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.
Northern Water Snake. Description: Northern water snakes are some of the most common water snakes in the country. They can vary greatly in appearance from gray, tan, buff or brown in color. The adults have dark bands and are often mistaken for copperheads or cottonmouths but are not venomous.