Monophyletic group

A monophyletic group is a collection of organisms that includes an ancestor and all of its descendants, and only those descendants. Imagine a family tree: if you pick a single ancestor and all the lines branching out from that ancestor, encompassing every branch without excluding anyone, you've identified a monophyletic group. This concept helps scientists understand evolutionary relationships clearly, showing how species are related through common ancestors. It's a way of grouping organisms based on shared evolutionary history, ensuring the group reflects a natural, complete lineage.