INVESTIGATE

Kissing Has Existed for at Least 16 Million Years, Scientists Say

When Humans Learned to Live Everywhere

In Their Final Moments, a Pompeii Family Fought to Survive

The Best Way to Drop an Egg

How Trump’s Cuts Are Stifling L.G.B.T.Q. Health Research

Volcanic Eruption in Deep Ocean Ridge Is Witnessed by Scientists for First Time

The Very Territorial Caterpillar

Scientists Reveal the Hairy Truth About Giant Ground Sloths

Auroras Are Spotted on Neptune for the First Time, and Lead to a New Mystery

Videos Show Narwhals Using Their Tusks to Play With Their Food

Science, Politics and Anxiety Mix at Rally Under Lincoln Memorial

Humans Have Been Perfecting Avocados for 7,500 Years

A Boneyard Along the Thames River Reveals London’s Ancient Burials

The Gene That Made Mice Squeak Strangely

Louis Pasteur’s Relentless Hunt for Germs Floating in the Air

Lasers, Waffle Fries and the Secrets in Pterosaurs’ Tails

Grand Canyons on the Moon Were Made in a Matter of Minutes

Could the Bird Flu Become Airborne?

Snakeskin: It’s Fashionable, and It Scares Predators Away From Bird Nests

When They Hear Plants Crying, Moths Make a Decision