New Research Reveals Extinction of Ancient Marine Species in Warm, Flooded South Pole
In a groundbreaking study, researchers have uncovered the mystery surrounding the extinction of the Malvinoxhosan biota, a group of marine animals that thrived during the Early-Middle Devonian period in the warm, flooded landmass of Gondwana at the South Pole. The research, conducted by Dr. Cameron Penn-Clarke and David A.T. Harper, has revealed a correlation between the decline of these species and changes in sea levels and temperatures.
Gondwana, which included parts of Africa, South America, and Antarctica, was located near the South Pole during the Early-Middle Devonian period. Contrary to the frigid environment we see today, this landmass experienced warmer weather and elevated sea levels that submerged a significant portion of its terrain.
The Malvinoxhosan biota were a group of marine animals that primarily thrived in cooler waters, including various types of shellfish. However, their origin and disappearance have remained a mystery for nearly two centuries. Dr. Penn-Clarke explains, “The origin and disappearance of these animals have remained an enigma for nearly two centuries until now.”
To unravel this mystery, the researchers collected and analyzed a vast amount of fossil data. They used advanced data analysis techniques to examine layers of ancient rock and sort them based on the types of fossils found within. By comparing these findings with changes in the environment, sea levels, and global temperature records from that time period, they discovered that the decline of the Malvinoxhosan biota was accompanied by several phases of diminishing species diversity.
According to Dr. Penn-Clarke, this research spanned over a decade and posed numerous challenges. Nevertheless, their persistence and perseverance led to significant insights into the extinction event. The researchers propose that the Malvinoxhosan biota survived during a period of global cooling, which allowed for the formation of circumpolar thermal barriers. These barriers isolated the animals, leading to their specialization. However, as the climate warmed, disruption in sea levels likely removed these barriers, allowing warm-water species to infiltrate the South Pole.
The invasion of warm-water species gradually replaced the specialized, cool-water Malvinoxhosan marine animals, resulting in their extinction. This event had severe implications for polar ecosystems, as the extinction of the Malvinoxhosan biota triggered an irreversible collapse in biodiversity in these regions.
Dr. Penn-Clarke emphasizes the importance of this research in understanding the current biodiversity crisis, stating, “It demonstrates the sensitivity of polar environments and ecosystems to changes in sea level and temperature. Any changes that occur are, unfortunately, permanent.”
The findings of this study also have broader implications for environmental changes in the polar regions. Similar declines in biodiversity controlled by sea-level changes have been observed in South America, highlighting the vulnerability of polar ecosystems to environmental shifts.
This research sheds light on a 390-million-year-old murder mystery, as Dr. Penn-Clarke puts it, and expands our understanding of the lasting impact of environmental changes on ancient ecosystems. The study, funded by the GENUS: DSI-NRF Centre of Excellence in Palaeosciences, the National Research Foundation, and the Leverhulme Trust, opens up new avenues for further exploration of the Earth’s history and its fragile ecosystems.