ORG
Further definition & clarification
Saturday, March 10, 2018, 10:15

"The defining characteristic of the deuterostome is the fact that the blastopore (the opening at the bottom of the forming gastrula) becomes the anus, whereas in protostomes the blastopore becomes the mouth. The deuterostome mouth develops at the opposite end of the embryo from the blastopore and a digestive tract develops in the middle, connecting the two."

"In many animals these early development stages later evolved in ways that no longer reflect these original patterns. For instance, humans have already formed a gut tube at the time of formation of the mouth and anus. Then the mouth is formed first, during the fourth week of development, and the anus is created four weeks later, temporarily forming a cloaca."

So actually, there was a point when you were all mouth, and it's similarly likely that some never develop beyond this stage . . . visit social media for proof.

:-) :-) :-)