This may be the smallest cat in history, living in Anhui | Natural Trumpet

Welcome to the 74th issue of the Nature Trumpet column. In the past half month, we have collected the following natural news and research worth reading:

1) Penguins will also divorce if reproduction fails

2) The squirrel's skull is deformed due to human feeding

3) The smallest cat ever found appeared in China 300,000 years ago

4) Octopuses’ superb control comes from their segmented nerves

5) The red deer entangled in the rope was finally rescued

6) The one-eyed wolf queen ended her legendary life

Penguin Divorce

Penguins are not necessarily lifelong partners, and divorce will eventually take place.

In a new study that lasted 13 years, researchers tracked the marriages of little blue penguins on Phillip Island and recorded which individuals changed partners in the next breeding season. They found that although many penguins maintain a lifetime relationship, if the penguin couple fails to reproduce or the environment is too stressful, they may choose to divorce and look for a high-quality partner again.

Little blue penguins on Phillip Island | Phillip Island Nature Parks

The annual reproduction of little blue penguins is also closely related to their divorce rate. Researchers have found that the higher the divorce rate before the breeding season, the lower the success rate of the next generation hatching and growing up and leaving the nest - after the penguin couples divorce, they each have to spend time dating and looking for a new partner, which delays the reproduction time and sometimes even makes them miss the breeding season.

Environmental conditions and foraging behavior also affect the breeding success rate of little blue penguins. One penguin couple goes out to sea to find food, while the other takes care of the children on land, waiting for the partner to bring food back from afar. If the environment is harsh and food resources are scarce, the penguin responsible for foraging will need to swim a long way to reach the foraging area. In this way, the chicks will be forced to go hungry for a long time between meals, and the partner who takes care of the children will have to abandon the nest and go out to find food due to insufficient fat reserves, and the chicks will not be easy to survive.

Little blue penguin chick hiding in its nest | Glen Fergus / Wikimedia Commons

This study shows that the lower the penguin divorce rate, the more favorable the environmental conditions, and the shorter the foraging time, the higher their reproductive success rate. These indicators can help us comprehensively monitor the breeding trends of penguins and better protect them.

Feeding squirrels

If squirrels are constantly fed by humans, the shape of their skulls will change.

In a new study, researchers compared the skeletons of red squirrels before and after they were fed by humans. From 113 skulls and 387 jaws, they found some patterns - the skulls of squirrels that had eaten a lot of peanuts were flatter than those of other squirrels, and the attachment points of the jaw muscles were closer to the joints responsible for chewing, which would weaken their bite force .

This study analyzed how the head structure of squirrels is affected by human feeding | References [2]

The red squirrel is the only native squirrel species in the UK. Since the late 19th century, when the gray squirrel came to the UK as an invasive species, the number of red squirrels has dropped dramatically, and now they have become protected animals. Because of their love for squirrels, people in a small town in the UK have spontaneously fed red squirrels since the 1990s. Today, peanuts fed by people have become the main food source for local red squirrels. But the shell of peanuts is very soft, and squirrels in the wild usually eat pine nuts or hazelnuts, which have hard shells and require a strong bite force to open the shell and eat the flesh inside.

This study shows that long-term consumption of soft-shelled nuts reduces the ability of squirrels to eat hard-shelled nuts . They will become overly dependent on peanuts fed by humans. Once the supply of peanuts decreases, they will not be able to adapt to those hard-shelled nuts, which is very detrimental to their survival. Human feeding can allow wild animals to obtain sufficient food in the short term, but in the long run, their ability to adapt to the wild will be reduced, which will have disastrous consequences.

Love it, don't feed it | Peter Trimming / Wikimedia Commons

The smallest cat

300,000 years ago, the world's smallest cat lived in China.

Recently, in Anhui Hualong Cave, researchers from the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences discovered a very miniature cat fossil and named it Prionailurus kurteni. The Kurteni cat is only the size of a palm , which is similar to the smallest existing cats - the rusty-spotted cat and the black-footed cat, or even smaller. Scientists estimate that this cat weighs only about 1 kilogram and is between 35 and 50 centimeters long. It may be the smallest cat ever discovered.

Fossils of Kopi lucidus | References [3]

The Kopi Lupus belongs to the genus Ocelot . The genus Ocelot is found in eastern, southeastern and southern Asia. The four existing species include the ocelot, fishing cat, flat-headed cat and rusty-spotted cat. The ocelot of the Southeast Asian islands is sometimes considered a separate species, the Javan ocelot. Unfortunately, fossil remains of the genus Ocelot are very rare because they live in forest environments and their bones degrade faster, making them difficult to preserve.

A living relative of the Kopi Lupi, the rusty-spotted cat, also smaller | Davidvraju / Wikimedia Commons

The Hualong Cave where the Koi's leopard cat was discovered was a place where early humans lived. Researchers speculate that the food residues left by humans may have attracted mice to live here, and the leopard cat entered the cave to hunt mice . And it is precisely because of the protection of the cave environment that its bones have been successfully preserved, providing modern humans with valuable research materials, allowing us to trace the origin of cats - previous molecular biological evidence showed that the genus Leopard Cat, the genus Felis and the genus Manul had a common ancestor, and the inclination angle of the Koi's leopard cat's teeth provided fossil evidence for this conclusion for the first time.

Precision control of octopus

Octopuses have eight arms and hundreds of suckers. How do they achieve precise control?

Each octopus arm has a huge nervous system, and the number of neurons in the eight arms combined is more than that in the brain. In a recently published paper, researchers used cell labeling and imaging tools to find that the neurons in the octopus arms are segmented - they are divided into columnar segments, and each arm is composed of multiple segments; the segments are separated by diaphragms, and neurons and blood vessels are connected from the diaphragms to nearby muscles to control muscle movement.

Octopuses have exquisite motor control thanks to a segmented nervous system | Cassady Olson

In the octopus's arms, the nerve segments are not completely isolated, and neurons in multiple segments can connect to different areas of the muscles to control movement together. These separate but closely cooperating neural networks give the octopus's arms almost unlimited degrees of freedom, allowing them to bend and curl flexibly, easily grabbing objects and capturing prey.

The octopus's nervous system also creates a "topographic map" for each sucker. The outer edge of each sucker is full of neurons that connect and merge into nerve segments . The suckers are also covered with sensory receptors. Octopuses can not only use the suckers to move and fix their bodies, but also use them as a combination of hands, noses and tongues to fully perceive what the suckers touch. In this way, they can lurk on the seabed for a long time and use their arms to explore the surrounding environment.

Each of an octopus's suckers houses a powerful motor and sensory system | Cassady Olson

Saving Red Deer

A Canadian elk that was entangled in a rope was finally rescued.

Recently, at an ice climbing area in Colorado, USA, ice climbers found a hapless bull elk whose antlers were entangled in a rope and had been trapped for some time . The animal had several abrasions and was exhausted from the struggle.

Rescuing an entangled elk | Colorado Parks and Wildlife

After the rescue team arrived at the scene, they injected a sedative into the deer and covered its head with a ski mask to protect its eyes. They cut the ropes wrapped around the deer's antlers, but they encountered another problem: how to get the 300-kilogram deer down from the cliff? With the help of ice climbers, they tied a rope under the deer's chest and another along its antlers, and used a simple system to slowly lower it down the cliff .

Elk being slowly moved off a cliff | Colorado Parks and Wildlife

After more than two hours, the elk was finally placed on flat ground, where rescuers reversed the effects of the sedative, and 12 minutes later, the elk woke up and ran down the valley, finally leaving safely.

This is not the first unlucky elk. Objects such as human clotheslines, fences and hammocks are potential threats to horned ungulates . Once they are entangled, it is difficult for them to free themselves. In areas where wild animals often appear, the traces left by us humans can easily have an adverse impact on animals.

Another entangled elk | KOMO news

One-eyed wolf queen

The oldest wolf queen in Yellowstone Park died in a battle.

907F is almost 12 years old, the fifth oldest wolf ever recorded in Yellowstone Park . He inherited the position of wolf king after his aunt died. When he was almost 4 years old, he accidentally lost his left eye and then survived an infectious skin disease. But he still maintained a strong fighting power in the face of many ups and downs, until recently, he was fatally injured in a battle to defend his territory with a nearby wolf pack and died a few days later.

The majestic One-Eyed Queen 907F | Yellowstone Wolf and Cougar Project

Because life in the wild is full of dangers, the average age of wolves is only 3 to 4 years old. Even in protected areas such as Yellowstone Park, very few wolves can live to be over 10 years old. 907F can live to this age because of its extremely cautious character - it will actively avoid humans, not easily approach roads with vehicles, and always avoid other predators. It lives in a large wolf pack, with many companions who compete with it for territory with other wolf packs and help it hunt large prey such as elk, which also reduces its risk of death.

907F was wearing a radio collar, which informed park staff of his death | Taylor Rabe

907F was also the most successful wolf in the park's history. From the time it reached sexual maturity, it gave birth every year, and gave birth to a total of 10 litters of pups in its lifetime. One of its sons is now the leader of the wolf pack. After 907F's unfortunate death, park staff and wildlife conservationists are mourning for it, but it is gratifying that it lived its life the way of a wolf and died the way of a wolf - it was not killed by a hunter or hit by a car, and it was still protecting its own wolf pack until its death.