This week’s Top Ten debunks claims about the first Europeans, examines dopamine’s real benefits, investigates microplastics in our brains ... and discovers how long it takes to boil the perfect egg.

DANUBIAN ROUTE OF YAMNAYA CULTURE PROJECT, NATIONAL SCIENCE CENTER, POLAND 

PHOTOGRAPH SAMUNELLA, SCIENCE PHOTO LIBRARY 

A startling study has found microplastics and nanoplastics accumulate at higher levels in the human brain than in the liver and kidneys—and at significantly higher concentrations over the last eight years. There are particularly alarming findings for people with dementia.

Related:

- In a first, microplastic particles have been linked to heart disease 

- What are the signs of dementia—and why is it so hard to diagnose? 

PHOTOGRAPH BY JACK DYKINGA

The desert’s most tenacious bird: This owl chick is learning to fly in its new home. Tiny underground apartments are being built to save it and other owls. Where? 

A. Arizona
B. Atacama, Chile
C. Sonora, Mexico
D. None of the above 

Today’s Soundtrack: A Bar Song (Tipsy), Shaboozey 

Today’s newsletter was edited and curated by David Beard and produced by Amanda Williams-Bryant. Let us know if you have suggestions, and/or sign up here to get our upcoming Photo of the Week!