Why has the novel ended with Somax and Beauty, one of his mules ? What is Malouf saying to the reader by this choice ?

In the aftermath, after the end of the main story, after Troy falls, the only person left is Somax. While all the illustrious people in the story pass away, the carter lives on. As time goes on, the tale that only the carter knows becomes less and less believable. In the end, the simplest piece of the story—Beauty, the mule—is the best is preserved. Priam's intuition was right: it is the humble things that last.