Female or male? In turtles, sex is determined by temperature
Summary:
The sex of turtles–which is difficult to identify by their anatomy and is usually discovered by blood tests and DNA samples–is determined by the temperature at which the egg laying medium is found.
This happens because a colder incubation temperature of the egg directly affects a gene that acts exclusively on the immature sexual organs of the turtle and, in turn, acts as a "biological switch", activating other genes that allow the testicles to develop. (As it is shown in the picture)
In contrast, when the temperature is higher, this gene is not activated and the male reproductive organs do not develop, resulting in a female.
The current rate of temperature increase is 0.17°C per decade, which is expected to increase the global temperature by a total of 1.5°C by 2040.
The aim is to convey that, due to global warming, more females than males tend to be born today, which could endanger some species, especially sea turtles, which are already in a delicate state of conservation.
Link:
Publication date:
12/05/18
Scientific field:
Biology.
Glossary:
Gene: a distinct sequence of nucleotides forming part of a chromosome, the order of which determines the order of monomers in a polypeptide or nucleic acid molecule which a cell (or virus) may synthesize.
Global Warming: a gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants.
Lizard: a reptile that typically has a long body and tail, four legs, movable eyelids, and a rough, scaly, or spiny skin.
Global Warming: a gradual increase in the overall temperature of the earth's atmosphere generally attributed to the greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants.
Lizard: a reptile that typically has a long body and tail, four legs, movable eyelids, and a rough, scaly, or spiny skin.
Analysis comment:
This article explains the critical situation in which turtles find themselves due to climate change, as this causes an increase in the temperature of their environment and this causes more females to be born than males. Consequently, the reproduction of these animals is not carried out as it should and endangers the species.
According to what I have read, studies have been carried out on Raine Island (Australia), the largest and most important Pacific green turtle nursery, which has determined that female turtles outnumber male turtles by 116 to 1. Raine appears to have produced almost exclusively females for at least 20 years.
It is said that, since sea turtles tend to mate with more than one female and males tend to mate more frequently, it is beneficial to have a slight inclination in favor of females, approximately 1 male for every 3 females. However, the figures are extremely exaggerated.
In my opinion, people are (within the insufficient) aware of global warming, i.e. the consequences of pollutants and the degradation of the planet, such as high temperatures or rising sea levels. However, very few are aware of what we are doing to animals, not only because of the pollution of their habitats and the complication of their standard of living, but also because of the extinction of entire species. And we don't just talk about turtles anymore because, like them, incubation temperature also determines the sex of other reptiles, including lizards and caimans, so that means that we could be causing, without even realizing it (the excessive birth of females in Raine has occurred for 20 years and nobody had noticed it), the extinction of many species, little by little.
This article explains the critical situation in which turtles find themselves due to climate change, as this causes an increase in the temperature of their environment and this causes more females to be born than males. Consequently, the reproduction of these animals is not carried out as it should and endangers the species.According to what I have read, studies have been carried out on Raine Island (Australia), the largest and most important Pacific green turtle nursery, which has determined that female turtles outnumber male turtles by 116 to 1. Raine appears to have produced almost exclusively females for at least 20 years.
It is said that, since sea turtles tend to mate with more than one female and males tend to mate more frequently, it is beneficial to have a slight inclination in favor of females, approximately 1 male for every 3 females. However, the figures are extremely exaggerated.
In my opinion, people are (within the insufficient) aware of global warming, i.e. the consequences of pollutants and the degradation of the planet, such as high temperatures or rising sea levels. However, very few are aware of what we are doing to animals, not only because of the pollution of their habitats and the complication of their standard of living, but also because of the extinction of entire species. And we don't just talk about turtles anymore because, like them, incubation temperature also determines the sex of other reptiles, including lizards and caimans, so that means that we could be causing, without even realizing it (the excessive birth of females in Raine has occurred for 20 years and nobody had noticed it), the extinction of many species, little by little.
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