55-Million-Year-Old Owl Skeleton Sheds Light on Early Evolution
An exceptionally complete 55-million-year-old fossil owl has been described, offering unique insights into the lifestyle of early owls. The fossil suggests a different hunting method compared to modern owls.
Scientists at the Senckenberg Centre for Human Evolution and Palaeoenvironment have described a new fossil owl species, Primoptynx poliotauros. The 55-million-year-old skeleton is the oldest, most complete fossil from the early stages of owl evolution, providing unique insights into the birds' lifestyle.
The discovery, made by Senckenberg scientist Gerald Mayr with international colleagues, significantly enriches the understanding of owl origins. Previously, only isolated bones and fragments from early owls were known. This new, nearly complete skeleton was found in the North American Willwood Formation and is estimated to be 55 million years old.
Primoptynx poliotauros was approximately the size of a modern snowy owl. However, its talons differed significantly from those of modern owls. While extant owls have talons of similar size on all toes, this extinct species had noticeably enlarged talons on its hind toe and second toe. This talon proportion is known from diurnal raptors like goshawks and eagles.
Researchers hypothesize that Primoptynx poliotauros used its talons to kill prey, unlike modern owls which use their beaks. This suggests a notable difference in hunting behavior. The finding also reveals the diversity of owl species in early Eocene North America, ranging from the small Eostrix gulottai to this large new species.
The reasons for the evolutionary shift in hunting technique remain unclear. Scientists speculate that competition with diurnal raptors around 34 million years ago may have influenced owls' specialization and potentially contributed to the development of their nocturnal habits.