javascript ineritance

/*
output:
flappie flappie
egg layed
swimmy swimmy
walkie walkie
eww, worms
nom, nom
swimmy swimmy
swimmy swimmy
nom, nom
undefined
*/
function Bird(){
  this.layegg = function (){
    console.log("egg layed");
  }
  this.walk = function(){
    console.log("walkie walkie");
  }
}

Bird.prototype.eatWorms = function(){
  console.log("eww, worms");
}

function Penguin(){
  Bird.call(this);
  this.swim = function(){
    console.log("swimmy swimmy")
  }
}

Penguin.prototype = Object.create(Bird.prototype);

function Duck(){
  Bird.call(this);
  this.fly = function(){
  console.log("flappie flappie")
  }
}

duck1 = new Duck();
duck1.fly();
duck1.layegg();

penguin1 = new Penguin();
penguin1.swim();
penguin1.walk();
penguin1.eatWorms();
Bird.prototype.eatFish = function(){
  console.log("nom, nom");
}
penguin1.eatFish();
penguin1.swim();

penguin2 = new Penguin();
penguin2.swim();





penguin2.eatFish();