Facebook shares have lost $55 billion in market value over the past two days and that pain is spreading to rivals like Twitter as investors fear government crackdowns are coming, which could curtail the data collection that has fueled the sectors’ revenue growth.

Amazon is pushing merchants on its website to sell into other countries to better compete with rival marketplaces run by eBay and Alibaba. Aleksandra Michalska reports.

After a report in The Times, the National Institutes of Health will examine whether health officials violated government policy by soliciting donations to fund a study of moderate drinking.

Despite warnings from experts, older people are using more anti-anxiety and sleep medications, putting them at risk of serious side effects and even overdoses.

The geneticist at Harvard Medical School has retrieved DNA from more than 900 ancient people. His findings trace the prehistoric migrations of our species.

A further drop in shares of Facebook capped gains in the S&P 500 and Nasdaq Tuesday. Fred Katayama reports.