It's been around for millions of years, but it's no more than a month old. What is it?

He’s the worst pirate you’ve ever heard of, But you have heard that he set slaves free. He traded his soul to the depth of the ocean, To pull the Wicked Wench from the sea. With Davy Jones he struck a bargain, Thirteen years to sail, then service to keep. Now name the small bird that shares a title, With the man who returned from the deep.

First two are short for below average height Last two are another way to say morning Together, it's soil that's just right To make sure your garden avoids scorning

I’m small and dark, yet ground for bite, often beside my friend in white.

I hold secret words and valuable letters, but I am only secured by trust. I can also hold junk, but I'm not a trash bin. Sometimes large, sometimes small, sometimes flat, sometimes... less flat. Take away my last letter and you'll discover what I do to my contents.