwAR2o1IHPN-7p4Ba2L_VNE2anFUR3G_uLer4QxdoZczZ_vN6eKgFzr1-CjGc A research team calculated that if current conservation efforts are not improved, so many mammal species will become extinct during the next five decades that nature will need 3 to 5 million years to recover. Read more at: https://phys.org/news/2018-10-mammals-evolve-fast-current-extinction.html#jCp