How to deserialize data from Firebase with inheritance in AndroidStudio

I'm doing a very simple app to learn how to use FireBase correctly.

My problem comes when I want to deserialize objects that inherit from X classe.

Example:

The AnimalManager class will be the one containing my ArrayList

The classes [Tiger.class, Dog.class and Cat.class] extend from Animal

The problem is that FireBase does not care about inheritance and when I deserialize my class AnimalManager.class all objects are animal so the specific attributes are not loaded it saves them as if they were all Animal. That means that I no longer have dogs or cats or simply animal tigers.

That's the way I suppose FireBase works and saves like this:

So after realizing it I decided to change the way to do it and use: HashMap I thought it works now! But now I have neither dogs nor cats nor Tigers. They're all Object, so even though they're saved better now, it's no use either:

My init method was as follows:

   public void init(){
    this.animals.put("Gatos", new ArrayList<Object>());
    this.animals.put("Perros", new ArrayList<Object>());
    this.animals.put("Tigres", new ArrayList<Object>());
}

So this does not work since they are Object and not Cat, Dog or Tiger

Then I decided to use generics:

public class AnimalManager implements Serializable {

private HashMap<String, ArrayList<? super Animal>> animals = new HashMap<>();

public AnimalManager() {
}

public void init(){
    this.animals.put("Gatos", new ArrayList<>());
    this.animals.put("Perros", new ArrayList<>());
    this.animals.put("Tigres", new ArrayList<>());
}

public HashMap<String, ArrayList<? super Animal>> getAnimals() {
    return animals;
}

public void setAnimals(HashMap<String, ArrayList<? super Animal>> animals) {
    this.animals = animals;
}

public void addAnimal(String key, Animal o){
    //this.animals.get(key).add(g);

    if(o instanceof Gato){
        Gato g = (Gato) o;
        this.animals.get(key).add(g);
    }else if(o instanceof Perro){
        Perro p = (Perro) o;
        this.animals.get(key).add(p);
    }else{
        Tigre t = (Tigre) o;
        this.animals.get(key).add(t);
    }
}

But then FireBase sends me another error! com.google.firebase.database.DatabaseException: Generic wildcard types are not supported

So is there any way to get this? I want to have an Animal ArrayList of my application in the same array but always keeping in mind that they are Cat, Dog or Tiger

Thank you!