This is birdnode. Birds lay eggs. That means they don't nurse their young, right?

Well, have you ever heard of something called pigeon milk?

Pigeons, one of the most ancient of domesticated birds, feed their nestlings a peculiar milky liquid

straight from the adult's beak to the baby's throat.

It's often called crop milk because it comes from special cells in the bird's crop.

The crop's a section of the lower esophagus in some birds that's used for storing food before digestion.

Unlike milk from mammals, pigeon milk doesn't come from a mammary gland,

but it does come loaded with antioxidants and immune boosters that help the new hatchling survive.

A couple of days before their eggs hatch, both pigeon parents start making the milky substance,

which they'll feed their hatchlings over the first ten days of their lives.

When the special feeding stops, the special crop milk cells return to normal.

Pigeons and doves aren't the only birds that can make this special milk.

Flamingos and some species of penguins can too.

For birdnode, I'm Michael Stein.

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