a few steps for a database with polymorphic association?

rubyonrails-talk
1

I thought it could be created in a few steps but it can't yet:

    rails poly     cd poly

    ruby script/generate scaffold animal name:string obj_type:string obj_id:integer     rake:migrate

    ruby script/generate scaffold human name:string passportNumber:string     rake:migrate

    ruby script/generate scaffold dog name:string registrationNumber:string     rake:migrate

and now change app/models/animal.rb to:

    class Animal < ActiveRecord::Base       belongs_to :obj, :polymorphic => true     end

and run

    ruby script/server

and go to

    http://localhost:3000

I thought on the server then if I create an Michael, Human, J123456 and then Woofie, Dog, L23456

then the database will have entries in the Dogs table and "Humen" or "Humans" table as well as in the Animals table? But only the Animals table has records, Dogs and "Humen" do not for some reason. Is there some steps missing?