In 1851, a German doctor named Carl Reinhold August Wunderlich took the temperatures of some 25,000 patients in the city of Leipzig and concluded that the average human body temperature sits at 37 degrees Celsius, or 98.6 degrees Fahrenheit. Though variations are known to exist from person to person, Wunderlich’s standard remains a benchmark for medical professionals today. But a new study published in eLife suggests that in the United States, at least, average temperatures are going down—a trend that can be observed in medical records spanning more than 150 years.⁠ ⁠ Previous research indicated that Wunderlich’s average may have run a little high. In a 1992 study of 148 patients, for instance, scientists at the University of Maryland measured an average temperature of 36.8 degrees Celsius, or 98.2 degrees Fahrenheit. More recently, a 2017 study of around 35,000 British patients found that the mean oral temperature clocked in at 36.6 degrees Celsius, or 97.9 degrees Fahrenheit. Some ex...