John Jameen Research Paper

BIRDS

FLYING MACHINES

ONE SPRING DAY IN 1804, WHEN THE GREAT PAINTER AND NATURALIST JOHN JAMES AUDUBON WAS A TEENAGER, HE SPEID A PAIR OF PHOEBES NEAR HIS HOME IN PENNSYLVANIA. THE BIRDS WERE BUILDING A NEST ON A ROCKY LEDGE. LATER, AFTER THE EGGS IN THE NEST HATCHED, AUDUBON WACHETD THE PHOEBES DART THRUGH THE AIRE CATCHING INSECTS TO FEED THE HUNGRY BABIES. THE YOUNG BIRDS GREW FAST AND IN A WEEKS WERE READY TO FLY. THEY SPREAD THIER WINGS, FLAPPED, AND FLEW A SHORT DISTANCE. AUDUBON WAS AMAZED AT HOW QUICKLY THEY BECAME EXPERTS, EVEN THOUGH THEY HAD NEVER FLOWN BEFORE.

ALMOST ALL BIRDS CAN FLY. FLYING HELPS BIRDS FIND FOOD, REACH SAFE PLACES FOR BULDING NEST, ESCAPE FROME PREDATORS ON THE GROUND, AND TRAVEL EASILY OVER LONG DISTANCES. IT HELPS THEM TO SURVIVE.

DESIGNED FOR FLIGHT
LOOK AT A BIRD'S WING FROME THE SIDE. IT HAS A THICK FRONT EDGE AND A DOWNWARD CURVE TOWARD THE BACK. THE DISTANCE OVER THE TOP IS GREATER THAN THE DISTANCE ACROSS THE BOTTOM. WHEN A BIRD MOVES THROUGH THE SKY, THE AIR AT THE FRONT OF THE WING SEPARATE AS IT FLOWS OVER THE WING'S SURFACE. THE AIR TRAVELYNG OVER THE TOP GOES FASTER THAN IT DOES ACROSS THE BOTTOM. THAT'S BECAUSE IT MUST GO A LONGER DISTANCE IN THE IN THE SAME AMOUNT OF TIME. THE DIFFFERENCE IN AIRSPEED CAUSES A DIFFERENCE IN AIR PRESURE. THIS PULLS THE WING AT THE TOP, PUSHES IT FROME BELOW, AND CREATES A FORCE CALLED LIFT. IS WHAT KEEPS A BIRD UP IN THE AIR WHILE IT IS