Do penguins push one penguin in the water to test whether there are Leopard Seals around? : 2006-01-08
No, they definitely do not do this, although it may look that way to the casual observer. What happens is that penguins like Adelie Penguins congregate at the water's edge – and despite their marvellous adaptations for a life in water, they can often appear reluctant to enter it. Eventually one or two will dive in: whereupon the rest may or may not choose to follow.