Complex sentence: Camels were the primary means of bulk transport in the outback (where the climate was too harsh for horses and other beasts of burden) prior to the widespread adoption of motor vehicles, and a large population of Australian feral camels remains from this time.
Split into simpler sentences: Camels were the primary means of bulk transport in the outback (where the climate was too harsh for horses and other beasts of burden) prior to the widespread adoption of motor vehicles. A large population of Australian feral camels remains from this time.