Scientists are studying hundreds of dogs at the Chernobyl disaster site that have managed to survive in extremely harsh conditions. They hope that examining the animals' genetics will give them insight into how humans can live in the most brutal of environments. They published their initial study on Friday in the journal Science Advances. They say the work sets the stage for future studies that can answer questions such as: What types of genetic changes help dogs and other mammals survive? And what might hurt their survival chances?