Page 164 - Engineering in Nature

Engineering in Nature

ships. However, a great number and variety of creatures live beneath
the sea. They, too, are exposed to pressure and must meet such needs
as food and protection. Yet none of the difficulties that submarines
must contend with constitute a problem for these creatures.

All marine creatures, from the tiniest fish to the largest whale,
move around easily and use their superior maneuvering ability to
swim and feed in the most productive manner. All species of fish have
been designed to swim perfectly. Their fins have been specially lo-
cated, and the shape of their tails, the size of their gills, and the pro-
trusions and cavities in their skins all meet their needs in the best
possible manner.
As you'll see in the pages that follow, the design in these living

God has created fish with a physical form that allows them to move through water with
no difficulty. Their structure, oval at the front and resembling a pointed shuttle at the
back, reduces the friction of the water to a minimum. Some fish, skates for example,
possess a different shape that's equally ideal for moving through water.

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