Eels should be chewed before eating, otherwise they will swim out of the stomach | Natural Trumpet

Two-color lobster

What? There are lobsters that grow like this! ?

Ding ding ding! | Robert F. Bukaty / AP

Recently, researchers discovered a bicolor lobster in a marine science laboratory in the United States. Wild lobsters are usually dark brown and turn orange-red when cooked, but this lobster has a magical yin-yang color, making it the coolest of all lobsters.

This bicolor lobster was born from the fusion of two eggs, a rare phenomenon with a probability of only one in 50 million . Researchers speculate that the lobster may have a genetic mutation, which caused the protein bound to the shell pigment to change, turning half of the shell into a bright orange-red color.

SSR in lobsters: Light blue lobster | Robert F. Bukaty / AP

Every year, hundreds of millions of lobsters are caught from the sea, and fishermen will find some strange-looking lobsters among them, such as orange-red lobsters, or even rarer, cotton candy-like light blue lobsters, the latter of which have a probability of only one in 100 million (but it is said that the taste is no different from ordinary lobsters).

The researchers who discovered the bicolored lobsters specialize in collecting and raising these rare-colored lobsters. They want to study how these rare colors come about.

This lab also raises rare spotted lobsters | Robert F. Bukaty / AP

Flying Spaghetti Monster

A flying spaghetti monster appeared under the sea!

Flying Spaghetti Monster! | National Oceanographic Centre / SERPENT Project

During a recent underwater exploration, researchers discovered a mysterious "flying spaghetti monster" more than 600 meters underwater near Chile. It has noodle-like arms with pink tips and wisps of appendages floating around it, like a large mass of tangled spaghetti.

In fact, this is a rare marine creature belonging to the order of siphonophores , and its scientific name is Bathyphysa conifera. In our eyes, it looks like a single individual, but like other siphonophores, it is actually a large group of individuals gathered together to form a colony . Each member is responsible for a part of the life function, and together they maintain the survival of the colony. Each individual cannot survive alone.

During the deep-sea exploration in 2015, someone also photographed the "Flying Spaghetti Monster" | National Oceanographic Centre / SERPENT Project

The "Flying Spaghetti Monster" was just one of the discoveries during this underwater exploration. The researchers also discovered the Casper octopus for the first time in the South Pacific. This is a new species discovered in 2016, but because no one has collected its samples, it has not been officially described and named.

The translucent Casper octopus is very round and cute | ROV SuBastian / Schmidt Ocean Institute

The expedition also captured the first live Promachoteuthis squid. Based on specimens collected in the 19th century, researchers identified three species of this genus, but people had only seen dead individuals in fishing nets. This is the first time they have been photographed alive.

First photo of a living squid of the genus Promachoteuthis | ROV SuBastian / Schmidt Ocean Institute

Know yourself before you fight

Even if you are a fish, you have to look in the mirror and weigh your own weight before fighting.

A cleaver looking at itself in a mirror | Osaka Metropolitan University

In a new study, researchers showed a group of wrasses pictures of their own kind, and they all showed aggression in response to the pictures. Then, the researchers installed a mirror on half of the fish, and the other half did not. A week later, the researchers showed all the fish new pictures of their own kind again. The results showed that if the fish that had looked in the mirror found that their own kind was larger than themselves, they would be less likely to attack ; while the fish that had not looked in the mirror were still fearless, and would attack without saying a word, no matter how big the other party was.

In the wild, although the cleaver fish do not have mirrors, they will first weigh the possibility of defeating the opponent - they will first swim parallel to the opponent fish , compare their own size with that of the opponent, and then decide whether to fight or run.

Two cleaverfish swimming together | Bernard DUPONT / Wikimedia Commons

Before this, the mirror test used by scientists to study animal self-awareness usually involves marking the animals and then observing whether they realize that they have an extra mark on their bodies when looking in the mirror and try to remove it. However, some animals may recognize themselves in the mirror but are too lazy to remove the mark, so these animals are mistakenly considered to have no self-awareness.

This test takes advantage of the nature of cleavers and cleverly combines the mirror test with their natural behavior . The experiment proved that cleavers can not only recognize themselves in the mirror, but also use the mirror to evaluate their own image and measure their chances of winning in a fight, which reflects a deeper level of "self-awareness".

Killer whale hunt failed

Disturbed by human noise, killer whales can't catch fish!

Recently, researchers analyzed information from trackers and recordings recorded between 2009 and 2014. The data was collected from Southern Resident killer whales and Northern Resident killer whales, which are killer whale ecotypes that mainly prey on salmon. The Southern Resident killer whales currently number just over 70.

A northern resident killer whale wearing a tracker called a Dtag, which includes two underwater microphones, pressure and temperature sensors, a three-axis accelerometer and a magnetometer | Brianna / NOAA

The results showed that the killer whales' hunting success rate was related to ship noise . Of the 95 recorded killer whale hunting events, most occurred in low or medium noise environments; six occurred when the ship noise was particularly loud, and only one of them successfully caught a fish.

The hunting process of killer whales includes searching, chasing and finally capturing, and the noise of ships will affect each step . Killer whales first find prey through echolocation and determine their type, size and location, and then initiate the pursuit. The sound of ships, especially the noise generated by propellers, makes the underwater noisy, interfering with the killer whales' ability to identify echoes, thereby reducing their success rate in capturing prey.

Killer whales use echocalls to locate and track salmon | Uko Gorter / Wikimedia Commons

Researchers believe that this also explains why the southern killer whale population has been slow to recover - their favorite food, salmon, is now difficult to catch, making it difficult for female killer whales to get enough nutrition , which may lead to their high pregnancy failure rate.

How can we make the waters where killer whales live quieter? The most practical way is to reduce the speed of ships to reduce propeller noise. Both the United States and Canada have launched ship speed reduction programs in the hope that killer whales can eat normally. However, the destruction of salmon habitats and marine pollution still silently and invisibly affect the survival of killer whales.

Save the jaguar

Veterinarians at a big cat sanctuary in Brazil rescued a jaguar with burns on all four of its paws from wildfires.

Wounded Paw | References [5]

Its home is the Pantanal wetland, the world's largest wetland, very close to the Amazon rainforest. Due to climate change, a huge drought has occurred in the area, which has led to wildfires. In September alone, 1,452 fires have been recorded in the Pantanal . Countless wild animals have been injured in the fires, and this jaguar is one of the victims.

Jaguar Itapira is treated under anesthesia | References [5]

It is a female jaguar about 2 years old, weighing 57 kilograms, named Itapira. Before receiving treatment, it was injected with anesthetic darts, and several veterinarians helped it clean the wound, wrapped its paws, and used disinfecting ozone.

In the wild, if a jaguar's paws are burned, their hunting ability will be greatly affected. Fortunately, Itapira was found and treated in time, and there is hope that he will eventually recover and return to the wild.

Jaguars in the wild can hunt crocodiles and capybaras | Gustavo Gaspari / Wikimedia Commons

But another jaguar was not so lucky. In 2020, another female jaguar also suffered burns on her paws in the fires in the Pantanal. But she also lost the tendons used to control her paws, and her injuries were more serious than those of Itapira, and she would not survive even if she was released into the wild. This jaguar was therefore kept in captivity, and she gave birth to two cubs in captivity, one of which will hopefully be returned to the wild.

Eel Escape

After being eaten, Japanese eel larvae can actually escape from the gills of their predators!

X-ray of an eel moving through the digestive tract of a predator | References [6]

To study how eels successfully escape, in a new study, researchers injected eel larvae with barium sulfate, a contrast agent, and then placed the eels and their predator, the dusky sand tang, in the same fish tank. Not long after, the eels were swallowed whole by the predator, and using X-ray technology, the researchers observed the eels' movements in the predator's digestive tract .

Of the 32 eels swallowed by predators, 9 managed to escape, but they did not swim out of the mouth, but squeezed out of the gills . At first, they would wriggle along the stomach wall, trying to find a way out. After groping and feeling, they would insert the tip of their tail into the esophagus and gills, twisting and turning until they got out of the slit of the gills and regained their freedom.

Predator: Just because I swallow my food without chewing it? | KENPEI / Wikimedia Commons

Because eels are small and slippery, they do not cause permanent damage to predators when they get out of their gills. After the eels escape, the predators are still alive and well. Researchers believe that in the wild, when faced with the threat of predation, eel escape should be more common. The next step is to study the muscles and body structure of eels to see what characteristics give them super escape ability.

References

[1] https://phys.org/news/2024-09-rare-lobster-scientists-shell.html

[2] https://schmidtocean.org/new-seamount-and-previously-unknown-species-discovered-in-high-priority-area-for-international-marine-protection/

[3] https://www.nature.com/articles/s41598-024-70138-7

[4] https://onlinelibrary.wiley.com/doi/10.1111/gcb.17490

[5] https://phys.org/news/2024-09-brazil-vets-jaguar-pantanal.html

[6] https://www.cell.com/current-biology/fulltext/S0960-9822(24)00926-6

Author: Cat Tun

Editor: Mai Mai