Sea turtles' family name is Chelonioidea derived from the Greek word Khelone, meaning tortoise. They are powerful, beautiful, and graceful creatures. They are found in all oceans except for the polar regions with 7 out of the 8 species nesting along the thousands of miles of Mexico's coastline. This is because Mexico has a strong diversity of coastal environments providing ideal conditions for their rest, nutrition, and reproduction. Fossil evidence of sea turtles goes back to the Late Jurassic period 150 million years ago, but the first record dates back to the beginning of the Mezozoic Era a period that began 225 million years ago. When it ended they managed to survive one of the largest extintions of our planet. Sea turtles were actually present at the birth of mammals and human beings.
These exceptional creatures can weigh up to 2000 pounds and reach up to 100 years of age. In ancient Maya the turtle has many symbolic meanings including endurance and longevity from these facts. Overall they had the fundamental role as the origin of life for this culture, being a metaphor for the first emergence of earth from the sea with much significance of it being a creature of two elements, earth & water. The sea turtles shell to the Mayans was seen as the celestial vault and was believed to carry the wisdom of time on its shield because of it containing 13 parts like the 13 moons of the year. To them there was a close relationship with water and constellations and the sea turtle satisfied both. The body was then revered as the axis that united both heaven and earth. There are a number of Maya stone alters that are carved in the form of turtles and the Maya Maize God is represented often rising out of the split earthly turtle shell possibly symbolizing stability. The shell was used in these ancient times as drums making the turtle a prime provider of music. These drums were important as their sound was used to initiate the rumble of thunder and bring rain. It was this rain that brought forth the corn and the corn was life. These people saw the connection even in the turtle and life so much that it's been known to be said by them that when a corn seed starts to sprout, the earth forms a little bulge that resembles a turtle shell from where the stalk will emerge. The sea turtle brings hope.
Sea turtles' bodies are tapered at both ends which means they cannot retract their head and limbs into their shells for protection like their land counterparts, but it means they have extremely streamlined bodies for gracefulness in the water because it reduces friction and drag much like a boat hull. They are so suited for the water that they migrate enormous distances some even crossing entire ocean basins. They are air breathing reptiles that have lungs and regularly surface to breath, but their capabilities of holding their breath are astounding. If they are foraging exerting a lot of energy it can range from 5 minutes to 40. If they are sleeping, they do not have to surface for 4 to 7 hours. This may be the cause of why they often seem so elusive when they have been spotted while cruising, they just pop up for a second to say hi, then back down they go. Over time the sea turtle's limbs have actually evolved from being just for locomotive purposes to actually aiding in feeding being able to hold, swipe, and forage. Some other fascinating attributes about the sea turtles make up are that they are the first biofluorescent reptile found in the wild. This characteristic is usually attributed to a strategy for attracting prey or perhaps a way to communicate. It is likely in the turtle's case a defense or camouflage when hiding at night amongst other fluorescent organisms like corals. These fascinating creatures also maintain an internal environment that is hypotonic to the ocean, meaning they create a ion and water balance much like a de-salination process of a watermaker. They do this by excreting salt ions with a special gland, capable of producing tears with a higher salt concentration than sea water. The sea turtle is wise.
Perhaps the most fascinating quality that sea turtles have is one that is still not fully understood and that is that they possess both an incoordinate magnetic map and a magnetic compass sense. They use a form of navigation called magnetoreception which allows an organism to detect the earth's magnetic field. This guides them in orientation, and they possibly form regional maps in their knowledge. They are able to determine their position relative to a goal with latitude and longitudinal information thus forth maintaining a specific heading. This great knowledge sea turtles possess is a wonderful combination of inherited magnetic info, socially facilitated migration, and geomagnetic imprinting in the species. Although they spend most all their life in the water and mate in the ocean as well, this knowledge is so significant for the main purpose, the purpose of nesting.
Mexico hosts these magnificent creatures for nesting between June and November. This is reserved for the females; males usually do not ever hit land in their life after they are hatched. At the age of 10 to 20 years females will arrive at land for their first time when they return to exactly the beach where they were born themselves. These ladies can be fertilized by several males, and they come ashore 3 to 5 times at intervals of 10 to 15 days in the protection of the night. They, with great determination, come ashore and dig a hole over 20 inches deep and lay anywhere from 50 to 350 eggs being called a clutch. She'll lay 1-8 clutches in a single season. The sea turtle will gently cover this hole back up with sand and camouflage it with vegetation. Sometimes they will even make decoy nests. Then they return to the sea. After about 2 months the hatchlings will hatch and emerge from the sand only being about 2 and a half inches long. Its then that they begin their often perilous journey. There are so many hazards on this journey and first years of their life that only about 1 in 100 of hatchlings will survive. For the first 3 to 5 years of the sea turtle's life they spend most of their time either floating in seaweed mats where they find food, shelter and water, in the tide lines formed by the front of the main currents, or in the passive of the ocean currents. Once they reach adulthood, they move closer to shore to begin the beautiful cycle again. Adult sea turtles have very few predators, mainly large aquatic carnivores like sharks. Humans are actually they only real threat. The sea turtle is steadfast.
The seven different species in Mexico are the Leatherback (Dermochelys Choriacea) the largest who can make a 7,000 mile journey within 10 months. Their carapace unlike a hard shell can compress at depth allowing them to dive deeper than any other marine reptile. the Green (Chelonia Mydas) they got their name because they are green on the inside from a diet consisting primarily of algae, the Black (Chelonia Agassizi) the cousin of the Green both having serrated beaks evolved to eat sea grass, the Hawksbill (Eretmochelys Imbricata) having an exquisite shell pattern and exhibits the most biofluorescence, the Loggerhed (Caretta Caretta) the most widely distributed hard shell that has a larger head than others and powerful jaws to crack open the hard shells of mollusks & crustations, the Olive Ridley (Lepidochelys Olivacea) who show up by the thousands at nesting beaches together during arribadas; nesting events timed around moon cycles, & the Kemp's Ridley (Lepidochelys Kempii) being the smallest and where on the edge of extinction.
Loggerhead turtles, both Ridley turtles, and Hawksbill turtles are omnivorous their entire life. The Green & Black turtles diet changes with age. Juveniles are omnivorous and as they mature, they become exclusively herbivorous. The Leatherback turtles feed mainly on jellyfish, while the Hawksbill turtles principally eat sponges. All of our sea turtle friends, especially the Green, are the few creatures that eat sea grass. The other being manatees. Sea turtles grazing on sea grass beds maintains the health of it needing to be constantly cut short to help it grow across the sea floor. These sea grass beds provide breeding and developmental grounds for numerous animals. Without them the lower levels of the food chain would be lost. Sea turtles also maintain a symbiotic relationship with yellow tang in which the fish eat algae that grows on the turtle's shell.
Unfortunately, sea turtles eat plastic bags that are in the ocean because they confuse them with their actual diet of jellyfish and algae's. This plastic will clog their intestines and cause internal bleeding with an eventual death. The ratio of plankton to plastic in the world's oceans is currently 1 to 6. In Mexico the federal government established many measures geared toward protection, conservation, recuperation, and research of sea turtle populations. The truth is we are a species that can work to preserve other species and all sea turtles are critically threatened or endangered as a species. So, at the risk of sounding cliche lets help "Save The Turtles"
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