The Conversation

The US economy produced about $21.7 trillion in goods and services in 2019 – but what does GDP really mean?

Written by Dan Sichel, Professor of Economics, Wellesley College

It's just dollars and cents.mrfiza/Getty Images

Editor’s note: The Bureau of Economic Analysis reported on Jan. 30 that U.S. Gross Domestic Product climbed to an estimated nominal value of US$21.7 trillion. But what does that really mean? We asked Dan Sichel, an economist at Wellesley College, to explain what goes into that massive number...

Is the coronavirus outbreak as bad as SARS or the 2009 influenza pandemic? A biologist explains the clues

Written by Maciej F. Boni, Associate Professor of Biology, Pennsylvania State University

A man wearing a face mask prays at Erawan shrine in Bangkok, Thailand, Jan. 29, 2020. Thailand has five reported cases of coronavirus.AP Photo/Gemunu Amarasinghe

As the new coronavirus continues to cross international borders, the two key questions on public health officials’ minds are: ‘How deadly is it?’ and ‘Can it be...

What is a super spreader? An infectious disease expert explains

Written by Elizabeth McGraw, Professor of Entomology and Director of the Center for Infectious Disease Dynamics, Pennsylvania State University

Whether by biology or behavior, some people in the crowd will transmit coronavirus to more than the average number of others.AP Photo/Kin Cheung

As the emerging Wuhan coronavirus outbreak dominates the daily news, you might be wondering just how the pathogen is working its way around the world. This virus travels from place to place by infecting one...

Harvey Weinstein's 'false memory' defense is not backed by science

Written by Anne P. DePrince, Professor of Psychology, University of Denver

Harvey Weinstein leaves for the day during his trial on charges of rape and sexual assault, in New York, Jan. 28, 2020. AP Photo/Craig Ruttle

Much like the defense of Bill Cosby, media mogul Harvey Weinstein’s defense team says they’ll bring up “false memories” during his trial on multiple charges of sexual assault. In...

How do I know if I might have coronavirus? 5 questions answered

Written by Catharine Paules, Associate Professor of Medicine, Infectious Diseases, Pennsylvania State University

Students line up to sanitize their hands to avoid the contact of coronavirus in Phnom Penh, Cambodia, Jan. 28, 2020.AP Photo/Heng Sinith

Editor’s note: The new coronavirus, 2019 n-CoV, continues to spread in China, and cases are being diagnosed in many other countries, including the U.S. In some of those countries, including Germany and...

Modern tomatoes are very different from their wild ancestors – and we found missing links in their evolution

Written by Hamid Razifard, Postdoctoral Researcher in Biology, University of Massachusetts Amherst

Tomatoes' ancestors looked very different. Foxys Forest Manufacture/Shutterstock

The Research Brief is a short take on interesting academic work.

The Big Idea: The tomato’s path from wild plant to household staple is much more complex than researchers have long thought. For many years, scientists believed that humans domesticated the tomato in...

Union gunboats didn't just attack rebel military sites – they went after civilian property, too

Written by Robert Gudmestad, Professor and Chair of History Department, Colorado State University

The USS Cairo pulls up to the banks of the Mississippi River in 1862.U.S. Naval History and Heritage Command

During the American Civil War, huge metal monsters roamed the Mississippi River. Called ironclads, these boats were about 50 yards long, carried 75 tons of armor on their hulls and decks, sported up to 13 guns, and had crews numbering up to...

4 myths the Trump team promoted about Andrew Johnson

Written by Paul Harvey, Professor of American History, University of Colorado Colorado Springs

The U.S. House of Representatives brought 11 articles of impeachment against Andrew Johnson.Photo by The Print Collector/Print Collector/Getty Images

The claims: Andrew Johnson then, like Donald Trump now, was unjustly impeached by a group of radicals in the House of Representatives.

Fortunately – so the claim continues – enough honest...

Preventing genocide in Myanmar: Court order tries to protect Rohingya Muslims where politics has failed

Written by Hurst Hannum, Professor of International Law, Tufts University

The Myanmar military's years-long campaign against the Rohingya Muslims left hundreds of villages a smoldering pile of debris. Warpait village, Rakhine State, Oct.14, 2016.Ye Aung Thu/AFP via Getty Images)

Myanmar has been ordered by the International Court of Justice to take “provisional measures” to protect the Rohingya, an ethnic...

Brain organoids help neuroscientists understand brain development, but aren't perfect matches for real brains

Written by Madeline Andrews, Postdoctoral Scholar of Regeneration Medicine, University of California, San Francisco

Just a few millimeters across, organoids are clumps of cells that resemble the brain. Madeline Andrews, Arnold Kriegstein's lab, UCSF, CC BY-ND

What was going on with our brain organoids?

As neuroscientists, we use these three-dimensional clusters of cells grown in petri dishes to learn more about how the human brain works. Researchers culture...