Modern antibiotics have been saving lives since Alexander Fleming discovered penicillin in the 1920s. But bacteria are living, evolving organisms, and they have a tendency to figure out ways to survive—so much so that antibiotic resistance is a major threat to public health. The Centers for Disease Control and Prevention (CDC) estimates that 23,000 deaths a year result from drug-resistant bacteria [PDF]. As antibiotics become less effective, scientists are looking to new methods of treatment to combat infections, like fecal transplants for Clostridium difficile infections. Now, a group of researchers is looking to crocodiles. 

Alligators and crocodiles have surprisingly robust immune systems, and research has indicated that their blood contains strong pathogen-fighting properties, even against species found to be antibiotic-resistant. With the help of crowdfunding, Evon Hekkala, a Fordham University and American Museum of Natural History genetics researcher, is trying to analyze crocodile genes to figure out what exactly makes crocs so healthy. Using museum specimens and living animals, she and her graduate student colleague Taylor Hains have collected samples of DNA from 18 crocodile species and six crocodile relatives. 

Humans develop immune responses to pathogens they’ve already been exposed to (which is why most people don’t get chicken pox more than once), but crocodilian species have immunities to microorganisms they’ve never encountered before. Figuring out how exactly crocodile genes code for this level of protection could help researchers figure out how to harness similar abilities in human medicine.