【推荐1】It may come as a surprise that human beings are not alone in inventing vaccine. Work published in the Journal of Experimental Biology by Gyan Harwood of the University of Illinois, confirms that honeybees got there first.

The scientists discovered in 2015, that queen bees vaccinate their eggs before they are laid. The vaccine is some pieces of proteins from diseasing-causing pathogens. They act as antigens which cause a protective immune response. But it raised the question: how the queen received her antigen? For she is fed purely on royal jelly, a thing produced by nurse bees. Meanwhile, work bees fly out looking for food to feed nurse bees. Dr Harwood therefore wondered if the nurses received the pathogens while eating the food from the outside, and then got them into their royal jelly, as the queen’s food at last.

To find the answer, Dr Harwood collected 150 nurse bees and divided them among six queenless mini boxes equipped with baby bees to look after. They fed the nurses on sugar-water, and for three of the boxes he placed Paenibacillus, a bacterium causing young bees’ death.

In this case, Dr Harwood marked the dead bacteria with a color, to make their footprint easy to track. And, sure enough, microscope confirmed that pieces of Paenibacillus were getting into royal jelly produced by those bees which had been fed with sugar-water, which is thought to help bee develop immune system.

All told, these findings suggest that nurse bees are indeed, via their royal jelly, passing antigens on to the queen for transferring into her eggs. They also mean, because baby bees, too, receive royal jelly for the first few days after the birth, that the nurses are vaccinating the baby bees as well. Each baby bee is therefore being vaccinated twice.

【推荐2】Some big scientific discoveries aren’t actually discovered but borrowed. That’s what happened when scientists discovered proteins from an unlikely lender: green algae(绿藻), whose cells are decorated with proteins that can sense light.

The light-sensing protein promised the power to control neurons(神经元)by providing a way to turn them on and off. Such ability, first noticed in 2002, quickly caught the attention of brain scientists: Nerve cells which were genetically engineered to produce such proteins become light-controlled. A flash of light could cause a quiet neuron to send signals or force an active neuron to fall silent. “This is the light sensor that we needed,” says Zhuo-Hua Pan, a scientist searching for a way to control vision cells in mice’s eyes. The method is now called optogenetics (光遗传学).

In Pan’s lab, light-responsive proteins restored vision in mice with damaged eyesight, a finding that has now led to a medical test on people. Optogenetics’ promise wasn’t clear in early days, as scientists were first learning how to use these proteins in neurons. “At that time, no one expected that this optogenetic work would have such a huge impact,” Pan says.

The algae’s light sensors have been adopted for use in countless brain research fields. Talia, another scientist, uses optogenetics to study connections between cells in the mouse brain. The method allows her to comb the relationships between cells that produce and respond to dopamine(多巴胺), which might help uncover details about motivation and learning.

So far, optogenetics research has taken place mostly in mice. But findings into more complex brains like human brain may soon be confirmed. “We are definitely on the tip of uncovering some fascinating principles of the human brain, such as how the brain transforms signals from the eyes into perceptions,” says Yasmine of Columbia University.

No matter what happens next in this swiftly moving field, one thing is certain: Brain scientists will be forever in the algae’s debt.

【推荐1】Houses covered in ivy are an attractive sight to see. But many gardeners fear that ivy causes major structural damage to buildings and long to remove it whenever they can, right? Not so, says James Wong, a botanist and science writer.

“I am always surprised by how often gardening can be so driven by fear.” he says. “The thinking behind this is that climbers harm brickwork and can cause structural damage to buildings.” But few fears are based on any scientific evidence. And frequently, the exact opposite is true.

In a 2020 study from the Royal Horticultural Society, climbing plants like ivy were found to have a protective effect on model brick buildings constructed for the experiment. The shade by the plants’ leaves cooled the surface of the buildings in summer by as much as 5.7°C. What’s more, ivy didn’t significantly raise humidity levels (湿度) －rather, it helped stabilize them, minimizing the damage to the buildings’ surfaces. The living coating also lowered summer temperatures inside the buildings by up to 7.2°C and reduced heating bills by as much as 20 percent in winter.

What about real-world, well-used buildings, whose outside may have experienced centuries of environmental damage? Another study from 2011 found that in five historic buildings across England, bare walls experienced average maximum temperatures 36 percent higher and minimum temperatures 15 percent lower compared with those coated in ivy. The researchers concluded that the living insulation (隔热) provided by ivy would “reduce the likelihood of frost and salt damage to the building materials, thus contributing to their conservation”. They also found in another study that the leaves’ ability to trap pollution could reduce the damage to historical walls.

Imagine if there was a new material that could cool cities and cut energy bills. The truth is that we have had this miracle material all along, but rather than appreciating it, we have spent huge amounts of time worrying about how to get rid of it.