Some animals catch cancer from others in their species – here’s why humans aren’t one of them

Bullhead catfish. jack perks/Shutterstock.com Scientists in Vermont have just discovered something that shouldn’t really be possible: a skin cancer that’s spreading from catfish to catfish. It’s only the fourth transmissible cancer ever found in nature. Catfish now join Tasmanian devils, dogs and shellfish as the only animals known to carry naturally occurring cancers that can pass between individuals. In each case, cancer cells break free from one body, travel to another and carry on living…