Every one started out first being an asshole.
Yes, the anus is the first body part to develop. A group of cells called the BLASTULA burst open from inside out to form BLASTOSPORE which is the medical term for anus.

So without much ado this is the order in which the body develops in the womb;

1; The Anus
2; The Nerve Cells
3; The Brain And Spine
4; The Placenta
5; The Heart
6; The Limbs
7; The Face
8; The Eyes
9; The Genitals
10; The Teeth(babies are born with all their adult teeth in their skull)
11; The Hands And Feet
12; The bones
13; The Finger And Toenails
14; The Muscles
15; The Internal Organs
16; The Outer Ears
17; The Eye Brow And Eye Lash
18; The Fingerprint
19; The Lungs

NB 1; Some people never outgrew their first stage, they are still assholes
NB 2; DO NOT GOOGLE BABY SKULL IMAGE. THAT SHIT IS SCARY

Cc; lalasticlala