 The human gut microbiota has been linked to a variety of diseases, including metabolic disorders such as obesity and type 2 diabetes, autoimmune diseases like inflammatory bowel disease and type 1 diabetes, and cancers. Mice are often used as a model system to study these relationships, but there are some important differences between the human and mouse gut microbiotas. A recent meta-analysis of existing data suggests that the core gut microbiota of both species share many similarities, but also differ in certain aspects. Additionally, external factors such as diet and environmental exposure can affect how well mouse models can replicate human disease states. Alternative model systems, such as pigs or zebrafish, may offer more accurate representations of human gut microbiota dynamics. This article was authored by Phylone on New Yen, Syovira Silva, Adrian Liston, and others.