Recent observations suggest that scientists have identified potential microbial fingerprints in the atmospheres of other planets, raising intriguing questions about the possibility of alien life ...

Introduction: Nonnative species in the world / David Pimentel -- The impacts of alien plants in Australia / Richard H. Groves -- Environmental and economic costs of invertebrate invasions in Australia ...

Phosphine gas detected on Venus suggests the presence of oxygen-free microbial life, though findings are still unconfirmed. Such life would be invisible to the naked eye and fundamentally different ...