JSFiddle - React, Tailwind, and code Playground
JavaScript
var array1 = Array('birds','cats','dogs');
var array2 = Array('cows','horses','whales');
// function to migrate from one array to another - appending to the end of new array
function migrate_to_array(newarray,oldarray,index,key){
newarray[key] = oldarray[key];
oldarray.splice(index,1);
}
migrate_to_array(array1,array2,1,1);
alert(array2);