Science

Do bacteria mutate randomly, or do they mutate for a purpose? Researchers have been puzzling over this conundrum for over a century.

In 1943, microbiologist Salvador Luria and physicist turned biologist Max Delbrück invented an experiment to argue that bacteria mutated aimlessly. Using their test, other scientists showed that bacteria could acquire resistance to antibiotics they hadn’t encountered before.

The Luria–Delbrück experiment has had a significant effect on science. The findings helped Luria and Delbruck win the Nobel Prize in physiology or medicine in 1969, and students today learn this experiment in biology classrooms. I have been studying this experiment in my work as a biostatistician for over 20 years.

For the first time since the Apollo era, an American spaceship has landed on the Moon: an uncrewed commercial robot, funded by NASA to pave the way for US astronauts to return to Earth's cosmic neighbor later this decade.

Odysseus, built by Houston-based Intuitive Machines, touched down near the lunar south pole Thursday at 2323 GMT, after a nail-biting final descent where flight controllers had to switch to an experimental landing system and took several minutes to establish radio contact with the lander after it came to rest.

Rep. Byron Donalds (R-FL) asserted without evidence that more people had died from wind turbines than nuclear power.

Donalds made the remarks Thursday during a speech at CPAC.

Why do men strongly outperform women at “mindsports” such as chess and bridge? Mindsports mainly use the brain and require skills such as memory, critical thinking, problem solving, strategic planning, mental discipline and judgment. Without physical differences in strength, how do we explain why the top level of such games tends to be dominated by men?

A defining characteristic of bridge, which I study, is that it is always played in partnership. Each game consists of four players divided into two pairs who compete against each other to win tricks. Major bridge events have open and women’s categories, often held concurrently, with very few women playing in the open.

American humorist and writer Mark Twain is believed to have once said, “History doesn’t repeat itself, but it often rhymes.”

I’ve been working as a historian and complexity scientist for the better part of a decade, and I often think about this phrase as I follow different strands of the historical record and notice the same patterns over and over.

My background is in ancient history. As a young researcher, I tried to understand why the Roman Empire became so big and what ultimately led to its downfall. Then, during my doctoral studies, I met the evolutionary biologist turned historian Peter Turchin, and that meeting had a profound impact on my work.

I joined Turchin and a few others who were establishing a new field – a new way to investigate history. It was called cliodynamics after Clio, the ancient Greek muse of history, and dynamics, the study of how complex systems change over time. Cliodynamics marshals scientific and statistical tools to better understand the past.

The aim is to treat history as a “natural” science, using statistical methods, computational simulations and other tools adapted from evolutionary theory, physics and complexity science to understand why things happened the way that they did.

Mosaic representing the Greek muse Clio from the Severian period, coming from the villa located near the Baccano woods, and exhibited at the Palazzo Massimo alle Terme in Rome. Jean-PolGRANDMONT/Wikimedia Commons, CC BY

By turning historical knowledge into scientific “data”, we can run analyses and test hypotheses about historical processes, just like any other science.

The databank of history

Since 2011, my colleagues and I have been compiling an enormous amount of information about the past and storing it in a unique collection called the Seshat: Global History Databank. Seshat involves the contribution of over 100 researchers from around the world.

We create structured, analysable information by surveying the huge amount of scholarship available about the past. For instance, we can record a society’s population as a number, or answer questions about whether something was present or absent. Like, did a society have professional bureaucrats? Or, did it maintain public irrigation works?

These questions get turned into numerical data – a present can become a “1” and absent a “0” – in a way that allows us to examine these data points with a host of analytical tools. Critically, we always combine this “hard” quantitative data with more qualitative descriptions, explaining why the answers were given, providing nuance and marking uncertainty when the research is unclear, and citing relevant published literature.

We’re focused on gathering as many examples of past crises as we can. These are periods of social unrest that often result in major devastation — things like famine, disease outbreaks, civil wars and even complete collapse.

Our goal is to find out what drove these societies into crisis, and then what factors seem to have determined whether people could course-correct to stave off devastation.

But why? Right now, we are living in an age of polycrisis – a state where social, political, economic, environmental and other systems are not only deeply interrelated, but nearly all of them are under strain or experiencing some kind of disaster or extreme upheaval.

Across large parts of the UK, the native red squirrel has been replaced by the grey squirrel, a North American species. As well as endangering reds, grey squirrels pose a threat to our woodlands because of the damage they cause to trees.

New research from my colleagues and I compared the gut bacteria of red and grey squirrels. We found that differences between the two may explain their competition and red squirrel decline, as well as why grey squirrels are so destructive to woodland.

Nina is a Japanese macaque, one of the red-faced monkeys famous for sitting in hot springs in Japan. Nina lives wild in the forest, but most days, along with her group, she visits the Awajishima Monkey Center to eat the food people provide for the monkeys.

Nina was born without hands, an unusually common occurrence in this group of macaques. While no one knows for sure why these malformations of the limbs and digits occur, many researchers have suggested a potential link to pesticides or other environmental contaminants.

An Alabama university temporarily halted in-vitro fertilization (IVF) treatments on Wednesday after the high court in the southern US state ruled that frozen embryos outside the womb are children.

The University of Alabama at Birmingham (UAB) said it had paused IVF treatments "as it evaluates the Alabama Supreme Court's decision that a cryopreserved embryo is a human being."

Baleen whales have evolved a special voice box to help them to sing underwater -- but this could also make them uniquely vulnerable to being drowned out by human noise pollution, according to new research published Wednesday.

Complex whale melodies, first recorded some 50 years ago, are known to play a key role in the social and reproductive communication of these massive marine mammals.

Exercise has long been recognized by clinicians, scientists and public health officials as an important way to maintain health throughout a person’s lifespan. It improves overall fitness, helps build strong muscles and bones, reduces the risk of chronic disease, improves mood and slows physical decline.

Exercise can also significantly reduce the risk of developing conditions that negatively affect heart heath, such as high blood pressure, high cholesterol and obesity. But large amounts of exercise throughout life may also harm the heart, leading to the development of a condition called athletic heart.