well ok. You have to make a link between "Lion" and "Animal". How do you manage this? You could use a condition like IF IN ("LION","TIGER","EAGLE",etc) then "ANIMAL"
And you don't need to add field.
For the collect problem you have to simulate the solution that's means use a variable to remember that a Tiger is an Animal and sum this value to the Animal category.
Without your code functional specifications it's hard to help with a complete solution.
Hope to help
Bye