Ancient Rhino Fossil Challenges Mammal Migration Timeline

A 23-million-year-old rhinoceros fossil, discovered in the Canadian High Arctic, is forcing scientists to reconsider theories of ancient mammal migration. The find suggests large mammals moved between continents much earlier than previously believed. Researchers unearthed the fossil on Ellesmere Island, Nunavut. This location lies far north of the environments where such rhinos were thought to live. The species is a precursor to the modern rhinoceros. The discovery has two major implications. First, it indicates these animals could tolerate cooler, darker Arctic conditions. Second, it implies that land bridges for migration existed earlier in Earth's history. This fossil provides crucial new evidence for when and how mammals spread across the globe. It will help paleontologists redraw the paths of ancient animal dispersal.