Flamingo can only eat when its head is upside down

Flamingo is one of my favourite birds. My favourite species of flamingo is Greater Flamingo. Mostly, we can see flamingos in Africa especially Lake Nakuru at Kenya 🇰🇪 and some in Italy 🇮🇹 and even France Camarague River. 🇫🇷

How is this bird's head upside-down?

Having to eat like that, is not proof they won't be able to eat any other eat!

I have a friend that adores the bird cant wait to ask him.