1 . While DNA from animal bones or teeth can cast light on an individual species, environmental DNA enabled scientists to build a picture of a whole ecosystem.

A core of ice age sediment (沉积物) from northern Greenland has yielded the world’s oldest sequences of DNA. The 2 million-year-old DNA samples revealed the now largely lifeless polar region was once home to rich plant and animal life — including elephant-like mammals known as mastodons (乳齿象), reindeer, hares, lemmings, geese, birch trees and poplars, according to new research published in the journal Nature on Wednesday.

The finding is the work of scientists in Denmark who were able to detect and restore environmental DNA — genetic material drop into the environment by all living organisms — in tiny amounts of sediment taken from the Copenhagen Formation, in the mouth of a strait in the Arctic Ocean in Greenland’s northernmost point, during a 2006 expedition.

They then compared the DNA pieces with libraries of DNA collected from both extinct and living animals, plants and microorganisms. The genetic material revealed dozens of other plants and creatures that had not been previously detected at the site based on what’s known from fossils and pollen records.

“The first thing that blew our mind when we’re looking at this data is obviously this mastodon and the presence of it that far north, which is quite far north of what we knew as its natural range,” said study co-author Mikkel Pedersen.

The mix of temperate (温带) and Arctic trees and animals suggested a previously unknown type of ecosystem that has no modern equivalent — one that could act as a genetic road map for how different species might adapt to a warmer climate, the researchers found.

Love Dalen, a professor at the Centre for Palaeogenetics at Stockholm University, said the finding “pushed the envelope” for the field of ancient DNA. “Also, the findings that several temperate species (such as relatives of spruce and mastodon) lived at such high latitudes are exceptionally interesting,” he added.

Further study of environmental DNA from this time period could help scientists understand how various organisms might adapt to climate change. “It’s a climate that we expect to face on Earth due to global warming and it gives us some idea of how nature will respond to increasing temperatures,” he explained.

3 . Family Link has lots of advantages that may be favored by parents. Inside the app, you can create Google accounts for your children, sharing information like their names and birth dates.     1    , the device immediately requires you to log in and install the Family Link app onto the device so it can be monitored.

    2    On the parent’s phone, by tapping on the child’s account profile you can follow a child’s location. You can also approve or reject apps that a child is trying to download. So if you’re worried about an addictive game, simply block the apps.

Parents can also use Family Link to create restrictions for how children browse the web. You can turn on a filter (过滤器) that blocks bad websites, though Google acknowledges the filter is imperfect and some unpleasant sites may get past it.     3    , you can also require the child to get permission for each site visited, blocking the ones you disapprove of.

    4    , which can be used to set limits for how long a child can use a phone each day. For instance, you could give the child three hours on weekdays. You can also schedule regular bedtime hours that lockdown the device at specific times.

Caroline Knorr, the parenting editor of Common Sense Media, which evaluates content and products for families, applauded the screen time feature, noting the difficulty of getting children to put down their phones.     5    “It’s not a set-it-and-forget-it thing where parents think,” she said. “We’re all still learning this technology, and life is very unpredictable.”

5 . In late May, America announced a plan to greatly expand offshore wind energy installations (安装) along the Pacific, Atlantic, and Gulf coasts, with the ultimate goal of adding clean energy enough to power 10 million homes by 2030. But is it realistic?

Those standing on the side of answering yes to this question understand that innovation (创新) is the key to pulling off the project. Unlike the open plains and rounded hills that traditionally host wind turbines, analyzing the seafloor situation for proper placement isn’t a simple exercise. With only 20% of the ocean seafloor mapped, we basically know more about the surface of Mars than we do Earth’s hidden depths.

Startup Bedrock is aiming to help shine a light on this problem by detecting the seas with its new electric self-driven underwater vehicles (AUV). Traditional ocean mapping techniques are ship-based, usually limited to the surface. Thus, traditional sea surveys can take up to a year to collect and process data. But Bedrock’s AUVs send data to a cloud-based platform called Mosaic that allows computers to start working with the results nearly right away and from anywhere in the world.

While using AUVs to map the seafloor helps improve our understanding of Earth’s oceans, Bedrock was careful that this do not come at the expense of sea life. The company uses smaller sensors that are close to the seafloor and operate in sound frequencies safe for animals. In addition, the AUVs only travel at roughly 2. 3 mph to 3. 45 mph, which reduces the chance of animal or environmental damage as they are moving.

Beyond the offshore wind industry, Bedrock is also exploring other ways its AUVs might benefit other marine-based efforts. “Currently our AUV surveys are designed for offshore wind projects, cable laying, nearshore environmental mapping for coastal management,” says Bedrock CEO and co-founder DiMare. “In the future, we’re also capable of serving new markets, helping to make ambitious government goals a reality.”

6 . According to the Solar Energy Industry Association, the number of solar panels installed(安装)has grown rapidly in the past decade, and it has to grow even faster to meet climate goals. But all of that growth will take up a lot of space, and though more and more people accept the concept of solar energy, few like large solar panels to be installed near them.

Solar developers want to put up panels as quickly and cheaply as possible, so they haven’t given much thought to what they put under them. Often, they’ll end up filling the area with small stones and using chemicals to control weeds. The result is that many communities, especially in farming regions, see solar farms as destroyers of the soil.

“Solar projects need to be good neighbors,” says Jordan Macknick, the head of the Innovative Site Preparation and Impact Reductions on the Environment(InSPIRE)project. “They need to be protectors of the land and contribute to the agricultural economy.” InSPIRE is investigating practical approaches to “low-impact” solar development, which focuses on establishing and operating solar farms in a way that is kinder to the land. One of the easiest low-impact solar strategies is providing habitat for pollinators(传粉昆虫).

Habitat loss, pesticide use, and climate change have caused dramatic declines in pollinator populations over the past couple of decades, which has damaged the U.S. agricultural economy. Over 28 states have passed laws related to pollinator habitat protection and pesticide use. Conservation organizations put out pollinator-friendliness guidelines for home gardens, businesses, schools, cities—and now there are guidelines for solar farms.

Over the past few years, many solar farm developers have transformed the space under their solar panels into a shelter for various kinds of pollinators, resulting in soil improvement and carbon reduction. “These pollinator-friendly solar farms can have a valuable impact on everything that’s going on in the landscape,” says Macknick.

8 . About two years ago, several lunar missions showed that some lunar soil contains minute amounts of water molecules. But where did water on the moon come from? Answering that question can help us understand the moon’s history and evolution, but also allow future engineers to potentially tap into this resource when building a sustainable moon base.

Chinese scientists have discovered that minerals in lunar soil might have got that substance   (物质) critical for life from solar wind bombarding (轰炸) the moon’s surface with hydrogen ions (氢离子), according to a study published in the journal Nature Communication on Saturday.

In a previous study, published in June, Chinese scientists concluded that most water found on the moon may have originated in its interior. That study, like the new one, was conducted on lunar samples from China’s Chang’e-5 mission in 2020.

The study in June found that lunar soil had around 30 parts per million of water content in the form of hydroxyl (羟基), a close chemical relative of water. However, lunar minerals may contain water content of up to 179 ppm. One ppm of water would yield (产生) around 1 gram of water per metric ton (公吨) of soil.

The latest study essentially confirmed the estimates from the previous research, and those lunar minerals could contain even more water. Moreover, the new study identified solar wind as a key mechanism for the existence of water on the moon’s surface.

The study found that the solar wind resulted at least 170 ppm of water content in lunar samples gathered by the Chang’e-5 mission. Lunar minerals such as pyroxene, plagioclase, and olivine are likely the main reservoirs (水库) of solar wind-derived water.

“This study has important implications for understanding the evolution of water on the lunar surface and evaluating the contribution of solar wind protons (质子) to the water reservoirs of the lunar surface, ”the researchers said.

Lunar samples collected during the Chang’e-5 mission may hold the keys to answering these questions, since they are much younger than the ones collected by US and Soviet moon missions. So, the water content in the Chinese samples has had less time to be influenced by other factors, making these samples ideal for studying the moon’s water.