A nearly six-hour grilling of TikTok’s CEO by lawmakers brought the platform’s 150 million U.S. users no closer to an answer as to whether the app will be wiped from their devices. Shou Zi Chew’s testimony Thursday came at a crucial time for the company, which has 150 million American users but is under increasing pressure from U.S. officials concerned about data security and user safety. TikTok and its Chinese parent company, ByteDance, have been swept up in a wider geopolitical battle between Beijing and Washington over trade and technology. Chew, a 40-year-old Singapore native, made a rare public appearance to counter the volley of allegations that TikTok has been facing.

New research suggests our capacity to care about others might have very ancient roots. Scientists are usually reluctant to attribute humanlike feelings to animals, but it’s generally accepted that many animals have moods, including fish. A study published Thursday shows that fish can detect fear in other fish, and then become afraid too – and that this ability is regulated by oxytocin, the same brain chemical that underlies the capacity for empathy in humans. This raises the possibility that our ability to care for others was deep-rooted in prehistoric animals, before fish and mammals like us diverged on the tree of life.

The Federal Reserve is getting some unwanted help in its drive to slow the U.S. economy and defeat the worst bout of inflation in four decades: a cutback in bank lending. The upheaval in the financial system that’s followed the collapse of two major U.S. banks is raising the likelihood that lending standards will become sharply more restrictive. Fewer loans would mean less spending by consumers and businesses. That, in turn, would make it harder for companies to raise prices, thereby reducing inflationary pressures. Some economists worry, though, that the slowdown might prove so severe as to send the economy sliding into a painful recession.

TikTok is ramping up a public relations campaign to fend off the possibility of a nationwide ban by the Biden administration. And it’s bringing some unconventional advocates to help: online influencers. Dozens of TikTok creators came to Capitol Hill on Wednesday to lobby in favor of the platform the day before lawmakers are slated to grill the company’s chief executive about concerns over user data falling into the hands of the Chinese government. TikTok’s CEO plans to tell Congress on Thursday that the video-sharing app is committed to user safety, data protection and security, and keeping the platform free from Chinese government influence. Shou Zi Chew is due to answer questions from lawmakers concerned about the social media platform’s effects on its young user base.

The Federal Reserve extended its year-long fight against high inflation by raising its key interest rate by a quarter-point despite concerns that higher borrowing rates could worsen the turmoil that has gripped the banking system. Fed Chair Jerome Powell sought to reassure Americans that it is safe to leave money in their banks, two weeks after a rush of depositors pulled funds from Silicon Valley Bank, which collapsed in the second-biggest bank failure in U.S. history. Signature Bank fell soon afterward. “We have the tools to protect depositors when there’s a threat of serious harm to the economy or to the financial system,” Powell said. “Depositors should assume that their deposits are safe.”

The Biden administration plans to break up the network that runs the nation's organ transplant system. The United Network for Organ Sharing has a government contract to oversee how organs are retrieved and distributed and to run the massive computer system that matches patients and organs. While transplants are steadily increasing, critics say the country could do better. Wednesday, the government said it planned to divide transplant oversight duties so that more than one company does the job. Exactly how that will work isn't clear. UNOS says it has the needed expertise and has begun its own improvements.

There's a pesky problem in a wide stretch of the Atlantic Ocean that's likely to wash up on some beaches later this year: Seaweed. Lots of it. The Great Atlantic Sargassum Belt is a biomass of thick, brown seaweed in patches scattered across a 5,000-mile belt of the Sargasso Sea well off the southeastern U.S. coastline. The sargassum is expected to wash ashore in coming months on some Florida beaches, in the Caribbean islands and Mexico's Yucatán Peninsula. Sargassum blooms aren't new, but this year's appearance in February was an early start for such a large algae mass. On shore, sargassum is a nuisance — carpeting beaches and releasing a pungent smell as it decays. For hotels and resorts, clearing the stuff off beaches can amount to a round-the-clock operation.