Cargo bird
Cargo Birds are large, intelligent, avians of various species who are raised and trained to carry small and light packages, letters and other cargo between cities on the planet of Offworld. Although they don't talk, they are capable of fully understanding and comprehending all of the major languages on the planet, including English, Bonisi, German, Dutch and several others. They're treated as a light weight air mail service, carrying loads of no more than 20lbs for the biggest birds, and 5lbs for the smallest, between locations, although some of the largest birds have carried loads up to 50lbs over short distances. Most birds, though, carry on average no more than 15lbs per trip and typically fly no more than 10-20 miles on most deliveries, but can go as far as 200 miles if required. Beyond those distances the package must be transferred to a fresh courier to continue the journey. Notable users of the cargo bird are Alexander Baker, Susan Wheaton and Benjamin Bernstein. Cargo Birds are biomechanoids and were created by the controllers. However, nobody is quite sure why, as they are one of the few biomechanoids on the planet who are not given any particular task to do by their creators, nor are they given any implants at birth, or at any point in their life. Yet their advanced genetics still allow them to maintain their high level of intelligence despite this. They are also highly popular among the residents of Offworld due to their incredible usefulness.