Biologists have identified a series of "hard steps" on the long journey from abiogenesis to the modern technological civilization of humanity, such as the evolution of multi-cellular organisms or language. A new paper suggests all those steps weren't actually that hard or improbable and might have been an inevitable outcome of life's interactions with its environment. Key evolutionary states were possible when the global environment reached certain milestones.

Does planetary evolution favor human-like life? Study ups odds we’re not alone | Penn State University

Humanity may not be extraordinary but rather the natural evolutionary outcome for our planet and likely others, according to a new model developed by researchers at Penn State for how intelligent life developed on Earth.

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