Answer:
The last man on Earth received a phone call, who was the caller?
Lighter than what I am made of. More of me is hidden than seen. What am I?
Turns me on my backs and open up my stomach. You will be the wisest of men though at start a lummox.
An open ended barrel I am shaped like a hive. I am filled with the flesh and the flesh is alive.
I'm found in socks ties and hands. What am I?
No matter how little or how much you use me, you change me every month.