The Creator made giraffes as an animal that can reach up to 10 ft. tall. Their design includes veins in the neck which contract as the head lowers then raises so as to restrict return blood flow. Also their spots are designed to regulate body heat. Each spot has blood vessel around it directing blood flow to smaller vessels. Each spot is unique to each giraffe similar to unique fingerprints to each human.
And God made the beast of the earth after his kind, Genesis 1:25