Or, for a medical example, suppose smoking multiplies the risk of lung cancer by some number R: then the Wald test can be used to test whether R = 1 (i.e. there is no effect of smoking) or is greater (or less) than 1 (i.e. smoking alters risk).
There are more than 900 species of Tardigrade or Water Bear, pictured. They're found everywhere in the world, from the highest mountains to the deepest oceans. Boil the 1mm creatures, freeze them, dry them, expose them to radiation and they're so resilient they'll still be alive 200 years later.
Brown bears are the undisputed monarchs of the open tundra and mountains of Alaska. On the Arctic Refuge, they live farther north than any others of their species. Also called grizzlies because of the grizzled blond tips of their fur, brown bears can be shades of cream, brown, or black. Brown bears escape the Refuge's long winters by hibernating for up to eight months each year. During this long sleep, bears do not eat or drink. They do, however, give birth and nurse their cubs. Outside the den, brown bears explore widely for foods that are often in short supply. While spring snows remain, bears eat carrion, ground squirrels, and roots.