Silverfish are those little peices of crap you see before entering the End. They spawn and then spawn more of themselves from blocks that already has a silverfish in it. They dont seem to have an explainaton for them so Im going to give one. Oh, before we get started I want to say sorry for not uploading in a while I went to Scotland and then California for a long time. Any way enough excuses, lets go right on into this well wrote and very acurate theory.

Every time I am in a dungeon I always wonder why a silverfish is guarding a portal. They dont seem to be, in any way, realated to the End. That isnt true. There is another annoying mob know as the (skeleton) endermite. They first looked like silverfish but purple then turned into a little End slug. They have a pretty rare chance of spawning from an enderman which is also intersiting. SIlverfish seem like they can only spawn from one another making them rare as well. As for why they are found at the End portal is because they first came from the End. Everything must adapt to its enviornment and the silverfish being in a place filled with rocks where able to burrow into them as a worm does to dirt. Have you ever seen that movie with those giant mutated worms with pads all around them so the can move through the dirt? i think silverfish do the same thing but with stone.

Sorry if this was really short and also really bad but its late and I wanted to do something on here. I hope I dont seem like that kid who thinks he knows EVERYTHING about minecraft. Oh before u go I made a silver fish skin so dont forget to leave a hate coment on that as well.