New revelations about woolly rhinos are emerging from the longest horn ever discovered, offering a glimpse into the lifestyles of these extinct creatures.
The remarkable horn, which was found preserved in Siberian permafrost, measures over 1.6 meters, making it nearly the height of a small adult human and 30 centimeters longer than the previous record holder, as documented by researchers on September 12 in the Journal of Zoology.
A local hunter stumbled upon the horn and an intact skull along a minor tributary of Russia’s Kolyma River. Afterward, he transported the specimens to the Mammoth Museum in Yakutsk for analysis. Nearby, frozen lemming remains were carbon dated in Novosibirsk, revealing that the findings date back approximately 19,600 years.
Woolly rhinos (Coelodonta antiquitatis), ancestral to modern rhino species, last shared a common ancestor with the Sumatran rhino roughly 9 million years ago. According to Ruslan Belyaev, a vertebrate zoologist at the A.N. Severtsov Institute of Ecology and Evolution in Moscow, this ancient horn surpasses the lengths of any contemporary rhinoceros horns.
Interestingly, the gargantuan horn did not originate from an extraordinarily large individual. The skull that held the horn is relatively smaller for an adult woolly rhino, leading researchers to speculate it likely belonged to a female. In modern rhino species, males tend to be bigger than females, and while male woolly rhinos appeared to have thicker horns, it’s possible for females to have longer horns, similar to certain African rhino species. Whether this length results from quicker growth or slower wear remains uncertain, Belyaev notes.
Moreover, the rhino was advanced in age at the time of its death. Rhino horns grow from the base, forming layers of keratin that alternate in color according to seasonal changes, much like tree rings. By examining these layers, researchers determined that this rhino lived for at least 40 years, making it the oldest woolly rhino discovered to date. This age exceeds the maximum lifespan usually found in modern wild rhinos and is comparable to the oldest captive specimens.
“For the first time, we have demonstrated that woolly rhinos could live as long as modern species, even under the harsh conditions of the Ice Age,” Belyaev states.
The substantial length of the horn likely played a crucial role in the survival of woolly rhinos. Unlike their modern counterparts, it’s theorized that these ancient creatures utilized their uniquely flattened, saber-shaped horns to clear snow while foraging for food. The wear observed on the front of woolly rhino horns in this study extended nearly halfway up from the base, according to Gennady Boeskorov, a paleontologist at the Diamond and Precious Metals Geology Institute in Yakutsk.
Luca Pandolfi, a paleontologist at the University of Pisa in Italy, who was not involved in this research, ponders whether woolly rhino horns could yield insights into ancient climate changes. It would be intriguing to discover if climate had any influence on the characteristics of horns and whether colder winters were reflected in the growth rings.
