Scientists have revised their estimate of the size of the megalodon shark to 80 feet, based on a new study published in Palaeontologia Electronica. Previous estimates had put the shark at around 59-65 feet in length. The study involved examining megalodon fossils and comparing them to other living and extinct shark species. The researchers also found that the megalodon may have resembled a great white shark in appearance, but new research suggests it was more likely slender and streamlined, similar to a lemon shark.