4. Grizzly Bears

Grizzly bears survive thanks to their sense of smell. Their sensitive sniffers make them a fantastic predator in their natural environment. Grizzly bears can smell humans and other animals as well as danger up to almost 20 miles. Do not be surprised to find out that grizzly bears can also sense approaching storms and other natural disasters. It is reported that their senses are strong enough to sniff out cancerous cells. The only problem is that working with this species might be dangerous in itself. Fortunately, there are other species we can trust this job.