The Bulletin of the Atomic Scientists have moved their Doomsday Clock to 89 seconds to midnight.

The clock symbolically illustrates how close humanity is to the end of the world.

Canterbury University professor Jack Heinemann says escalating global tensions have increased the threat of nuclear war - and lack of action on climate change has raised concerns too.

"What they've drawn particular attention to this year is the uncontrolled possibility of further disruptions to our biological ecosystems - not just through the spontaneous occurrence of a new kind of pathogen... but also because we are developing, very rapidly, our use of gene technology."

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