This book would have done better with some better explanation of experimental limitation and waaay less sexism. Throughout the entire book, I got dizzy listening to the author stating how much more superior his wife's navigational skills are to his, only for him to quickly insert "but actually, men outperform women on average, it's science".
Was the book interesting? Yes in the first half, especially when laying down the foundations of navigational tasks in the brain. And the way the book started I thought the author will dare to offer some potential scientific explanations for why some people got spectacularly lost (and some got to tell the tale).
However, what followed in the second half was a thick soup of research presented as fact, with insufficient discussions about controls and experimental design. The author tells us about how men's superior navigational skills are due to the hunter gatherer evolution of our species. A paragraph later he gives voice to a researcher who disproves it. He later talks about the Mozart effect, presenting it as fact. He then says later that the effect is unreproducible. He's organized parts of this book the same way his brain takes him down a path: he's convinced this is the right path, and then just turns on a different path equally convinced that is the correct one. There is no discussion on limitations for these theories. There is no critical thinking. And that's the biggest problem with this book. Here's an example: We are presented a theory on why Homo sapiens overtook the Neanderthal species, because a scientist experimented with brain organoids in a dish and saw that when he mutates a gene the organoids look different. So, did you repeat the experiment in a mouse? Try to do a proteomics or genomics experiment to see how it knocking the gene in and out affects the protein interactome, or transcriptome? Did they try to put it in a mouse, or a different animal? Just this week I read another article about a critical gene that explains our ability to outlive the Neanderthals, so which one was the real CRITICAL gene? (the latter article at least included experiments in mice). The author just regurgitates information, makes no attempt to critically analyze it, but does summarize it.
I mentioned the sexism: I really want to see what these experiments will show in a few decades. It's like we never learn how our implicit sexism impacts not only abilities in the two sexes (no mention of the spectrum in the book), but also our ability to interpret those results. You may remember an experiment in the 90s where young boys and girls were put in an fMRI while reading and it was observed that girls activate more regions in the brain while reading. Conclusion: girls' brain are having more difficulty reading and that's why they require that more regions to be active while reading. Reality, when more research was done: , those extra regions were likely responsible for decoding metaphors and symbolic meanings in the text and boys activated the same regions a bit later in their development. Girls weren't dumber, they were actually developing superior reading skills faster than boys.
This book is rife with examples of implicit bias being either left unaddressed, or not properly controlled. Did you know than only ~2% of London cabbies are women? (The author just drops that in there, no explanation). Did you also know that most western societies are more likely to encourage men to become drivers and women to become nurses? Well that's not even hinted at in the book. What about controlled experiments? Research suggests that in countries where societal norms encourage equality between the sexes navigational skills are almost identical between men and women. The author declares however some countries as completely egalitarian, no traces of implicit bias left over. His reasoning? Not explained. A bit later we discuss about another test where women are outperformed by men even in these egalitarian countries. The gap is largest the author says in egalitarian societies. Larger than between women in egalitarian societies and women in societies that keep them locked in the home. How is that possible? What does large mean? What's the percentage? What's the average/median/mode of distribution? What's the sample size in different countries? Are we talking a difference between 2% and 4%? No clue! And I got really angry reading about the author's inability to understand that even egalitarian societies are still shedding implicit bias; hell, I grew up in countries where women were heralded as equal and encouraged to enter STEM fields, and were the majority of professors in the university...and I still heard our 2 male profs telling us that actually men are better, but women work harder. What?!?!?!? Over and over again I heard this, as well as comments about manliness being impaired for those entering nursing, and professional driving being a manly job. It's absurd, I could write an entire thesis on how many gaps the author allowed in his logic, but I don't have the time or energy. Here we are again, with another poorly written science book heralding the inferiority of women. Let's see how we'll look at this in a few decades, when more research has come in.
And let me end by why I doubt women can be genetically selected to be inferior 3D rotaters--the same genes that allow men to be good at 3D rotating and navigation ARE FOUND IN WOMEN TOO (and women have more genes than men on average--again, there is a discussion to be had about intersex, but it's already a long review). Some people will jump to the conclusion that perhaps its epigenetics that's to blame, perhaps maternal/paternal methylation impacts how we activate those genes: that can't be it, since it's clear that mothers with superior/inferior navigational skills pass their genes to sons who end up being just like them and vice-versa (fathers to daughters). Perhaps estrogen/testosterone levels have something to do with it? Why would it? Estrogen and testosterone influence behavior, specifically mating, but then it would mean that pre-puberty experiments can be run to see if there is a difference between the genders before hormones kick in; or if there is an inversion of skills in trans people. Until reliable experiments are performed with these controls, I remain unconvinced that testosterone and estrogen explain everything from favorite foods to choice of mate, to ability to do math. It just doesn't make sense, in a species where brain plasticity has enabled us to evolve into the top predator and manipulator of our ecosystem, to have so much depend on gender and gonads. But again, experiments can be performed and maybe they'll show indeed that there is epigenetic regulation that impacts navigation in genders. Until then, could we stop acting like erudite sexists when writing books addressed to the general public? As a woman in STEM with a mother in STEM (and said mother has far superior math and navigational abilities compared to my father), I'm getting very tired of this.