I’ve been (publicity) scooped! Clearly ignoring the power of synergy, Yale geologists pre-empted the unveiling of my blog and presented their model predicting that the next supercontintent dubbed, Amasia, will form near the North Pole. Continents are fidgety by nature and have been moving around for billions of years. The last supercontinent, Pangaea, formed 300 million years ago while Rodinia existed about 1 billion years ago. The oldest known supercontinent, Nuna (aka Columbia) formed 1.8 billion years ago. The Yale team modeled the movements of these past supercontinents by using a combination of paleomagnetism and polar wander like a paleo-GPS to obtain longitudinal and latitudinal positions. Paleomagnetism as Charles Q. Choi explains is “the impact that Earth’s magnetic field has on ancient rocks. Magnetic minerals in molten rock can act like compasses, aligning with the planet’s magnetic field lines, an orientation that gets frozen in place once the rock solidifies. Since these lines generally run north-south, looking at the way these minerals point can shed light on how the landmasses they are a part of might have drifted in space over time.” Their prediction of where Amasia will form is extrapolated from their modeling of how past supercontinents formed. But don’t hold your breath, it’s not expected to happen for another, oh, 50-200 million years.
Geology and Biology: Helping Hands
The study of geology and biology have long been complementary. For instance, the break up of Rodinia coincides rapid global cooling, changes in atmospheric oxygen as well as changes in ocean chemistry that may have jumpstarted the Cambrian Explosion, the rapid appearance and evolution of the majority of animal phyla that occurred around 500 million years ago. The appearance of the same (or similar) species in the fossil record in areas separated by great geographical distance supports the existence of past supercontinents. For instance, fossils for Lystrosaurus have been found in Africa, India and Australia, providing fossil evidence for the existence of Pangaea. The prospect of a new supercontinent will have profound impact on evolutionary biology as newly-formed environmental niches will be exploited while new interactions between species previously isolated by geography will occur. Too bad none of us will be there to confirm the prediction.