An example of concatenative inheritance

AnimalAndDog.js

var animal = {
  position: [0,0],
  species:  "mammal",
  move: function(distance, axis) {
    axis === 'x' 
    ? this.position[0] += distance
    : this.position[1] += distance;
  }
}


var dog = _.extend({}, animal, {
  species: "canine",
  bark: function() {
    alert("woof!");
  }
});

Instead of lodash _.extend in ES6/2015 you can know use Object.assign()