Guiness Book of World Records lists: Marilyn vos Savant (a woman) as having the highest IQ on record
I agree with the Time magazine article, it depends on how people apply themselves, because more neurons form (and more connections between them form) based on increased brain use. So one's social environmental is key.
Polgar raised his two daughters to be chess grandmasters and believed they could become chess grandmasters, and they did. One of his daughters is in the top ten among the world's greatest players, and has beaten world champions in individual tournament games.
Also, for centuries men prided themselves on having generally larger craniums and larger brains:
"In overall size, men's brains average 15 percent larger than women's - about two times the average difference in body size. Male supremacists, check your smugness. 'Size in and of itself is not intelligence,' says Lucia Jacobs, Ph.D., a psychologist and neuroscientist at the University of California at Berkeley. 'You can't say a cow is smarter than a mouse. It doesn't scale like that.' Much more important is the number of neurons and their structural organization. 'If I had to pick a brain, I think I'd take a female brain,' says Jacobs. 'It's symmetrical, multitasking and more resistant to stroke because language ability is stored in both hemispheres. The female brain is like a Swiss army knife - whereas males get stuck with one big blade.'"
Even if there is a genetic component to some people being born with the propensity for growing up a little more intelligent than others (I am speaking of both males and females carrying such genes), it doesn't seem that such people are very lucky at begetting children. As if God had taken care so as not to allow wisdom to spread too much among human beings.
(Based on something Erasmus once pointed out in his book, In Praise of Folly)