Detection of gene mixing in Central American river turtles

Scientists working at the Center for Evolutionary Genetics and Conservation, Smithsonian Biological Conservation Institute, USA and colleagues have discovered a blend in genetic structure from collected tissue samples. collected from 238 wild turtles at 15 different locations (in southern Mexico, Belize and Guatemala).

The results of this study were published in the Journal of Genetic Conservation.

The Central American river turtle ( Dermatemys mawii ) is an omnivore, living underwater, representing populations of turtles from three geographically different river basins, isolated by significant distances and high mountain ranges. .

Central American turtles (Dermatemys mawii) are at risk
highest extinction in Central America.

" We hope to find different genotypes in each basin ," said Gracia González-Porter, the lead author of the study, working at the Center for Evolutionary Genetics and Conservation, at Smithsonian Biological Conservation Institute, USA. " Instead, we see a mix of breeds everywhere ." Although geographically isolated, genetic data show that different turtle populations have been in close contact for many years.

"How did this happen? " The researchers wondered.

The best explanation possible, according to González-Porter and his colleagues, that many centuries ago brought turtles together. Turtles have been used as food, commercially and in millennia ceremonies, they are transported far away and stored in ponds and lakes to feed gradually. Some turtles have escaped into the natural environment and come together.

" For centuries, this turtle is in the Mayan daily menu and other indigenous people, who live within the historical distribution of this Central American Turtle, " the scientists pointed out. out in their report. " The Central American river turtle is a very important source of animal protein in the ancient Mayan people, in the days of the Petén (Preclassic in the period 800-400 BC). And it is possible that this Central American river turtle is also in The daily menu of the people in Olmec culture more than 3,000 years ago . "

A sample of Central American turtles was found in the ancient Teotihuacan cemetery in Mexico, a point far from the turtle's known habitat range of more than 186 miles , the researchers said. An ancient sculpture of the Central American turtle at the Mexico City National Museum of Anthropology was found in Mexico's river basin, far from the turtle's habitat range of more than 217 miles.

" Central American river turtles are inherently bold and persistent ," González-Porter explained, "their own shell class, which protected them during transport. People released turtles into their ponds to eat meat slowly and they escape to the natural environment . "

During the rainy season in the tropics, the currents are very large, González-Porter said. Floods in rivers and lakes, make captive turtles escape and mix with local turtles.

This way of transporting and storing these ancient turtles continues to this day. In Guatemala, Central American river turtles are kept in cost-effective ponds, where they can easily be caught again when needed. Similarly, in Tabasco state, Mexico, turtles are also kept in simple ponds, until they are consumed or sold out.

Genetic analysis of Central American river turtles has been initiated, because they are facing a very high risk of extinction.

They are the last survivors of the giant river turtle of the family Dermatemydidae.Trung My river turtle is the most endangered turtle in Central America . Recently, an increase in commercial demand for turtle meat has pushed them to the brink of extinction (every 0.99 kg of meat from the Central American river turtle is worth $ 100). Most of the Central American river turtles have disappeared in the natural environment and these turtles are now mostly in remote areas, where people are difficult to access.