The Mexican cavefish has hepatic insulin resistance due to an insulin receptor mutation, important for survival in starvation environments.

“these little fish they live inside caves they spend most of their life starving the only time they are able to eat is when something smaller than them swims in front of the cave and then they can reach out and grab it and pull it back into the cave and gobble it up and these workers who studied this mexican cave fish found this cavefish had a mutation in the insulin receptor had profound hepatic insulin resistance and they also went on to say this was important to allow them to survive”