Saving the Northern White Rhino: In vitro fertilization brings hope! | Nature Trumpet

Welcome to the 52nd issue of the Nature Trumpet column. In the past half month, we have collected the following natural news and research worth reading:

1) Rhino embryo transplantation is successful, bringing new hope to the northern white rhino

2) These little animals don’t even sleep to mate

3) The ocean is too noisy, so humpback whales run back and forth to sing

4) Sea otters save kelp forests because they can eat

5) The lonely giraffe finally moved to a new home

6) This carefree mountain lion unfortunately died in a car accident

Rhino embryo transfer

A rhino successfully became pregnant through embryo transplantation , giving new hope to the endangered northern white rhino.

A successfully transplanted rhino embryo | Jon Juarez / AP

White rhinos include two subspecies, the southern white rhino and the northern white rhino. There are about 20,000 southern white rhinos left, but the northern white rhino is only one step away from extinction - there are only two northern white rhinos left in the world, and both are female. In 2018, the last male northern white rhino, Sudan, died. Scientists have frozen and stored the semen of him and the other four deceased male northern white rhinos, hoping that one day they can save the northern white rhino through in vitro fertilization .

Sudan, the last male northern white rhino, was protected by armed guards in Kenya until his death in 2018 to prevent poaching | Georgina Goodwin

Scientists conducted experiments on southern white rhinos - they collected rhino eggs and sperm, completed in vitro fertilization and transplanted the embryos into a female southern white rhino. The female southern white rhino successfully became pregnant , but unfortunately, it had died of an infection, and the successfully transplanted embryo was not discovered until the autopsy.

Najin, 30, one of the last two northern white rhinos on Earth | Ben Curtis / AP

This experiment proves that rhinos can become pregnant through artificial embryo transplantation, which brings a glimmer of new hope to the northern white rhino. Unfortunately, for the northern white rhino, this good news may have come too late, and the hope of rebuilding the entire northern white rhino population is still slim. The existing rhinos are still poached and killed for their horns , so protecting them is also a top priority.

Too busy mating to sleep

These little animals are so busy mating that they don’t even have time to sleep!

Time management master! | Catching The Eye / Wikimedia Commons

It comes from the genus Antechinus swainsonii, a small marsupial living in Australia. During the breeding season, males devote themselves to it, and their activity level increases significantly. They are busy looking for the opposite sex from morning to night, so they don't get enough sleep every day . Recent studies have found that during the three-week breeding season, they sleep three hours less than normal every day, and some even cut their sleep time in half.

Honey, here I come!! | jamesbennett / wildinaturalist

However, such "time management" has serious consequences. The mating season is short and intense, but it only happens once in a male's life - after the mating season is over, the male will die, and even if he survives, he will become infertile .

However, don't worry, night owls here, although scientists have not figured out why they die after the mating season , at least lack of sleep is not the only reason. Some people speculate that the increase in cortisol in males during the breeding season may lead to death; but researchers believe that for broad-footed marsupials, cortisol may be an adaptive advantage that allows them to stay awake to mate, and is not the direct cause of their death. In short, their cause of death is still unclear.

Researchers release captured broad-footed marsupials | Francesca Leonard

Unlike males, female broad-footed marsupials do not suffer from obvious sleep deprivation during the mating season , but their average sleep time is still a little shorter than usual. Considering that males are so active, scientists speculate that females may be woken up.

Life of a Humpback Whale

Because the sea is so noisy, humpback whales have to sing at off-peak times.

In a recently published study, scientists used underwater monitoring equipment to figure out the daily lives of 217 humpback whales near Maori Island - they sing in the ocean during the day and swim near the shore to sing at night .

A singing humpback whale | Dr. Louis M. Herman / Wikimedia Commons

Male humpback whales are among the best singers in the sea, and their singing is also a signal for them to find mates. During the breeding season, the density of local humpback whales is very high. If they all crowded in shallow waters to sing during the day, their voices would overlap and interfere with each other. Therefore, they choose to spread out in the ocean, keep a certain distance , and give each other space to sing.

However, at sunset, the male humpback whales will return to the shallow waters near the sea - this time because the sea is too noisy . Every night, all kinds of creatures in the sea begin to make sounds, and the humpback whales have to avoid them and sing on the quieter shore.

They're so noisy, they're affecting my performance, so I'll go first | Sylke Rohrlach / Wikimedia Commons

They run back and forth like this every day to prevent their songs from being covered by other people's voices. Many current studies focus on the impact of human noise on marine mammals, but ignore the original sound interactions in the ocean . The behavior of whales is not only affected by food, tides and seasons, but also by the sound environment created by other marine life, which also affects their daily routines.

Sea otters make great contributions

Otters are not only cute, we are also great contributors to the ocean!

I'm almost embarrassed by all the praise! | Stan Shebs / Wikimedia Commons

In the 19th century, sea otters were hunted to near extinction in California for their fur, with only a few otters surviving on the central coast. Later, as protection measures increased, the sea otter population here slowly grew. A new study finds that it was these few remaining sea otters that saved the kelp forests.

Over the past 100 years, kelp forest cover has increased almost everywhere on the central coast, where sea otters are present, with an overall increase of 56% . In contrast, in the northern and southern regions without sea otters, kelp forest canopies have decreased by 63% and 52%, respectively, which is a stark difference from the areas with sea otters.

I'm just protecting the seaweed (I'm not greedy!) | neil fisher / YouTube

The way sea otters protect kelp forests is by eating sea urchins! Sea urchins feed on kelp. If there are no natural enemies, they will plunder the kelp forests like locusts, creating one "sea urchin wasteland" after another. Fortunately, sea urchins are one of the favorite foods of sea otters. Sea otters work hard to eat, so the kelp forests can escape the disaster and grow again.

Sea urchins eat away kelp forests, turning them into "urchin wastelands" | Michael Langhans / UC Santa Cruz

Healthy kelp forests have many benefits for both marine ecosystems and humans. They create shelter for small fish, provide food for a variety of marine life such as crabs and abalone, serve as nurseries for fisheries, and reduce coastal erosion from storms.

Healthy kelp forests are home to marine life | Monterey Bay Aquarium

Giraffe Moving

Recently, a lonely giraffe finally moved and was able to make friends!

Lonely Benito | Christian Chavez / AP

Benito, who was born in 1917, lived alone in a zoo near the border of Mexico and the United States. The climate there was extreme and his living conditions were harsh - a garbage-strewn enclosure with no grass or shelter.

Animal protection activists actively spoke out for Benito and successfully persuaded the local government to relocate him. His new home is an African wildlife park in central Mexico, where the environment is more similar to the natural habitat of giraffes, and there is already a large herd of giraffes there , where Benito can make new friends.

Benito's own convertible | Jose Luis Gonzalez / Reuters

However, ordinary cars cannot accommodate the giraffe when it is moving! The staff designed an open-top carriage over 5 meters high for Benito, so that Benito's head can stick out of the carriage, and covered his body with waterproof cloth to protect him from the cold and wind and rain. The carriage was fully stocked with straw, water and vegetables, and equipped with electronic equipment to detect temperature. There was also a team of experts and guards accompanying Benito to protect him.

Benito eats and drinks well before leaving | References [5]

Benito's moving journey is 2,000 kilometers and takes a total of 50 hours. Before embarking on the journey, local residents who love Benito said goodbye to him together. Although they can no longer see Benito in the zoo near their home, everyone is happy that he can live a better life.

Mountain lion car accident

A beloved mountain lion recently died in a car accident.

An Uno with a cloudy eye and a tracking collar used in research | Mark Girardeau/Orange County Outdoors

Its name is Uno, a female mountain lion with a unique appearance and personality. Due to an old injury, one of its eyes is cloudy, which makes it particularly easy to identify and well-known in the local area.

It neither avoids humans nor attacks them, and has a king's contempt - although it always encounters humans hiking, it always passes by leisurely and never pays any attention to them; when humans line up to pay at the park entrance, it just walks in with a swagger (of course, they don't need to pay).

Uno is often photographed | California Mountain Lion Project

However, on January 18, when Uno was crossing the highway as usual, she was hit by a speeding vehicle . People tried to treat her, but she suffered severe injuries to her head and chest and died without receiving treatment. Even more unfortunately, she was pregnant, and the unborn lion cubs never had the chance to see the world.

Uno had four children in his life, two of whom were also killed by cars, one of whom died not far from where Uno's car crashed. Of the other two children, one died of illness and the other disappeared. Uno and his children, like many more mountain lions, were loved by humans but also died at the hands of humans .

Dead mountain lion on the road | CONCER / Wikimedia Commons

A 2015 study found that 46% of mountain lion deaths occurred in traffic accidents. And these are only the incidents that people have discovered and recorded. Many more animals die on human roads when no one notices them.

Author: Cat Tun

Editor: Mai Mai