Modern humans started spreading from Africa to Europe, Asia, and Australia some 100,000 years ago – a process that took about 70,000 years. We also know that at some point in the past 25,000 years, a group managed to reach America from Siberia at the end of the last ice age.
However, exactly when this occurred and which route these early pioneers took has long been debated. Now new research based on ancient DNA and plant remains from lake deposits, published in Nature, is finally helping us to answer these questions.Lake sediments can help shed light on the plant and animal life of this period because the successive layers of sediment allow us to step back in time to reveal a history of past environments. The researchers recovered sediment cores dating back to almost 13,000 years ago from an area of the corridor which is thought to be the last to become ice-free. Identification of the pollen grains and small fragments of plants in sediments are important in revealing vegetation development.
