Do you think it was

 Some sugar cane in the garden of eden 

Probably wasn't that many

 Words formed at that time 

And Abel

 Was able to 

But possibly

 Sugar cane 

So Cain

 Since it probably wasn't cocaine 

So we read what happened

 But their names

Abel sheep

 He gave the first one to God 

Cain started doing whatever

 Then thought about God 

So now name

 Cain and able 

God could have told

 Somebody else to build the ark there was other people 

God didn't tell you to build a ark

 He told Noah