grow dark

In the 1800s, the sky would routinely grow dark when large numbers of the now-extinct passenger pigeon passed through this popular roosting area in northwestern, Pennsylvania.

I saw his face grow dark with anger.

But as it starts to grow dark, a large share of the crowd crossing the border are men who come mostly empty-handed.

The world was beginning to grow dark again.

What tells some skin cells to grow dark hair and others lighter hair?