Plus: Scientists make a surprisingly small discovery that may explain what puts the world’s strongest humans over the top.

Also: Cryptocurrency invades the U.S. election; back-to-school is on hold in fire-stricken Jasper, Alberta; advocates say it’s still too easy for abusers to access firearms; and we remember Phil Lewis, whose life in 1980s London during the AIDS crisis helped inspire the TV show It’s A Sin.