Why do flamingos eat with their heads upside down?

Flamingos have these plates on the edges of their beaks, called lamellae. The flamingo dips its head upside down underwater, and all the water and underwater organisms and plants rush inside the lamellae. The flamingo then presses its fleshy tongue against the inside of its bill, forcing the water out, leaving the insects and plants inside the lamellae, which the flamingo will then be able to eat.