troubles with get_avatar

I am using a third party theme that, for some reason, does not have working avatars. The code seems simple but does not work for whatever reason.

Is there anything upstream I can look for in code that may cause avatars to not work?

I know this is a really generic question but I am not a themer or WordPress guru.

This is the code that is trying to get the avatar for an author bio at the bottom of a post.

<?php echo get_avatar( get_the_author_meta('email'), '70'); ?>