kkleiner writes "Scientists created a group of mice that were incapable of feeling cold by killing off the neurons in the body whose specific job it is to transmit cold sensation from the skin to the brain. Rather than an attempt to create an X-men-like mutation, the study sheds light on how the nervous system transmits sensory information from the body to the brain and may help to develop more sophisticated pain medicines. The study was published in the February 13 issue of the Journal of Neuroscience — led by David McKemy, associate professor of neurobiology at the University of Southern California Dornsife College of Letters, Arts and Sciences." Link to Original Source
I've never been canoeing before, but I imagine there must be just a few
simple heuristics you have to remember...
Yes, don't fall out, and don't hit rocks.