JS Design patterns - Inheritance - Explicit prototype declaration, Object.create, method factory

inheritance-designPatterns.js

var Animal = {
  create(type){
    var animal = Object.create(Animal.prototype);
    animal.type = type;
    return animal;
  },
  isAnimal(obj, type){
    if(!Animal.prototype.isPrototypeOf(obj)){
      return false;
    }
    return type ? obj.type === type : true;
  },
  prototype: {}
};
var Dog = {
  create(name, breed){
    var dog = Object.create(Dog.prototype); 
    Object.assign(dog, Animal.create("dog"));
    dog.name = name;
    dog.breed = breed;
    return dog;
  },
  isDog(obj){
    return Animal.isAnimal(obj, "dog");
  },
  prototype: {
    bark(){
      console.log("ruff, ruff");
    },
    print(){
      console.log("The dog " + this.name + " is a " + this.breed);
    }
  }
};
Object.setPrototypeOf(Dog.prototype, Animal.prototype);