1 . A lone humpback whale travelled more than 9,800 kilometers from breeding areas in Brazil to those in Madagascar, setting a record for the longest mammal migration even documented.

Humpback whales are known to have some of the longest migration distances of all mammals, and this huge journey is about 400 kilometers father than the previous humpback record. The finding was made by Peter Stevick, a biologist at the College of the Atlantic in Bar Harbor, Maine.

The whale's journey was unusual not only for its length, but also because it travelled across about 90 degrees of longitude from west to east. Typically, humpbacks move in a north-south direction between cold feeding areas and warm breeding grounds.

The whale, a female, was first spotted off the coast of Brazil, where researches photographed its tail fluke and took skin samples to determine the animal's sex. Two years later, a tourist on a whale-watching boat snapped a photo of the humpback near Madagascar.

To match the two sightings, Stevick's team used an extensive international catalogue of photographs of the undersides of tail flukes, which have distinctive markings. Researchers routinely compare the markings in each new photograph to those in the archive.

The scientists then estimated the animal's shortest possible route: an are skirting the southern tip of South Africa and heading north-east towards Madagascar. The minimum distance is 9,800 kilometers, says Stevick, but this is likely to be an underestimate, because the whale probably took a roundabout way to feed on frill in the Southern Ocean near Antarctica before reaching its destination.

Most humpback-whale researches focus on their efforts on the Northern Hemisphere because the Southern Ocean near the Antarctica is a tough environment and it is hard to get to, explaining Rochelle Constantine, who studies the ecology of humpback whales at the University of Auckland in New Zealand. But, for whales, oceans in the Southern Hemisphere are wider and easier to travel across, says Constantine. Scientists will probably observe more long-distance migrations in the Southern Hemisphere as satellite tracking becomes increasingly common, she adds.

Daniel Palacios, an oceanographer at the University of Hawaii at Monoa, says that record-breaking journey could indicate that migration patterns are shifting as populations begin to recover from near-extinction and the population increases. But the reasons why whale did not follow the usual migration routes remain a mystery. She could have been exploring new habitats, or simply have lost her way. “We generally think of humpback whales as very well studied, but then they surprise us with things like this,” Palacios says. “Undoubtedly there are a lot of things we still don't know about whale migration.”

A massive fire tore through the main market in the city of Hargeisa in northern Somalia overnight, injuring about two dozen people and     1    (destroy) hundreds of businesses, officials have said.

Images     2    (post) on social media showed flames and huge clouds of smoke in the night sky over the city, the capital of the breakaway region of Somaliland. The cause of the blaze     3     devastated the sprawling Waheen market, the lifeblood of the city and home     4     an estimated 2,000 shops and stalls, is not yet known.

Officials said it started on Friday evening but was largely brought under control by dawn on Saturday, although some small areas were still burning.

“The town has never witnessed such a massive calamity,” Hargeisa’s mayor, Abdikarim Ahmed Mooge, told reporters at the scene. “This place was the economic centre of Hargeisa and     5     the firefighters’ best efforts made to contain the fire, the market is destroyed.” He said the blaze could have been brought under control before causing such extensive damage but that the firefighters’ attempt     6    (deny) due to access problems. The vast market is a crowded warren of shops and makeshift stalls, with no proper streets, only narrow pathways.

The Somaliland president, Muse Bihi Abdi, said during a visit to Waheen     7    about 28 people, nine of them women, were injured, but that so far no loss of life     8    (report). He said the government would be releasing one million dollars to help with the emergency response to the disaster.

Hargeisa chamber of commerce chairman Jamal Aideed said the loss of the market was immense     9     it accounted for 40% to 50% of the city’s economy.

“I have lost everything tonight, this fire was the biggest I have ever seen in my life,” said market trader Bashi Ali. “I had several businesses in the market and all of them burned to ashes.     10    we can learn from this disaster is to plan the market well,” he added.

4 . There was a time when we thought humans were special in so many ways. Now we know better. We are not the only species that feels emotions, or follows a moral code. Neither are we the only ones with personalities, cultures and the ability to design and use tools. Yet we have all agree that one thing, at least, makes us unique: we alone have the ability of language.

It turns out that we are not so special in this aspect either. Key to the revolutionary reassessment of our talent for communication is the way we think about language itself. Where once it was seen as an unusual object, today scientists find it is more productive to think of language as a group of abilities. Viewed this way, it becomes apparent that the component parts of language are not as unique as the whole.

Take gesture, arguably the starting point for language. Until recently, it was considered uniquely human - but not any more. Mike Tomasello of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and others have collected a list of gestures observed in monkeys and some other animals, which reveals that gestures plays a large role in their communication. Ape(猿) gestures can involve touch, vocalising or eye movement, and individuals wait until they have another ape’s attention before making visual or auditory gestures. If their gestures go unacknowledged, they will often repeat them.

In an experiment carried out in 2006 by Erica Cartmill and Richard Byrne from the University of St Andrews in the UK, they got a person to sit on a chair with some highly desirable food such as banana to one side of apes and some undesirable food such as vegetables to the other. The apes, who could see the person and the food from their enclosures, gestured at their human partners to encourage them to push the desirable food their way. If the person showed incomprehension and offered the vegetables, the animals would change their gestures - just as a human would in a similar situation. If the human seemed to understand while being somewhat confused, giving only half the preferred food, the apes would repeat and exaggerate their gestures - again in exactly the same way a human would. Such findings highlight the fact that the gestures of the animals are not merely inborn but are learned, flexible and under voluntary control - all characteristics that are considered preconditions for human-like communication.

6 . Aviculturists, people who raise birds for commercial sale, have not yet learned how to create similar conditions to the natural incubation (孵化) of parrot eggs in the wild. They continue to look for better ways to increase egg production and to improve chick survival rates.

When parrots incubate their eggs in the wild, the temperature and humidity (湿度) of the nest are controlled naturally. Heat is transferred from the bird’s skin to the top of the eggshell, leaving the sides and bottom of the egg at a cooler temperature. This temperature difference may be vital to successful hatching. Nest construction can contribute to this temperature difference. Nests of loosely arranged sticks, rocks, or dirt are cooler in temperature at the bottom where the egg contacts the nesting material. Such nests also act as humidity regulators by allowing rain to drain into the bottom sections of the nest so that the eggs are not in direct contact with the water. As the water that collects in the bottom of the nest changes into gas, the water vapor rises and is heated by the incubating bird, which adds significant humidity to the incubation environment.

In artificial incubation programs, aviculturists remove eggs from the nests of parrots and incubate them under laboratory conditions. Most commercial incubators heat the eggs fairly evenly from top to bottom, thus ignoring the bird’s method of natural incubation, and perhaps reducing the survivability of the hatching chicks.

When incubators are not used, aviculturists sometimes suspend wooden boxes outdoors to use as nests in which to place eggs. In areas where weather can become cold after eggs are laid, it is very important to maintain a deep foundation of nesting material to protect eggs against the cold bottom of the box. If eggs rest against the wooden bottom in extremely cold weather conditions, they can become chilled to a point where the embryo (胚胎) can no longer survive Similarly, these boxes should be protected from direct sunlight to avoid high temperatures that are also fatal to the growing embryo.

Nesting material should be added in sufficient amounts to avoid both extreme temperature situations mentioned above and assure that the eggs have a soft, secure place to rest.

Hatching a theory

Just as dinosaurs characterized the cretaceous (白垩纪的) period, which ended with their extinction 66 million years ago, and mammals made up the Holocene (全新纪), which extends to the present day, many scientists believe we need to designate a new geologic age, called the Anthropocene,     1     reflects the impact of humankind on the planet. That raises the question: What will constitute     2     (noticeable) feature of the Anthropocene in the fossil record?

It’s likely to be chicken bones, according to a study by Carys Bennett, from the U.K.’s University of Leicester, and colleagues     3     (publish) last month in Royal Society Open Science.

Humans eat a lot of chicken, which means a lot of chicken bones are being buried, and many of them are likely to survive in fossilized form. According to Bennett’s paper, 65.8 billion chickens were killed globally in 2016, and     4     22.7 billion live birds await this fate today. The “biomass” of all poultry is 10 times greater than of all wild birds     5     (put) together.

We’re not just eating a lot of poultry; we’ve also put our mark on the birds themselves.     6     chicken consumption started taking off in the 1950s, the size and shape of the species—their skeleton, bone chemistry and genetics—have changed completely from their wild ancestors. The rapid growth of chicken’s leg and breast muscle means that its organs, including the heart and liver, are proportionally smaller. We     7     (shorten) the life span of broiler chickens, which can no longer survive without “intensive human intervention,” the authors write.

Because we engineered the species, and because it has become such a major feature of food consumption, it will     8     (consider) a marker of the Anthropocene, Bennett predicts. “The significance of the post-mid-20^th-century chicken is that it is the first really good example we have     9     what paleontologists (古生物学家) call a new “morphospecies”—that is, a distinctive kind of skeleton that    10     be identified as a fossil—that appeared in the Anthropocene and became hugely abundant pretty well around the world,” she says. “In the future, humans will find and use chickens as a marker of our age.”

9 . Back in 2015 my colleague Adam Frank of the University of Rochester and I were having lunch near Columbia University's campus in New York City. As at Fermi's lunch 65 years earlier, the conversation was about the nature of spacefaring species. And inspired by Fermi's mental calculation, we were trying to craft an investigative strategy that made the fewest possible unsubstantiated assumptions and that could be somehow tested or constrained with real data. At the center of this exercise was the simple thought that waves of exploration or settlement could come and go across the galaxy, with humans happening to come into being in one of the lonely periods.

This idea relates to Hart's original fact: that there is no evidence here on Earth today of extraterrestrial（外星的）explorers. But it goes further by asking whether we can obtain meaningful limits on galactic（星系的）life by constraining the exact length of time over which Earth might have gone unvisited. Perhaps long, long ago extraterrestrial explorers came and went. A number of scientists have, over the years, discussed the possibility of looking for artifacts that might have been left behind after such visitations of our solar system. The necessary scope of a complete search is hard to predict, but the situation on Earth alone turns out to be a bit more manageable. In 2018 another of my colleagues, Gavin Schmidt of NASA's Goddard Institute for Space Studies, together with Adam Frank, produced a critical assessment of whether we could even tell if there had been an earlier industrial civilization on our planet.

As fantastic as it may seem, Schmidt and Frank argue—as do most planetary scientists—that it is actually very easy for time to erase essentially all signs of technological life on Earth. The only real evidence after a million or more years would boil down to isotopic or chemical stratigraphic anomalies—odd features such as synthetic molecules, plastics or radioactive fallout. Fossil remains and other paleontological markers are so rare that they might not tell us anything in this case.

Indeed, modern human urbanization covers only on order of about 1 percent of the planetary surface, providing a very small target area for any paleontologists（古生物学家）in the distant future. Schmidt and Frank also conclude that nobody has yet performed the necessary experiments to look exhaustively for such non-natural signatures on Earth. The bottom line is, if an industrial civilization on the scale of our own had existed a few million years ago, we might not know about it. That absolutely does not mean one existed; it indicates only that the possibility cannot be completely eliminated.

10 . Chimpanzee culture refers to groups' differing behavioral traditions, which are passed on by learning and imitation rather than genes. For example, some chimps in Uganda have learned to use some plants to soak up water, which they can then drink. Those elsewhere don’t do this.

In 2002, Carel van Schaik at the University of Zurich in Switzerland suggested that human interference could destroy this cultural diversity. Now, a decade-long study has found strong evidence that van Schaik was right. A team co-led by Hjalmar Kühl at the German Centre for Integrative Biodiversity Research in Leipzig, Germany tracked 31 cultural behaviors, such as using tree branches to catch termites, a species of ant, in 144 chimpanzee communities across Africa.

The researchers used camera traps to record behaviors, looked for the remains of tools and studied faeces (排泄物) to see if the chimps had eaten things like termites that can be obtained only by using tools.

The team then placed the different communities on a map and overlaid a measure of human disturbance, which combined factors like the density of human population and the amount of infrastructure (基础建设).

In areas with a greater human footprint, the chimps were found to have fewer cultural behaviors. Each behaviour was 88 per cent less likely to occur in these human-dominated landscapes.

“In those places, we find the chimpanzees have suffered a loss in behavioral or cultural diversity,” says study co-leader Ammie Kalan at the Max Planck Institute for Evolutionary Anthropology in Leipzig.

It is thought that the loss of culture comes from older chimps being killed and there being less interaction between groups, so that if one group dies out, their ideas die with them.

“It is a discouraging finding,” says Jill Pruetz ar Texas State University. “Losing some of the behaviors poses a real risk to the chimps because if they stop fishing for termites or cracking nuts, they can no longer access those foods.”