New dinosaur fossils found in Kyrgyzstan reveal parenting behavior

Researchers have discovered the first giant predatory dinosaur fossils in Kyrgyzstan, named Alpkarakush kyrgyzicus, which is a distant relative of Tyrannosaurus rex. Excavations began in 2006 in a mountainous desert region near Tashkumyr, revealing fossils from two individuals, likely a parent and its offspring. The larger specimen measured approximately 26 feet long and weighed over 2,700 pounds, while the smaller was 15% to 20% smaller, indicating a close relationship between the two. The fossils, which include nearly complete hind limbs, skull bones, and vertebrae, showcase unique features such as a prominent orbital brow. Researchers utilized growth rings in the bones to estimate the ages of the dinosaurs, concluding that the larger specimen was at least 17 years old and the smaller was a juvenile. This association suggests that young Alpkarakush traveled with adults during their early subadult stage, indicating a level of parental care. The discovery of A. kyrgyzicus fills a significant gap in the understanding of Jurassic theropods, particularly in Central Asia, where such fossils had not been previously identified. The findings contribute to the broader knowledge of the evolution and biogeography of carnivorous dinosaurs, particularly those in the Metriacanthosauridae family. The study, published in the Zoological Journal of the Linnean Society, encourages further research into these fossils, with the authors sharing 3D models to facilitate additional examination by other scientists. This collaborative effort aims to deepen the understanding of Jurassic ecosystems and the behaviors of these ancient creatures.