Have you ever noticed an ant in your home, only to find that a week later the whole group has moved in? The traps you set up catch only a few of these ants, but soon, the rest of the group has mysteriously disappeared. Now a study published in the journal Cell explores how certain danger-signaling pheromones(信息激素)—the scent markers ants give off to communicate with each other — activate a specific part of the ants’ brains and can change the behavior of the whole nest.

This research suggests that ants have their own kind of communication center in their brains, similar to humans. This center can interpret alarm pheromones, or “danger signals”, from other ants. The researchers used an engineered protein called GCaMP to scan the brain activity of clonal raider ants(克隆蚁) that were exposed to danger signals. GCaMP works by attaching itself to calcium ions (钙离子), which light up with brain activity, and the resulting chemical compound can be seen on high-resolution microscopes adapted to view them.

When performing the scans, the researchers noticed that only a small section of the ants’ brains lit up in response to danger signals, but the ants still showed immediate and complex behaviors in response. These behaviors were named the “panic response” because they involved actions such as fleeing, and transporting their young from the nest toward a safer location.

For the purpose of this study, researchers chose clonal raider ants as a species because they are easy to control. They used ants of one sex within one class and role (female worker ants) to guarantee consistency and therefore make it easier to observe widespread patterns.

Bangladesh's floating gardens, built to grow food during flood seasons, could offer a continuous solution for parts of the world which are likely to suffer from flooding because of climate change, a new study has found.

Bangladesh's floating gardens began hundreds of years ago. The gardens are made from native plants that float in the rivers and operate almost like rafts (筏), rising and filling with the waters. Historically, they were used to continue growing food during rainy seasons when rivers were filled with water.

The farmers layer the plants about three feet deep, creating a version of raised-bed gardens that float in the water. Then, they plant vegetables inside those rafts. As the raft-plants rot away, they release nutrients, which help feed the vegetable plants.

But as climate change affected the volume of water in those rivers, the researchers wanted to understand whether Bangladesh's floating gardens could be a continuous farming practice. They interviewed farming families and found strong evidence that floating gardens provide stability, both in the amount of food available to feed rural populations and in a farming family's income.

They found that farmers typically use hybrid (杂交) seeds, which must be repurchased each year, to grow a diverse range of vegetables in the floating gardens. The gardens are also sensitive to pests, so farmers end up spending some money on both pesticides and fertilizers. But even with those expenses, they found, benefits outweighed costs. One farmer told the research team that he earns up to four times as much money from the gardens as from traditional rice fields.

However, before gaining profits, farmers often take out high-interest loans (贷款) to cover the investment costs of filling the beds and stocking them with plants. Luckily; there are also lower-interest loans from responsible government or non-governmental organizations, which could ease that burden.

Wheat is a main source of food for people across the planet, accounting for a fifth of the calories consumed globally. But, as a result of climate change, scientists believe most parts of the world where the crop is grown will be hit by water shortages by the end of the century. And the U.S. could be among the countries worst affected, the authors of the research published in the journal Science Advances told Newsweek.

If climate change isn’t dealt with, by the year 2100, 60 percent of areas that grow wheat will be hit by water scarcity—up from the current level of 15 percent, according to the international team of scientists.

Co-authors Miroslav Tmka and Song Feng told Newsweek that in their previous research, they had shown climate change may cause soil to become less moist across most mainland U.S. states, including those where wheat is grown. As a result, the U.S. could be “one of the top most affected wheat producers” in terms of the increase in areas affected by severe droughts, they said in a joint statement.

Worryingly, existing research has predicted a 4.0 to 6.5 percent drop in global wheat production per 1 degree Celsius of warming if climate change isn’t eased. And it’s unlikely that wheat can be replaced if water becomes scarce, as it’s not as thirsty as other crops and can do without water for a relatively long period of time.

“If multiple regions are affected by drought at the same time, “it might be difficult to meet the demand even if the trade routes stay open and are not restricted by governmental measures,” warned Fengand Trnka. However, he said: “Studies show that if we continuously improve the sustainability and technologies in the coming decades and allow for international trade, we may overcome the negative impacts of climate change.”