Evolution Of Sea Turtle Essay

Sea Turtles and Evolution

Human activity is endangering a vast array of lifeforms that have inhabited the Earth for millions of years. Recently I visited the Field Museum in Chicago Illinois to tour an exhibit titled The Evolving Planet. The story that the exhibit told was that of life on planet Earth, and how throughout time Earth has reinvented itself using whatever surviving species that remained after its latest mass extinction period had ended. It depicted in a graphic format how time and catastrophes have forever changed Earth’s landscape, including its inhabitants. One of the inhabitants that has managed to survive and evolve is the sea turtle. I found this ancient reptile very intriguing. The sea turtle is a great example of how evolution transforms species to better adapt to the environment.

Sea turtles have been swimming in our oceans for over 100 million years. Evidence of sea turtles with large teeth, webbed feet and a spike covered neck referred to as Proganochelys were present during the Triassic period. The next species of sea turtle, Santanachelys, inhabited the Earth during the Early Cretaceous period. In the Late Cretaceous period the turtle’s toes elongated and as time passed the webbed feet and toes evolved into flippers. As the period progressed, sea-turtle diversity exploded. The largest of the sea turtles grew to a width of 13 feet and 19 feet in length. There are two families of sea turtles that exist today, which date back to the Late Cretaceous period. The Dermochelyidae family which consist of only one species, the leatherback turtle, and the Cheloniidae family, which is made up of two subfamilies that include the Green turtles, Flatback turtles, Hawksbill turtles, Loggerhead, Olive Ridley, and Kemp’s Ridley