Every year, global temperatures keep breaking records, bringing more heat waves and droughts. Extreme weather is becoming the new normal, affecting people, wildlife, and ecosystems around the world.
A big question is how life on Earth will cope with climate change and to what extent it can adapt.
While today’s warming trend is clearly linked to human activities since the mid-1800s, Earth’s climate has always been on flux, with past periods warmer than today. The Eemian interglacial (about 125,000 years ago) and the mid-Pliocene warm period (around 3 million years ago) were such warm phases, driven by natural climate variability and marked by significant ecosystem shifts. To understand these past climates and their impacts, scientists turn to nature’s own archives — ice cores, tree rings, sediment layers and fossils — which preserve a record of Earth’s environmental history.
These past warm periods provide valuable insights into how our planet has responded to climate warming in the past and how it may adapt to future changes.
Sediments gradually accumulate over time, forming distinct layers composed of organic matter, plant remains, pollen, microorganisms and chemical compounds. These deposits build up in lakes, oceans, caves, rivers, peat bogs and even frozen permafrost. As natural archives, they preserve valuable clues about past climates and ecosystems, helping scientists piece together Earth’s history. Dating methods allow researchers to trace this history, and now, with the ability to decode ancient DNA we have a powerful new tool to reconstruct past ecosystems, from vegetation to fauna and microbiota.
Ancient DNA is the genetic material that living organisms leave behind in the environment after they die, preserved in sediments, soil and ice for thousands and millions of years. By analysing it, we can uncover past environments and the life they once held, revealing how climate has shaped them over time.
At TOLERATE, we study soil microbes that help plants grow and withstand stress, key to their adaptation to heat and drought. These adaptations are crucial for sustaining biodiversity, healthy ecosystems and food security in a warming world — an important challenge for scientists developing climate-resistant plants. Using ancient DNA, we identify the plants and microbes that thrived in past warm climates and explore the genetic adaptations that allowed them to survive. These adaptations — such as heat-resistant proteins, deeper root systems for accessing water, or symbiotic relationships with beneficial microbes — offer valuable insights into how life has already responded to climate change.
By studying these natural strategies, we can develop innovative soil-based solutions to enhance crop resilience to extreme temperatures, drought and environmental stresses, using insights from the past to create future-proof strategies for sustainable agriculture and global food security. In other words,
We explore the past as a natural laboratory for future solutions
Amedea Perfumo
Alfred Wegener Institute (AWI)
Helmholtz Centre for Polar and Marine Research for Polar and Marine Research