A few steps for a database with polymorphic association?

Rails
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?