Can you tell a salmon from a sunfish, or northern pike from a rainbow trout with just a single glance? Know which fish have "whiskers," eel-like bodies, or change color during spawning season? If you think you're an expert of all things angling, prove it by acing this quiz!
Around 71 percent of the planet is covered by water, but more than 96 percent of that is made up of salt water in the form of oceans. That leaves just 3 percent of the world's water supply in the form of fresh water, which may consist of rivers, streams, lakes or even glaciers.
While there are an estimated 30,000-plus different species of fish on Earth, more than 40 percent dwell in that slim volume of fresh water, with the remaining 50-plus percent hunkering down in seas and oceans. Of course, these freshwater-dwelling fish have some unique physiological traits that allow them to live where they do. Not only do they have specialized kidneys, with gills designed to filter salt and gasses, but even their scales are different -- making it easier for them to moderate water diffusion through their skin.
With so many freshwater fish to be found, it can be difficult to tell one species from another. Think you've got what it takes? Take this quiz to find out!
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