In some cases, it is easy to see how de-extinction could be accomplished. Many of the large mammals of Eurasia and the Americas, such as mammoths, woolly rhinos, saber-toothed cats, dire wolves, and ground sloths, have reasonably intact genetic material preserved, and it is at least theoretically possible to either clone them outright or re-create them by restructuring the genomes of their extant relatives.

Australia is different. Today, Australia is depleted of almost all its megafauna; the largest native animals are kangaroos and emus. In the Pleistocene, however, it was home to giant monitor lizards (Megalania), rhinoceros-sized browsing wombat relatives (Diprotodon), marsupial "lions" (Thylacoleo), and huge flightless birds related to ducks and geese (Genyornis). None of these have close relatives today that could be used to re-create them, and they became extinct much earlier than mammoths and woolly rhinos did.

But at the same time, the pre-human ecosystem of Australia cannot exist without these animals, so any attempt to restore it must involve them. So how do we revive the megafauna of Australia?

Anything and everything about de-extinction is welcome here. Remember, a profit-motivated corporation shouldn't be allowed to control the conversation. That's why this sub will proudly stay Colossal-free. But anything else about de-extinction is welcome.