Dinosaurs Once Thrived in the Icy Landscapes of Southern Australia

For years, experts have been stumped by the fact that dinosaurs supposedly existed in southern Australia during the Early Cretaceous period. The proof of these beasts at the site was shocking because back then it was enveloped in darkness and wind, which typically are not conditions that dinosaurs can thrive in, stated Daily Galaxy. A team of researchers recently reconstructed what southern Australia possibly looked like back then and, in the process, found out how it served as a habitat for dinosaurs. These findings were published in Alcheringa: An Australasian Journal of Palaeontology. 

In the Early Cretaceous period, southern Australia was in a supercontinent that also included Antarctica. As per estimates, Victoria was 80 degrees south of the equator, inside the polar circle. Past examinations of fossils at the site have revealed that a host of dinosaurs managed to flourish here, despite the extreme conditions. Both herbivorous and carnivorous dinosaurs, like ornithopods and theropods, coexisted at the place. 

In the study, experts reconstructed what southern Australia possibly looked like in the Early Cretaceous period, according to Live Science. For this reconstruction, the authors took into consideration the insights they gained from the analysis of around 300 ancient pollen and spore samples, which they found on the Victoria coast. These samples were dated back to somewhere between 130 million and 110 million years ago. The examination helped the team figure out how forests and floodplains transformed over the years in the area, especially in places where dinosaur fossils were found. 

The reconstruction showcased that despite being enveloped in darkness, there were features that aligned perfectly with the needs of dinosaurs. Through the model, experts concluded that the 'polar dinosaurs' roamed in cool temperate forests containing rivers covered by massive ferns. Researchers further noted that even though the quantity of sunlight reaching the Antarctic Circle has remained the same, the climate was much warmer, making it easy for these dinosaurs to fulfill their life functions. 

Dinosaurs also adapted to the conditions of the area's environment, especially in terms of their diet. The model indicated ancient conifers were primarily present in the forest canopy, while ferns overtook the understory in the Early Cretaceous period. Around 113 million years ago, flowering plants started to make their way at the site. Flowering plants possibly led to the extinction of understorey plants and making Victorian forests an open conifer-dominated forest canopy. The species that grew in this system included lycophytes, liverworts, hornworts, and sphagnum-like mosses. The changing vegetation impacted the herbivorous dinosaurs, who expanded their diet to incorporate flowering species by the end of the Cretaceous.

The model aligns with what is already known about the Early Cretaceous (140 million to 110 million years ago) period. Past examinations have revealed it to be one of the warmest periods in the last 500 million years of Earth's history. Vera Korasidis, a lecturer in environmental geoscience at the University of Melbourne and a research associate at the Smithsonian's National Museum of Natural History, further claimed that there were also no ice caps during that time. All of these attributes helped dinosaurs thrive in this area before an asteroid impact wiped them from existence.