ajaxified php mail not working

I'm running on a MAC and I am trying to use php mail with ajax implementation.

I have simplified my code to the point that it was reduced to strings:

In my .js file :

function ajaxMail2() {
 
 
 
         $('#sending').show();
 
 
         $.ajax({
 
             type:'POST',
             url:'ajax/mail.php',
 
             success:function(data, status) {
                 $('#sending').hide();
                 $('#success').fadeIn(1000,function() {
                     //$(this).delay(200).fadeOut(1000);
                 });
             },
 
             error:function(data, status, e) {
                 $('#sending').hide();
                 $('#fail').fadeIn(1000,function() {
                     $(this).delay(200).fadeOut(1000);
                 });
             }
 
         });
 
 
     }
 

and on my .php file :

<?php
 
 
 
 $to = 'foo@gmail.com';
 mail($to,'test','test');
 
 
 
 ?>
 

When the form is submitted, it goes to the success function but no email was sent to $to. Any ideas?

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