Clean URL's not respected on local
It may be that your Apache vhost and/or .htaccess need updating.

Yosemite uses Apache 2.4, which replaces some access control statements used in 2.2 and prior.

'Allow from all' becomes 'Require all granted'

'Deny from all' becomes 'Require all denied'

See htaccess protections do not work on Apache 2.4 without mod_access_compat for the ongoing Drupal 7 core discussion. Upgrading to 2.4 from 2.2 gives some guidance on upgrading configurations.