All the fish in the world

ldquo;What makes a fish a fish?" asks a mudskipper with adorably exaggerated eyes and mouth. "Fish are like me!" answers a trout, but Mudskipper shows Trout that the answer isn't always clear-cut among the 33,000 known species of fish in the world. In beautiful, colorful, and detailed underwater scenes with an impressive multitude of fish varieties, Trout announces typical fish traits, like scales, fins, backbones, and gills, while Mudskipper is ready to point out exceptions. Informational text in a more formal font provides additional and accessible facts and fish examples, such as sturgeon with chain mail--like scales and hagfish with no scales at all. Other scenes reflect even more variety among fish, from color, size, and shape to the way fish sense the environment around them, prepare beds for eggs, and live at different sea levels. In the last scenes, Mudskipper crawls onto land, demonstrating differences in movement and breathing among fish. Finally, the piscine narrators can agree on one thing--fish are amazing in all their forms. A concluding author's note highlights the elusive definition of fish as well as what makes both mudskippers and trout impressive. And what about all those illustrated fish? A five-page key identifies them in this informative and eye-catching picture book.

Mudskipper shows Trout that it's not so easy to say "what makes a fish a fish." There are thousands of ways to be a fish. While most fish have scales, fins, backbones, a streamlined shape, and gills for breathing underwater, there are surprising exceptions. As he did with the kiwi in All the Birds in the World (2020), Opie picks an outlier to be a main character in this introduction to a wide-ranging animal category. Spread by spread, Mudskipper shows Trout ways that fish are alike and different in underwater scenes filled with clearly recognizable fish. (Scene by scene, over 150 species are identified, according to the key in the backmatter). One spread shows fish that differ in shape and color; another, size; a third, different patterns; and a fourth considers scales. Varieties of sharks and rays illustrate the point that some fish skeletons are made of cartilage, not bone. Rotating the book 90 degrees reveals fish that swim in dark sea depths. The author also covers nests, eggs, and live birthing as well as different sensory organs, locomotion, and breathing. Finally readers learn what makes Mudskipper special. "There's never just one way to be a fish," Mudskipper concludes; narrative text clarifies: "Over 33,000 ways, to be a little more precise." There's solid science information in the text, but the story is carried through by conversation between the two named fish. Aquarium visitors will recognize some of the more striking species. A broad and engaging introduction to the largest vertebrate group. (author's notes) (Informational picture book. 5-10) Copyright (c) Kirkus Reviews, used with permission.