A new study seeks to explains why kangaroos and koalas never travelled from Australia to Asia, while other species were successful in travelling in the other direction.

Extra articles:

https://www.australiangeographic.com.au/news/2023/07/why-are-there-no-kangaroos-in-asia-its-a-long-story/

https://phys.org/news/2023-07-wont-kangaroos-java-goannas-australia.html

Biologists have long described an invisible boundary separating Australia, New Guinea and parts of Indonesia from continental South-East Asia.

In Switzerland, providing an explanation for why kangaroos and koalas aren’t found in Indonesia, but many groups of animals that originated in Asia, such as goannas, rodents and kookaburras, are in Australia.

“At some point in earth’s timeline, Australia broke away from Antarctica and over millions of years drifted north, causing it to crash into Asia.”.

The islands of Indonesia served as “Stepping stones” for animals and plants that originated in Asia to reach New Guinea and northern Australia, and vice versa.

“Our research shows far more groups of Asian fauna crossed over and established themselves in Australia than in the opposite direction,” Dr Skeels said.