Appearance & Behavior
Birds were the first flying machines. They knew what to do before the Wright brothers built the first airplane. Through the millennia they have evolved to be built for what they need to do. This is reflected in the size and shape of their heads, beaks, wings and legs. This branch of biology is called “morphology,” or the study of living things, their form, and the relationships between their structures. By observing carefully, it’s easy to see that the birds’ bodies evolved to match their behavior and natural environment. Let’s take a closer look.

Interior least terns are elegant, white birds with a black cap and white forehead patch. Terns eat fish, so they have a chisel-like beak for stabbing and catching fish. And because the tern relies heavily on water for feeding, they have webbed feet.

Terns have evolved to be birds of flight. They need to be able to hover, dive, capture fish and fly back to their nests and feed their young. They have long, narrow, elegant wings that allow them to hover, almost like a helicopter.

Terns’ wings are built to travel long distances since they migrate thousands of miles from the Central U.S. to South America where they spend the winter.


Piping plovers have short, stocky bodies with white undersides and a grayish, tan back; they have a single black necklace. While some bird species, such as the cardinal, have different coloring for male and female, the only way to determine the sex of piping plovers is to look closely at their beaks. The males have a distinct vertical line dividing the orange and black color; the females have a feathered or blended division between colors. Because plovers eat insects, the beak is just long enough to probe into wet sand to get bugs and worms.
Piping plovers spend their winters on the U.S. Gulf Coast and southern Atlantic coasts, and because they don’t migrate as far as terns, their wings are a little shorter and more rounded.

Piping plovers like to run. They have adapted to move very quickly, so they have very long, slim legs.
