Listen to the frog's voice or sing it out, Chlamydia has caused the extinction of 90 species of amphibians in the world

Home > Explore

Listen to the frog's voice or sing it out, Chlamydia has caused the extinction of 90 species of amphibians in the world

2019-04-07 08:03:43 163 ℃

_Beautiful Pristamantis living in Panamanian streams belong to the frog

Panamanian forest was once an amphibian park. In the evening, dozens of frogs chorus in chorus, quite a trace of "rice flowers in the fragrance of abundant years, listen to the sound of frogs" full of poetic. In just a few years, however, everything has changed. Amphibian chorus became weaker and weaker, forests became quieter and many amphibian species began to disappear. A team of international researchers led by Australian National University (ANU) has found that over the past 50 years, a fungal disease, chlamydia, has led to a sharp decline in the population of more than 500 amphibians, 90 of which have been extinct.

Amphibians can live either in water or on land, mainly composed of frogs, toads and salamanders. Where did the mass extinction of amphibians begin? What is the "evil" of chlamydia? Can we reverse the extinction of amphibians? Where have all the frogs gone? The story of

should start in the 1970s or so. Dr. Liu Xuan, an associate researcher at the Institute of Zoology, Chinese Academy of Sciences, told Sci-tech Daily: "There is abundant evidence that amphibians have been experiencing global population decline and extinction since the 1970s, with a rapid decline and a wide range of threatened species, ranking first among terrestrial vertebrate groups. Relevant scholars regard the rapid decline of amphibians as the landmark event of the sixth mass extinction of species in the history of the earth.

Liu Xuan explained, but strangely enough, scientists have not been able to find the reason for the rapid decline of amphibians for a long time. Because many amphibians disappear suddenly in remote mountainous areas or nature reserves far from human disturbance, some mainstream hypotheses explaining wildlife endangerment, such as habitat loss, human killing, climate change and so on, can not explain a large number of amphibian decline events. Therefore, the decline of amphibians was once called a "mysterious decline".

_lemur leaf frog

horrible Chlamydia completely destroyed them

1989. At the First World Congress on Amphibian and Reptiliology held at Kent University, UK, the phenomenon of global amphibian decline began to attract the attention of experts attending the conference. Scientists began to search for the causes of the extinction of amphibians.

According to Liu Xuan, it was not until the late 1990s that a team led by Dr. Lee Berger of James Cook University in Australia discovered a lethal fungus, chlamydia, on the skin surface of a large number of dead and diseased frogs collected from the mountains of southeastern Australia, the mountains of South-Central Costa Rica and the Fortuna Forest Reserve in western Panama. A new window has been opened to explore the mystery of the decline of amphibians. After

, this disease has been reported in South America, North America, Central America, Europe, Africa and Asia, and is presumed to be closely related to the decline of amphibians. In 2013, Dr. Mattel of Ghent University, Belgium, discovered a sister species of chlamydia from the descending population of firebugs in Northwest Europe. After continuous research, scientists found that Chlamydia distributed in different parts of the world with different toxic strains. Since then, the "evil" of Chlamydia has appeared in its original form.

Dr. Ben Scheler, principal researcher in the latest research and of the Finner School of Environment and Society, Australian National University, wrote in the Journal Science that "chlamydia is an amphibian disease caused by Chlamydia fungi. This fungus is very active in wet environments such as streams and rainforests. This skin infectious disease, chlamydia, completely destroys some species and causes sporadic deaths of more species.

Liu Xuan explained that the main lethal mechanism of chlamydia was that the electrolyte exchange function of the skin of diseased frogs could be reduced to less than 50% of the normal level. At the same time, the concentration of blood potassium and blood sodium in diseased frogs decreased dramatically. The imbalance of sodium and potassium metabolism would further affect vasodilation and contraction, which would slow down blood flow and cause serious disturbance of blood circulation, and ultimately lead to sudden cardiac arrest in frogs.

At present, scientists have found cases of Chlamydia in more than 60 countries, of which Australia, Central America and South America are the most affected areas. The unprecedented decline in amphibian species has made Chlamydia fungi one of the most destructive invasive species in the world. Dr.

Scheler said: "The highly lethal wildlife disease, chlamydia, is contributing to the sixth mass extinction of the Earth's species. The disease has led to massive extinction of amphibians around the world, and we have lost some very amazing species. For example, over 40 species of frogs in Australia have declined in number over the past 30 years due to this fungal disease, seven of which have become extinct.

The team's research shows that many species are still at high risk of extinction from Chlamydia in the next 10 to 20 years due to the continued decline in population.

Globalization or "the culprit"

Dr. Scheler explained in the Journal Science that "the wildlife trade driven by globalization is the main cause of the outbreak of Chlamydia in various parts of the world. At present, human beings are moving animals and plants around the world at a faster and faster speed, introducing pathogens into new areas.

Liu Xuan told reporters that the invasion of exotic amphibians and climate change are important reasons for the rapid spread and widespread outbreak of amphibian chlamydia. As a global invasive species, bullfrog can infect amphibians with pot fungi wherever it goes. At the same time, climate change may change habitats that are not suitable for chlamydia, thus promoting the outbreak of chlamydia. It is reported that Liu Xuan and his colleagues have done a comprehensive study on a global scale, and found that international trade in living animals, invasion of exotic amphibians and climate suitability play an important independent role in explaining the global invasive pattern of chlamydia. This conclusion has been confirmed in regional studies in different countries around the world.

Scheler said: "It's very difficult to remove chlamydia from an ecosystem - if it's in an ecosystem, unfortunately, it's there. Part of the reason is that some species that have not been killed by the disease are resistant to Chlamydia fungi, which means that they carry fungi and act as a reservoir, so fungi in the environment continue to flow. What can we do to slow down the extinction rate of amphibians caused by chlamydia? < p > < p > Scheler said there was an urgent need to improve biosafety and wildlife trade controls to prevent more amphibian extinctions around the world.

Liu Xuan said regrettably: "At present, there is no effective method to cure or alleviate amphibian chlamydia. Therefore, on the one hand, the international trade of living amphibians and the introduction of invasive amphibians need to be more strictly monitored in the future, so as to reduce the spread and spread of lethal Chlamydia strains all over the world; on the other hand, the field monitoring of declining amphibian populations should be strengthened, and new technical means should be actively tried and developed to carry out research on the treatment of chlamydia.

Scheler said: "Knowing which species are at risk can help develop future research plans to develop conservation actions to prevent extinction." In traditional Chinese culture, frogs symbolize the vitality of nature and the leisure and tranquility of people's life: "Family rain in yellow plum season, frogs everywhere in grass ponds." We look forward to the joint efforts of the government, scientists and all parties, so that "listening to the voice of frogs" can no longer become a masterpiece. This is not only to restore the richness and diversity of the ecosystem, but also to give people a poetic life.