Supporters of the water birth technique say primitive reflexes keep babies from taking a breath until they are removed from the water.

BBC: Water birth drowning risk

The primitive fish mouth straining for water and finding it as my son releases it in the shallows.

NEWYORKER: The Other Place

He thus put together a collection of apparatus that would not have disgraced the set of a mad-scientist horror film, and filled it with a mixture of methane, ammonia, hydrogen and water vapour that matched contemporary ideas of what the primitive terrestrial atmosphere had been composed of.

ECONOMIST: Stanley Miller