apply

function Cat(name,color){
Animal.apply(this, arguments);
this.name = name;
this.color = color;
this.eat=function(){
alert("吃老鼠11")
}
this.species = "动物12313";
}

function Animal(){
    this.species = "动物";
}

Cat.prototype.type = "猫科动物";
Cat.prototype.eat = function(){alert("吃老鼠")};

var cat1=new Cat("yang","13");

alert(cat1.species)//动物12313