The movement of the hard drive's read/write heads over different areas of the disk when accessing fragmented files is slower, compared to accessing the entire contents of a non-fragmented file sequentially without moving the read/write heads to seek other fragments.
The dorsal fins are small and at the base of the tail. The largest mantas can reach 1,350 kg (2,980 lb). In both species the width is approximately 2.2 times the length of the body; M. birostris reaches at least 7 m (23 ft) in width while M. alfredi reaches about 5.5 m (18 ft).
Introduction to Giant Manta Ray. As you can guess from the name, the Giant Manta Ray is considerably large in size. They are dark in color so that they blend in well with their surroundings. They also feature a variety of colorations on the belly that helps to differentiate them from each other.