I remember reading in Model Railways that smaller stations in England actually had a “shunt horse” to handle the two or three wagons they got daily. A good draft horse was more than up to the task for that kind of traffic. The horse would be a challenge as a working model, though.
Also read in National Geographic once that a small oil refinery in India hired out two or three elephants and their handlers while their small diesel shunter was gone for repairs. The shunter returned, but was mothballed. The refinery liked the elephants better, since they could also line the switches with their trunks! Another challenge to build a working model.
Trish, the work triceratops, is strictly static.

Regards, David Meashey