The large community helps ensure that the operating system, and the products it supports, are well tested, and (through the open source philosophy) improved and supported.

So seals and dolphins as well as large fish and turtles need to keep an eye open at all times.

Modern large-mouthed snakes, such as boas and anacondas, can eat large prey because their jaw joints are positioned well behind their skulls, allowing the snakes to open their mouths very wide.