How did giraffes end up with a long neck?

Through evolution. The whole theory of evolution was first based on the giraffe's neck. Darwin say the giraffe, and asked himself the same you just asked me. He realized that all of the food that the giraffe ate came from high up in the trees. So from that observation, he inferred that the giraffes needed long necks to survive. I repeat: They NEED long necks to survive. That is the whole theory of evolution. Let us pretend it is a long time ago, and at this time giraffes have short necks. This is a problem, as the food on the ground is running out and they need a way to reach the food in the trees to survive. Out of the whole herd of giraffe, though, two of them (lets call them Gina and Patrick) were somehow born with slightly longer necks. As Gina and Patrick were the only ones in the herd who could reach the food, the rest of the giraffes died and they survived. They mated, and Gina gave birth to Donna, Hugh, and Theodore. Once Donna, Hugh, and Theodore grow up, their parents die. Hugh and Patrick and Donna all have inherited their parents genes for long necks, so they are as tall as them--except Hugh, because he is taller. Donna and Theodore can reach their food, but as the best and ripest food is at the very top of the tree, only Hugh can reach that. So Hugh grows big and strong, AND he has an EXTRA tall neck, so the females are attracted to him. So HE is the one who gets a mate,and passes on his tall-neck genes onto his children. Get it? --Answerguy555
Giraffes got their long necks by natural selection. Because their food was high in the trees, natural selection lengthened the neck of the giraffe. A giraffe's long neck contains only seven vertebrae, like a human's neck. Giraffes not only use their necks to stretch high into the trees, they also use them to graze on the ground. Males often use their necks to fight one another during the mating season when there's a female to defend. No wonder why giraffes have long necks.
a giraffe has to have a long neck because of what it eats. it eats leaves! the leaves are on the tree so it needs a long neck to get the leaves because it can not climb the tree.