00:00Those cute animals you see on the screen are acholots.
00:05They are a type of salamander native to Mexico and are very famous there.
00:10They are in the Mexican peso and in the souvenir shops.
00:13where they share space with El Chavo del Ocho and Frida Kahlo.
00:16But it's not just their cuteness that catches the eye.
00:19Avocados are studied by science for their high regenerative capacity.
00:24They are able to regenerate entire limbs that have been amputated.
00:27and even parts of the brain and heart.
00:30They're like the real-life Wolverine.
00:35Avocados are common in laboratories and with pets.
00:39But in nature, it has become increasingly difficult to find them.
00:43There are only about a thousand left in Mexico.
00:46Acholots are amphibians, a class of animals that has existed for over 300 million years.
00:52There are over 9,000 species in the world.
00:54And the anchovies, I hate to break it to you, aren't the only ones in danger.
00:58According to a study published in the journal Nature, more than 40% of amphibian species
01:04They are threatened with extinction to some degree.
01:07This is nothing new.
01:08In the 1980s, that rate was already 38%.
01:12So, why is this happening?
01:14Well, of course, habitat loss and climate change help explain the problem.
01:20But in the case of amphibians, there's an additional factor.
01:23There is a deadly fungus that has spread around the world since the 20th century and has put hundreds of species at risk.
01:30Stay there, I'll tell you the story in a moment.
01:40There are three main groups of amphibians.
01:43The one belonging to salamanders, the one belonging to caecilians or blind snakes, and the one belonging to anurans, which are frogs, toads, and tree frogs.
01:51If you don't remember the difference between them, don't worry, I'll explain.
01:55Frogs have thicker skin and prefer land.
01:58Frogs prefer ponds, while tree frogs are the ones that climb trees.
02:03Amphibians descend from the sarcopteryx, which is the great ancestor of all tetrapods.
02:09which are the four-limbed vertebrates, like me, you, and the little pony.
02:14Sarcopterygians were aquatic animals.
02:17Some of them had lungs, well-developed fins, and permeable skin that allowed for gas exchange.
02:24This mix of characteristics allowed them to walk and breathe out of water.
02:30It is clear that this conquest of the land did not happen overnight.
02:34It began in the Devonian period, 400 million years ago, and only took hold in the Carboniferous period, about 300 million years ago.
02:42where it is considered the age of amphibians.
02:45Taking a stroll on the surface was a good thing for these animals.
02:49In the water, the competition for food was fierce, and they needed to stay alert to avoid becoming shark food.
02:56Those who ventured outside found a very different scene, without predators and with a buffet of insects at their disposal.
03:04The larger species were more visible prey, and that's how they ended up going extinct.
03:09But the little ones remain and stay with us.
03:12Okay, so what's the first thing that comes to mind when we talk about frogs?
03:16Perhaps it's their life cycle, which is divided into an aquatic phase, with the tadpoles, and a terrestrial phase?
03:23Well, this is actually quite common.
03:26But that's not the defining characteristic of amphibians.
03:29What unites them is the absence of epidermal appendages.
03:33I'll translate.
03:34That's because they have smooth skin, without feathers, fur, or scales.
03:39This enviable skincare routine helped the amphibians get out of the water.
03:43But today, that advantage is their main weakness.
03:49In 1989, the first world congress of herpetology, the field that studies amphibians and reptiles, took place in the United Kingdom.
03:58Right away, dozens of researchers noticed something unusual in their work.
04:03In many parts of the world, amphibians were dying.
04:06Scientists had been tracking this phenomenon in isolation since the 1970s.
04:12But it was from that point on that the problem began to be seen as a global phenomenon.
04:17Ten years later, science finally discovered the culprit behind the massacre.
04:22It was chytridiomycosis, a disease caused by two fungi.
04:26The chytridium, which is known as BD,
04:29And the besal, which is a sister species and only attacks salamanders.
04:33BD and besal are aquatic fungi.
04:36And their reproductive cells have little tails used for locomotion, like a sperm cell.
04:42They can be carried by rain, fog, and of course, by other infected animals.
04:48The chytrid fungus invades amphibians through the skin.
04:51Remember when I said they don't have any protective layer?
04:54Yes, the path is clear for the fungus.
04:57And the damage is extensive.
04:58The fungus disrupts the intake of oxygen and mineral salts.
05:01which leads to heart failure.
05:04Besal is even more aggressive, as it also causes ulcers and lesions.
05:09The chytrid lineage originates from the Korean Peninsula.
05:12There, some species of amphibians were already accustomed to the fungus.
05:16But in the first half of the 20th century,
05:18One variant spread and gave rise to several strains.
05:22Some of them are quite violent.
05:24And then they started infecting species that did not have prior immunity.
05:28Chytrid fungus has already affected more than 500 amphibian species.
05:32And he decimated 90 of them.
05:34But how did it actually spread around the world?
05:36Well, this happened thanks to the increase in the amphibian trade.
05:40mainly for food.
05:42That's right, although it's not the most consumed meat in the world,
05:46Toads, frogs, and other similar dishes are typical preparations in various cultures.
05:50mainly in Asia and in countries like France and Belgium.
05:54It is estimated that the world consumes 3 billion frogs and toads per year.
05:59The problem is that this is a poorly regulated sector.
06:02that exploits already threatened species and puts others at risk.
06:06The United States, for example,
06:08They prefer that the amphibians arrive there still alive.
06:11which increases the risk of disease transmission along the way.
06:14Even a market with more rules, like Europe,
06:17It still suffers from a lack of oversight.
06:19Most of the world's frog production takes place in frog farms, also known as ranariais.
06:25In Brazil, the first one appeared back in 1935.
06:29But production only gained traction in the 80s.
06:32It was during this time that countries with a tradition in frog farming,
06:36Countries like India and Bangladesh have banned the export of the animal.
06:39From then on, other countries took the lead.
06:42and they remain in the lead to this day, as is the case with Indonesia.
06:45Brazil was once the second largest producer in the world.
06:48with 600 frog farms.
06:50Today, production is more modest.
06:52There are 151 farms that, together, produce 400 tons per year.
06:57The most popular frog around here is the American bullfrog.
07:00All producers must be registered with Ibama.
07:03And there are federal government guidelines for sustainable production.
07:07The problem is that there is insufficient oversight.
07:10A study from Unicamp, for example,
07:12The presence of chytrid frogs was detected in all frog farms in Brazil.
07:16The bullfrog is immune to the fungus.
07:17but it can serve as a vector,
07:20since it's quite common for them to escape from farms and go into the wild.
07:26There are regional conservation efforts,
07:29who monitor the disease and train producers.
07:32But a more structured national plan to combat the fungus is still lacking.
07:37Given the many environmental problems we see around us,
07:40It might seem silly to talk about the little frogs.
07:42But you should know that amphibians play a fundamental role in nature.
07:45They are right in the middle of the food chain.
07:48Without it, its predators would have no food.
07:51Oh, and the insect population, of course, would grow absurdly.
07:56In such a scenario, the crops would have to use more pesticides to control the insects.
08:01And the result would be a rise in food prices.
08:04In other words, buying it at the market would be much more expensive.
08:07And it's all because of amphibians.
08:09The chytrid is not invincible.
08:11It can be killed with antifungals, certain types of viruses, and even heat.
08:16It's best to deal with this now, before the situation becomes irreversible.
08:20It's best to deal with it until kördeOM and second.
08:28Mudra.
08:35Mudra.
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08:48Perdram engestra.
08:48Mudra.
08:48Mudra.
08:49Mudra.
08:49Mudra.
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