Is a human appendix homologous structure?

Yes, the human appendix is considered a homologous structure. Homologous structures are structures in different organisms that are similar in structure due to shared ancestry. In the case of the human appendix, it is homologous to the caecum, which is a pouch-like structure found in the digestive system of many other mammals. Although the appendix has no apparent function in humans, it is believed to be a vestigial structure, meaning that it is no longer essential for survival and has become reduced in size and complexity over the course of evolution. The presence of the appendix in humans and its similarity to the caecum in other mammals suggests a common ancestor and evolutionary relationship.