The researchers from University College London (UCL) that the Port Askaig Formation, consisting of a layer of rocks up to over 1km thick, was likely form between 662 and 720 million years ago during the first of two global ice ages that are thought to have stimulat the development of complex, multicellular life.
An expos piece of the rock, found on Scotland’s Garvellachs Islands, is unique because it shows the transition to Snowball Earth from an earlier warm, tropical period. Other rocks form around the same time, for example in North America and Namibia, do not show this transition.
Lead researcher Professor Graham Shields from UCL said: “These rocks show that the Earth was once completely cover in ice. All complex, multicellular life, such as animals, emerg from this deep freeze, with the first evidence in the fossil record dating from shortly after the planet thaw.”
Carbonate rocks
Researcher Elias Rugen adds: “Our study provides the first time a defin period for these Scottish and Irish rocks, confirming their global significance. The rock layers expos on the Garvellachs are unique in the world. Beneath the rocks that 2024 fresh whatsapp number lead were deposit during the unimaginably cold Sturtian (as the Ice Age is officially call, .) lie 70 meters of older carbonate rocks that were form in tropical waters. These layers show a tropical marine environment with flourishing cyanobacterial life that gradually became cooler, marking the end of the approximately one billion years in which the Earth had a temperate climate.”
Complex life
“In most parts of the world this remarkable transition is missing, because the ancient glaciers have scrap ល្បិច និងយុទ្ធសាស្ត្រដើម្បីបង្ហោះរឿង Instagram ឡើងវិញនៅឆ្នាំ 2023៖ ប្រើសក្តានុពលបំផុតនៃទីផ្សារឌីជីថល! and erod away the underlying rocks, but in Scotland, by some miracle, it is visible,” he says, amaz.
The Sturtian last about 60 asb directory million years and was one of two great ice ages that occurr during the Cryogenian (between 635 and 720 million years ago). In the billions of years before this period, life consist only of single-cell organisms and algae. But complex life then arose rapidly and most animals today are still very similar to those that evolv more than 500 million years ago.
