What are the causes of hatching sea turtles becoming female only?

ByDeeje

There is a report that the proportion of females is increasing compared to males in the latest survey on sea turtles. This trend will be strengthened in the future and it is expected that it will have a big influence on the survival of sea turtles.

Effects of rising temperature on the viability of an important sea turtle rookery: Nature Climate Change: Nature Publishing Group
http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2236.html

Climate Change Is Turning All Sea Turtles Female | VICE United States
http://www.vice.com/read/climate-change-will-make-all-sea-turtles-female

It was published in science journal NaturepaperIt is reported that the proportion of females is increasing in sea turtles that are born. Researchers in the Atlantic Ocean where sea turtles breedRepublic of Cape VerdeSurvey of sea turtles to be changed from eggs on the islands of the islands confirmed that most of the sea turtles hatched at any beach were females and 93.46% of the total was females in the most biased proportion of male and female Thing.

According to a research study, in recent years it has been confirmed that the number of sea turtle populations themselves is on an increasing trend, but if the condition that the proportion of females born this way overwhelmingly exceeds the proportion of males continues , The number of sea turtle populations will begin to decline about 30 years later and it is thought that a crisis situation may be reached 100 years later.

ByUccs biology

It is presumed that global warming is the cause of "Why are only female sea turtles being born?" Sex is determined by sex chromosomes like human beingsHereditary determination (GSD)Unlike the creatures, the tortoise isGender is determined by environmental temperature at hatchingTemperature Dependence Determination (TSD)It is calledSex determinationIt is said that there is a property that the proportion of females increases as the temperature of the outside world rises when hatching. Mr. Ka 84.2 degrees (about 29 degrees C) is a branch line where male and female are born at 50:50, and it is said that the proportion of females will increase as the temperature rises higher than that. In other words, as the temperature of the sandy beach rises due to global warming in recent years, the proportion of the female sea turtle being born is increasing.

ByU.S. Fish and Wildlife Service Southeast Region

As to the reason why the sex determination of sea turtles such as sea turtles is TSD, there are various opinions such as avoiding inbreeding in order to keep the balance of the whole species proper, but it has not yet been elucidated. However, if sea turtles surviving in the process of long evolution have continued to rise in temperature in the future, it will be the situation that "only females will be born", and it is concerned that they may be extinct in the blink of an eye.