Shark Tales and Ice Ages

Sharks and their relatives are apex predators in our modern-day oceans and play a vital role in keeping marine ecosystems healthy but are declining in diversity. They first appeared over 450 million years ago in what is known as the Palaeozoic era and diversified into many of the groups that still exist today. However, our knowledge on their early biodiversity patterns is poorly known because their predominantly cartilaginous skeletons rarely fossilize, leading to large gaps in their fossil record. Understanding past diversity patterns may be the key to assess current conservation measures.

During the last-ice age, the planet was 2-4 times dustier than just before the Industrial Revolution. This was partly because plants struggled to grow in a colder, drier climate. Surprisingly, the largest change in dust was over the poles where it was as much as 50 times dustier. Yet computer models of Earth's climate fail to reproduce these large polar changes. Here we'll journey through data from the past, from today's deserts and into the computer models used to understand future climate, to look at how the ancient climate state might hold some clues to the immediate future.