Your memory may be surpassed by chimpanzees | Nature Trumpet

Welcome to the 50th issue of the Nature Trumpet column. In the past half month, we have collected the following natural news and research worth reading:

1) Chimpanzees recognize their family after being separated for 26 years

2) More than 110 elephants died due to drought

3) Parrots are good eaters. Soak dry bread in water first.

4) Cats can pick up balls, which is a natural skill

5) Humans had their first conversation with a humpback whale

6) Meerkats are cute, but they have a bloodthirsty leader

Chimpanzees recognize family members

Chimpanzees and bonobos can recognize friends and family members even after not seeing each other for decades.

In a new study, scientists showed chimpanzees and bonobos some photos of their own kind, some of which were strangers they had never seen before, and some of which were old acquaintances they had lived with. Scientists used eye-tracking cameras to record how long their eyes stayed on different photos; the results showed that they stayed on the photos of old acquaintances for significantly longer, indicating that they recognized each other .

In the experiment, chimpanzees drank juice while looking at pictures of other chimpanzees on a monitor | References [1]

Sometimes zoos transfer orangutan companions to other zoos to avoid inbreeding. A bonobo named Louis hadn't seen his sister and nephew in 26 years , but when he saw their photos again, he stared at the two long-lost family members for a long time.

How would the bonobos react when they saw their family members again after more than 20 years? Scientists found that they were not excited, but suddenly froze , even stopped drinking juice, and were completely attracted by the photos , as if they were carefully recognizing each other's faces and recalling their long-ago past.

The screen shows a strange ape and a companion that he hasn't seen for many years | References [1]

This is the first time that humans have found that other animals retain such long-term memories , and our closest relatives on the evolutionary tree are so similar to us. Before this, dolphins had the longest memory retention in the scientific record, and they can remember sounds for up to 20 years.

Elephants dying in drought

In Zimbabwe, more than 110 elephants have died in the drought .

The incident happened in recent months. Due to the hot weather and the lack of rain, elephants in Hwange National Park cried desperately at the dry water holes until they collapsed.

This desperate elephant finally got the rain that was six weeks late | References [2]

Most of the elephants that failed to survive the drought were old, young, and sick. When they were found, they were already rotting corpses with shriveled skin, but their tusks were intact, indicating that they did not die from poaching. In order to prevent poachers from discovering their corpses and cutting off their tusks for illegal trade, forest rangers could only carefully remove their tusks.

Since the 1970s, tens of thousands of elephants have been killed by poachers in Africa. After the establishment of national parks and protected areas , poaching has been greatly reduced and the number of elephants has successfully increased. According to a survey last year, there are about 228,000 elephants in the Kavango Zambezi Transfrontier Conservation Area, more than 10,000 more than in 2016.

Elephants drinking from human swimming pools | References [2]

But now, increasingly scarce resources and climate change have brought new dangers to them . It is estimated that the number of elephants in Zimbabwe has exceeded the local capacity by two times, and an elephant needs 200 liters of water and 140 kilograms of food every day. They will inevitably face resource shortages. Coupled with the arrival of high temperatures and drought, elephants have to travel long distances to find food and water, and even enter human settlements to find water to drink.

Parrot Soak Bread

Parrots are really good at eating. They even soak bread crackers in water before eating them!

Recently, two veterinarians discovered that a Goffin's cockatoo named Pippin would not put the hard bread fed by humans into its mouth immediately, but would first go to the water bowl, soak the bread in the water for a few seconds, wait for it to become moist and soft, and then take it out to eat .

Teacher Niaowu said that hard bread irritates the throat and is only delicious when it is softened! | Reference [3]

The veterinarian continued to observe the parrots eating and found that other parrots began to follow suit and soaked bread like Pippin did . Seven of the 18 birds learned to soak bread, but the soaking time was different, and each bird might like a different degree of moisture. Moreover, the parrots seemed to realize that only hard bread tasted better after soaking in water - if they got seeds, dried fruits and other foods, they would eat them directly without soaking them in water.

Parrots are real foodies. In order to reach the water bowl to soak the bread, they will put in a lot of effort, such as climbing railings and moving obstacles away in order to reach the water bowl.

People put obstacles in front of parrots, forcing them to climb over mountains and hills to get a meal. The birds are good, but people are bad! | Reference [3]

So far, Goffin's Cockatoos in the wild have not been found to eat food soaked in water , but this is probably because it is difficult to find a suitable water source in the wild, and they rarely encounter food that tastes good only after soaking in water. Perhaps a captive parrot accidentally dropped a piece of hard bread into the water, opening the door to a new world and discovering this new way of eating.

Cat fetching ball

Some cats can fetch balls, and this is their innate skill.

In a new study, researchers surveyed nearly 1,000 cat owners and found that 94% of cats who could fetch balls learned to do so spontaneously , without any deliberate training from their owners. Many people recreated the first time their furry children fetched something - they accidentally dropped a small object like a bottle cap, and the cat ran over to pick it up, and they and the cat began a cycle of throwing and picking up bottle caps.

Cat fetches a ball | Nancy Wong / Wikimedia Commons

As a cat owner, you may think: cats are so smart, they learned to pick up the ball without being taught! You are naive. In fact, cats are training you to play the game of picking up the ball with them .

Researchers found that cats, rather than humans, are more likely to initiate the ball-picking game, and it is also cats who decide when the game ends (cats: humans are just my ball-picking machines). Cats also decide what to throw - they don't necessarily like cat toys, and hair strings, packaging bags, and small pieces of paper they pick up at home will become their favorite treasures, and they will bring them to their owners to signal "Come and play with me!"

Shoelaces can also become a favorite toy for cats | bayral / Wikimedia Commons

Dogs that can retrieve balls are more common , and this is also based on facts. The ancestor of dogs, wolves, are pack animals with stronger sociality and will bring prey back to the pack; and under human selective breeding, the dogs that can reproduce are often those that are more interactive with humans.

Cats are different. They are solitary and do not have the tradition of bringing prey to the group. Although mother cats will bring food to their kittens, this does not explain why pet cats love to play fetch - after all, there are both male and female cats who play fetch. At present, researchers do not know the origin of cats' fetching behavior . It seems that cats' impulsive play activities have posed a problem for humans.

Cat: You were trained by the two-legged beasts to fetch a ball, and I trained the two-legged beasts to throw a ball to me! | Trish Hamme / Wikimedia Commons

Talk to humpback whales

Recently, for the first time, humans spoke to humpback whales in their own language.

Humpback whales are known as the singers of the sea, and their calls are loud and rhythmic. Scientists have been trying to translate their language. This time, scientists used underwater speakers to play the calls of humpback whales representing greetings in the sea . A humpback whale named "Twain" heard the call, swam to their boat, swam around them, and made a response sound .

Humpback whales: What are you doing here? Have you eaten? | NOAA's National Ocean Service

Next, the scientists played more humpback whale calls, and Twain responded one by one, and the "conversation" lasted for 20 minutes . They recorded Twain's calls and analyzed the intervals between the sounds, and found that it was indeed not a random call, but a serious response after hearing the sounds played by humans.

Humpback whales hang out next to human boats | Robbie Shade / Wikimedia Commons

Scientists have also documented humpback whales' communication behaviors other than vocalization. Humpback whales sometimes create bubble rings to trap small fish and eat them when they can't escape. However, they occasionally create bubble rings in front of humans , possibly to convey a unique message to humans.

In the sci-fi movie Star Trek, humpback whales become a communication window between humans and aliens. Although this is a fictional story, scientists believe that humpback whales can indeed be the starting point for our search for extraterrestrial intelligent life - if we can decipher the language of whales and successfully communicate with them, we may also be able to decipher the language of other non-human creatures, including aliens.

Female meerkat

Meerkats are cute animals with big eyes, but they also have a fierce side.

Meerkats standing in a row | Catatine / Wikimedia Commons

Meerkats are matriarchal, with a meerkat group consisting of up to 50 meerkats, led by a female chief. The chief is almost the only female in the group that can reproduce , and can reproduce several times a year. All the children she gives birth to are raised by her subordinates.

However, if a female subordinate attempts to reproduce, the clan leader will expel her from the clan; if the clan leader finds any cubs that are not her own, she will brutally kill and eat the children .

Meerkats | H. Zel / Wikimedia Commons

In a new study, scientists studied blood samples of meerkats and found that meerkats have higher cortisol levels than group members, indicating greater stress ; but the group leaders also have greater androgen levels and body weight, which is beneficial to their reproduction . More importantly, female group leaders have stronger immunity and can better resist infection , which gives them more energy to maintain their status and give birth to offspring.

When leadership requires a stronger body | Petruss / Wikimedia Commons

The immune genes of female meerkats are very similar to those of wild male baboons. Among baboons, leaders also need to compete for positions, and baboons with better health and more energy can obtain higher social status and mating rights.

Author: Cat Tun

Editor: Mai Mai

This article comes from GuokrNature (ID: GuokrNature)