As states loosen social distancing rules, more people are venturing out. This led to a question among our editors: In this next phase of the pandemic, how much will masks help mitigate spread of the coronavirus? It turns out a group of researchers from varied backgrounds had just done a review of the literature and fell strongly on the side of widespread face covering.

Also this week: What paleontologists were able to learn by studying fossilized footprints in Tanzania and the story of researchers trying to continue long-term field research despite today’s constraints.

Martin La Monica

Deputy Editor

Evidence is growing that when masks are worn by nearly everyone, it can slow coronavirus transmission. AP Photo/Rick Bowmer

Masks help stop the spread of coronavirus – the science is simple and I’m one of 100 experts urging governors to require public mask-wearing

Jeremy Howard, University of San Francisco

Recommendations around mask usage are confusing. The science isn't. Evidence shows that masks are extremely effective to slow the coronavirus and may be the best tool available right now to fight it.

Footprints, preserved in solidified ash, hint at human behavior from as long as 19,000 years ago. Cynthia Liutkus-Pierce

Prehistoric human footprints reveal a rare snapshot of ancient human group behavior

William E.H. Harcourt-Smith, Lehman College, CUNY; Briana Pobiner, Smithsonian Institution

The footprints of over 20 different prehistoric people, pressed into volcanic ash thousands of years ago in Tanzania, show possible evidence for sexual division of labor in this ancient community.

Collecting data on invasive plants, Santa Monica Mountains National Recreation Area, California. Connar L'Ecuyer/NPS

COVID-19 is eroding scientific field work – and our knowledge of how the world is changing

Richard B. Primack, Boston University; Casey Setash, Colorado State University

The COVID-19 pandemic is interrupting scientific field work across North America, leaving blank spots in important data sets and making it harder to track ecological change.

Other good finds