Siberian permafrost discovery reveals extinct rhinos that possessed unique saber-shaped weaponry.
A woolly rhinoceros horn unearthed from Siberian permafrost is the longest ever found, stretching 164.7 centimeters — twice as long and ten times heavier than modern Asian rhino horns. The saber-shaped find, from a female over 40 years old, offers fresh clues about how these Ice Age beasts lived and why females may have sported the biggest horns. Researchers describe the specimen in a study published September 12 in the Journal of Zoology.
“This suggests that Coelodonta antiquitatis may have had the longest horns in females, similar to modern-day African rhinoceroses,” the researchers write in the study. “This discovery not only provides insights into the morphological features of woolly rhinoceroses but also offers valuable information about their palaeoecology and sexual dimorphism.”
G.G. Boeskorov et al./Journal of Zoology 2025
The horn was spotted last summer by a local resident along the Mustur-Yuryuye River in Yakutia, Russia, poking out of thawing permafrost alongside a skull and frozen lemming remains. Radiocarbon dating of one lemming placed it around 19,700 years ago, during the peak of the last ice age, when frigid tundras dominated.
Woolly rhinos, shaggy relatives of today’s rhinos, roamed Eurasia until about 14,000 years ago. They had two horns made of keratin — the same stuff as human hair and nails — with the front nasal one far longer and flattened sideways, unlike the conical horns of modern species. Adults typically had nasal horns averaging about a meter long and weighing 6 kilograms, dwarfing those of living rhinos.
This record-breaker weighs about 9 kilograms and shows 40 to 41 alternating dark and light bands, each pair marking a year of growth like tree rings. That makes its owner the oldest known woolly rhino, living to at least 40, matching the lifespan of captive modern rhinos.
“The greater width of transverse bands in the distal part of the horn is interpreted as a sign of an increased growth rate at a young age,” the researchers note.
The skull’s modest size hints it was a female, suggesting sexual differences: males likely had thicker, heavier horns for fighting, while females grew longer ones, perhaps for defense or sweeping snow to reach grass in winter. The horn’s worn front edge supports this snow-shoveling idea.
Compared to modern rhinos, woolly ones had uniquely elongated horn bases, making them sturdier against abrasion. Yet this giant horn shows no unusual robustness, reinforcing the female theory.
Citations
R. I. Belyaev et al. The longest known rhino horn from the permafrost of Yakutia offers insights into woolly rhinoceros morphology, palaeoecology and sexual dimorphism. Journal of Zoology. Published online September 12, 2025. DOI: 10.1111/jzo.70064
