I came across this when looking for a history of biotechnology (in the sense of technology based on biology, including not just work animals but also fermentation, medicine, textiles and dyes, quickset hedges and living bridges, etc). It wasn't that, sadly - instead it's a much more narrow history of genetic engineering. It begins with traditional methods of cross-breeding (so there's a strong focus on cattle, sheep, chickens, and horses) then moves to artificial insemination.

The second half of the book is focused on direct gene editing, ethics, the potential for de-extinction and so forth - at which point I lost interest because it wasn't what I wanted, though not before becoming a bit uncomfortable with how dismissive the author was of resistance to GMO. I'm certainly not an apologist for the fear-mongerers, and the example goals she depicts of increasing animal welfare and improving food security are noble ones. And yet... if we're sawing off the horns of cattle, then is the only solution really to engineer hornless varieties? If people are starving or malnourished, is engineering vitamin-A-rich rice really getting to the root of the cause? Maybe later in the book she addresses these questions - her conversation with school children about mammoths does touch on some nuance - but by this point I was no longer willing to wade through the technical discussion of genes and cells and CRISPR. ( )

Too many stories that I was already familiar with.

> Wolbachia don’t kill the insects that they infect but they do cause fertility problems. When an uninfected female mosquito breeds with an infected male, their offspring don’t survive … it’s difficult to produce only males in a laboratory environment. Because offspring of Wolbachia-infected females survive, the accidental release of Wolbachia-infected females along with males would allow Wolbachia to spread through the population, ruining its potential as a mosquito sterilizer. Second, any reduction of the mosquito population might not last very long if, for example, mosquitoes can easily recolonize from nearby. Finally, Wolbachia are already present in some of the most important disease-vector species, meaning that this approach simply won’t work to control them.

> The self-limiting aspect of the sterility gene works like this: Males that develop from OX5034 eggs have a copy of tTAV on both of their chromosomes. When they mate with wild females, all their offspring inherit one chromosome with tTAV. The female offspring will express tTAV and die, and the males will develop normally. When these males, which have one normal chromosome and one with tTAV, breed with wild females, half their offspring inherit tTAV. Of this half, the females die and the males develop normally. After ten or so generations during each of which the proportion of males in the population with tTAV is reduced by half, tTAV will disappear. Because the number of individuals carrying tTAV reduces in every generation, the population-reducing effect of self-limiting sterility declines over time. This strategy nevertheless has a much longer-term impact than one that requires repeated releases of sterile males.

> The gene-edited moth competed successfully with wild-type diamondback moths, and many fewer caterpillars were produced compared to control fields. Oxitec has also developed self-limiting strains of the fall armyworm, the soybean looper moth, and several other agricultural pests. The self-limiting sterility approach to reducing populations of crop pests could save farmers billions of dollars of losses globally every year while also reducing reliance on chemical pesticides. Intriguingly, it may also help shift the conversation around genetically engineered food, since genetically engineered crop pests (which people don’t eat) could be used in place of genetically engineered, insect-resistant crops with similar gains in crop yield. ( )