4 . On Inaccessible Island, you hear the sound of the Inaccessible Island rails (秧鸡) everywhere. The small flightless birds move around, feeding on worms and berries. During a trip in 2011, it took days for Stervander, then a doctoral student, to spot one. “Even then, you see something little and dark, running for a second, and that’s about it,” he says. Catching one, though, proved easy. When scientists played a recording of the bird’s call, a male and female ran into the net a few minutes later.

Inaccessible Island rails live only on Inaccessible Island. “No one knew the history,” says Stervander, now a research fellow at the University of Oregon. He aimed to answer the question about these birds: How did they get to Inaccessible Island to begin with?

The first scientist to describe the rail was Percy Lowe. He thought the bird was from Africa and had always been flightless. In his view, it had arrived at the island by walking over land bridges. But now the science of plate tectonics (板块构造论) suggests that’s not the case. In a recent paper, Stervander and his colleagues give evidence for a different version.

After studying the genome (基因组) of the rails, scientists found the Inaccessible Island rail’s closest relative — the crake in Uruguay. Both birds are related to the black rail in America. The finding suggests the ancestors of these birds could fly. That means Inaccessible Island rails flew to their present home, and like many birds living on islands with no predators (捕食者), they gradually lost the ability to fly. Flying takes energy, so if there’s no reason to fly, it’s more practical not to.

On this island, there’s a growing population of rails, but they’re fragile. Should a predator reach the island, it could make quick work of the birds. People on nearby islands are careful to avoid introducing any predators to Inaccessible Island, and the risk is low, given how hard it is to get there. For now, the rails live peacefully in a place where few humans are eager to go.

5 . The North Atlantic right whale is one of the world’s most endangered large whale species. Its population loss appears to be slowing. But scientists warn that the large sea animals still face threats.

The National Oceanic and Atmospheric Administration (NOAA) says that by the early 1890s, commercial whalers almost destroyed the species. They got their name from being the “right” whales to hunt because they floated when they were killed. Commercial whale fishing is no longer a threat, but its population has never fully returned. They have been protected for many years now.

Right whales primarily occur in Atlantic coastal waters on the continental shelf, although they also are known to travel far offshore, over deep water. They migrate seasonally and may travel alone or in small groups. In the spring, summer, and into fall, many of these whales can be found in waters off New England and further north into Canadian waters, where they feed and mate.

Recently, the North Atlantic Right Whale Consortium (NARWC) said the population decrease appears to have leveled off. A strong birthing year in 2021, when 18 baby whales, or calves, were born, kept whale population numbers up. However, the organization warned that the high number of deaths faced by whales from getting caught in fishing equipment or struck by ships remains a major problem for the whales.

“The news is less bad than it has been. My heart is a little less heavy, but certainly not light or hopeful,” said Philip Hamilton. “It shouldn’t be dependent on the whales to give birth to enough calves to reverse what we’re doing to them.”

Scientists say as waters have warmed, the whales must travel outside of protected areas of the ocean in search of food. That has left them open to strikes with large ships and getting trapped in commercial fishing equipment. Those are the biggest causes of early death.

Many fishermen have opposed proposed fishing restrictions that they fear would hurt their business. But environmental groups want new rules to save the species, including one to make ships slow down for whales.

6 . In October, 2023, agricultural officials in California discovered three Mediterranean fruit flies, or Medflies for short, in the Leimert Park neighborhood of Los Angeles.

Medflies are one of the most serious threats faced by farmers worldwide. The flies lay their eggs in over 300 kinds of fruits and vegetables. When the eggs hatch, they turn into worm-like larvae that can ruin the produce. The problem is that it can be difficult to know that the flies are there until it’s too late. The fruits and vegetables still look normal even after the eggs are laid inside. So the damaged fruits and vegetables can be sent to other places, allowing Medflies to spread.

The first Medfly was detected in California in 1975, but it wasn’t until between 1980 and 1982 that the flies reached outbreak levels. There were doubts about the government’s ability to control them. Then-governor Jerry Brown authorized a campaign spreading the insecticide called Malathion to knock out the flies. Californians claimed that the chemical being spread across their neighborhoods could kill the flies, but surely it could affect their health negatively. The state declared the flies were controlled in 1982. California stopped the campaign in 1990.

After the three were discovered in October, the government set up a 233-square-kilometer special area. This means that no produce (fruits, nuts, or vegetables) can be moved out of that area. That may seem extreme, since only three Medflies were found, but experts believe there’re probably more out there. “It’s really important to get on top of this fast, or growers would go out of business,” said one of the experts.

Luckily, California has developed a program to control Medflies. The program involves using planes to drop millions of male Medflies over the area. All of them have been treated so that they can’t help occasion new Medflies. The males are sterile, which means that even though they can mate with female Medflies, the resulting eggs will never grow and are so small that they don’t affect crops.

7 . When Mark Twain first set eyes on Honolulu in 1866, he observed that the trees were so thick that they blocked the sunlight, rocks from past volcanic eruptions covered the corals — and lovely cats were everywhere.

Nearly 160 years later, however, the descendants (后代) of the cats that so pleased Twain are now widely seen as a threat to the islands. The wild cat, explains the Hawaii Invasive (侵入的) Species Council (HISC), has become one of the state’s most “disastrous” animals.

Cats were first brought to Hawaii aboard European colonists’ ships, where they killed rats and mice. As their number in their new home grew during the 19th century, birds started to disappear. At least 30 types of native bird became rarer or went extinct between 1870 and 1930 as they were exposed to their new enemies, according to the US Geological Survey.

Toxoplasmosis (弓形虫病) is a disease caused by a parasite (寄生虫) that reproduces in the digestive systems of cats, and then pollutes soil and water through their faces (粪便). A new study determined that two spinner dolphins found on the Hawaiian coast died of toxoplasmosis. From these findings the authors suggest that at least 60 spinner dolphins have died of the parasite over the past 30 years.

A bill that could have directed the HISC to kill cats using poisoned food, as Australia has done, died in the state legislature earlier this year. Animal-lovers prefer to focus on catching wild cats, removing their sex organs and releasing them so that they have no kittens. But HISC contends that such programmes do not actually help control cat numbers. Ms West suggests that people are too quick to blame the cats, when there is another cruel animal. “People have to stop abandoning these poor cats,” she says. “It’s not really a cat problem. It’s a human problem.”

10 . Harvard scientists have engineered a group of fish that swims autonomously. Researchers say the experiment could advance pacemaker(起搏器) technology and improve the development of artificial hearts for humans.

Researchers built the fish using paper, two parts of heart muscle tissue — one on the left side and one on the right — and a plastic fin. A contraction on one side caused the muscle on the other side to stretch. The stretching then caused those cells to contract, which moved the tail from side to side and allowed it to swim on its own. The muscle cells were from human stem cells. The researchers also engineered an autonomous pacing node, which acted like a pacemaker by controlling the rhythm and frequency of the contractions.

The fish moved autonomously for over 108 days, which is equal to 38 million beats, the study states. Because heart cells constantly rebuild themselves, which takes about 20 days, the fish cells rebuilt themselves a total of about five times over, says Kit Parker, a professor from Harvard University who led the research.

Years ago, Parker was disappointed with the state of heart treatment. “It occurred to me in 2007 that we might have failed to understand the fundamental laws of muscular pumps,” he said in a 2012 statement. Then, on a trip to the museum with his daughter, he spotted a special fish. “I’m looking at it, thinking, ‘It pumps, it looks like a heart pump, and I could build that thing.’” In 2012, his team created a fish that swam using rat heart cells, and then a ray fish with rat heart cells in 2016.

Though the researchers say the fish is a step forward for heart research, it could be years before it leads to the creation of an artificial heart, says Michael Schneider, a professor at Imperial College London, who wasn’t involved in the study. But that doesn’t dismay Parker. “I think other methods will be faster than us,” says Parker.   “But in the long run, creating tissue that relies on the patient’s own cells could offer unexpected benefits.”