Research overview: the frozen cave lion cubs Sparta and Boris from Yakutia

This overview describes two remarkably preserved cave lion cubs, nicknamed Sparta and Boris, recovered from the permafrost of Yakutia in northeastern Siberia. Frozen for tens of thousands of years, the cubs retained fur, skin, claws, whiskers, and internal soft tissues, offering an extraordinary direct look at the appearance of Panthera spelaea that bones alone cannot provide. The survey reviews what the specimens reveal about cave lion coat colour and texture, body proportions of young animals, and developmental stage at death, as well as the ages indicated by radiocarbon dating. It discusses how such exceptional mummified finds complement skeletal, genetic, and artistic evidence, and why frozen cubs are among the most valuable discoveries for reconstructing the biology of the Ice Age cave lion.