Plummeting Tortoises are a reptilian species from planet Kwikduk and the Milky Way galaxy’s best known case of Aggressive Evolution. Fed up with birds dropping them onto rocks to break their shells and get at the soft bits inside, Plummeting Tortoises evolved wings; so that the birds of Kwikduk suddenly found tortoises dropping on them – and their eggs. There are now no birds on Kwikduk.
Advertisement