Rare fossil shows non-avian ankylosaurs might have sounded like birds

A remarkable fossil sheds light on a pivotal moment in the evolution of our world: when some dinosaurs began to migrate toward their avian descendants. It is now believed that Ankylosaurs had evolved voice boxes capable of producing certain bird-like vocalizations as far back as during the Cretaceous Period. As per researchers, this discovery is one of science's oldest laryngeal fossils!

Rare voice box specimens

Against the odds, a remarkable 84-72 million-year-old fossil of an ancient larynx from Pinacosaurus grangeri has been discovered, marking it as one of the most exceptional specimens in history. This resilient respiratory remnant is incredibly rare, being part of such fleeting tissues that rarely survive and make their way into our planet's fossil record. 

Recent research confirms this unprecedented discovery to be true - making it by far the oldest known larynx specimen on Earth!

Usually, birds consist of a particular respiratory equipment set known as syrinx. It is found at the base of the bird's trachea. This enables them to make sounds without the need for vocal folds found in mammals. 

Pinacosaurus, a species of ankylosaur studied by researchers, didn't possess the classic syrinx like other animals to produce sound. However, its large and kinetic larynx served a key purpose - airway protection! 

Unlike creatures that rely on their voice box for closing off the glottis (to keep foreign materials out), Pinacosaurus' larynx kept it open instead; this allowed airflow regulation similar to bird vocalization patterns which could be used to modify sound production.

Four features similar to birds' syrinx

The Pinacosaurus larynx boasted four features similar to the syrinx of birds like parrots and passerines - a remarkable feat representing an evolutionary milestone between tetrapods and modern avian creatures. 

Its shape is now considered the closest analog ever discovered in a non-avian dinosaur, offering new insight into how our current respiratory structures evolved over time.

Early dinosaurs were believed to be equipped with vocalizations as sophisticated and diverse as their reptilian successors, enabling them to communicate in courtship displays and warning calls. 

These powerful sounds would have enabled these ancient creatures to defend themselves against predators while also asserting territorial boundaries, behavior similar to many animals today!