![]() ![]() This is justified by the age of the fossil of the sea turtle Desmatochelys, which proves that the split of the leatherback turtle relatives from the other sea turtles happened at least 120 million years ago.īut the history of sea turtles goes back much further. This is currently (2022) the current answer to the question “How old are sea turtles?”. If leatherback and hard-shelled sea turtles are considered together, an evaluation of fossil evidence yields an age of the presumed last common ancestor of the two groups, and thus of sea turtles living today, of at least 120 million years ago (Early Cretaceous). If one excludes the leatherback turtles (Dermochelidae), one finds that the last common ancestor of the extant hard-shelled sea turtle species (Cheloniidae) probably lived about 50 million years ago. In addition to methodological issues of principle, this is often due to differing views of what constitutes a “sea turtle”. About the exact geological age of the sea turtles, however, different data are often found. It is a clear that the sea turtles are a conserved group of animals and have changed only comparatively slowly in the course of the earth’s history. The great age of sea turtles is often pointed out and they are often referred to as “dinosaurs of the seas”. However, no group is as consistently adapted to life in water as the sea turtles. Many species are well adapted to life in water, such as the European pond turtle, which is also found in Central Europe, and the North American pond sliders. Other known Cryptodira include land tortoises, soft-shelled tortoises, alligator tortoises, and snapping turtles. ![]() Within turtles, there are the two major groups of side-necked turtles (Pleurodira retraction of the head into the shell by horizontal S-shaped movement) and hidden-necked turtles (Cryptodira retraction of the head by vertical S-shaped movement), with most species, including sea turtles, belonging to the Cryptodira. However, they require air to breathe, and females must return to land to reproduce. As has often occurred with other groups in the evolutionary history of primarily land-dwelling vertebrates, which also include birds and mammals, sea turtles (Chelonioidea) have made a secondary return to life in water. Turtles and tortoises (scientifically: Testudines) belong to the reptiles (Reptilia), a class of cold-blooded vertebrates (Vertebrata) that is basically adapted to life on land. ![]()
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