Answer:
Although a human shape I wear, mother I never had. By every miss I'm valued much, still my cruel fate is such by boys I am often despised. What am I?
I am a desire to munch
Turns me on my backs and open up my stomach. You will be the wisest of men though at start a lummox.
I am lighter than the material I am made of. You see parts of me but more of me is hidden underneath.
It's been around for millions of years but is never more than a month old. What is it?
I am your mother's brother's only brother in law. Who am I?