Well we all learned at school the classic evolutionarily theory

From:          To: 
fish           amphibian
amphibian      reptile
reptile        mammal
reptile        bird

But what always interested me:
What about non vertebrates?
Do they also have some evolutionary table like vertebrates or was there evolution never that interesting to begin with?
I can roughly imagine that there are giant evolutionary gaps between an insect and a jellifish but is there any common ancestor of all of them?

So my question has essentially two parts:

1. What is the common ancester between vertebrates, arthropods and molluscs
2. Is there an evolutionary Tree for the last two like for the vertebrates

Well we all learned at school the classic evolutionarily theory

From:          To: 
fish           amphibian
amphibian      reptile
reptile        mammal
reptile        bird

But what always interested me:
What about invertebrates?
Do they also have some evolutionary table like vertebrates or was there evolution never that interesting to begin with?
I can roughly imagine that there are giant evolutionary gaps between an insect and a jellifish but is there any common ancestor of all of them?

So my question has essentially two parts:

1. What is the common ancester between vertebrates, arthropods and molluscs
2. Is there an evolutionary Tree for the last two like for the vertebrates