Book review of Helen Pilcher

Helen Pilcher:
"Life Changing" (2020)
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We are surrounded by domesticated species. The dog is a wolf that humans genetically modified over the course of about 30,000 years by selecting the friendliest individuals of the species. Dmitri Belyaev replicated domestication in a laboratory setting proving that human domestication can alter species in a relatively short time (not the millions of years that Darwin envisioned). Humans altered evolution through domestication. At the same time, domestication altered human civilization because it led to agriculture and trade. Then in the 18th century the English agriculturist Robert Bakewell invented modern (quasi-scientific) sheep and cattle breeding. His success in creating new kinds of cows and sheep inspired Darwin’s theory of evolution by natural selection (or, in this case, “artificial selection”). Now there are 800 different breeds of cattle and 300 breeds of dogs (and, again, the dog is simply a genetically-modified wolf). The hornless cow was originally a rarity, but through selective breeding it became the standard that cows don’t have horns. Pilcher mentions the rarely discussed beginning of genetic engineering: the “gamma ray gardens”, vegetable gardens in which vegetables were exposed to radioactive isotopes like cobalt-60 and caesium-137 (for example at the “atomic garden” established in 1949 at Brookhaven National Laboratories in Rhode Island). The phenomenon of “mutagenesis” had been known since at least 1926, when Hermann Muller demonstrated that exposure to x-rays caused genetic mutations in the genome of fruit flies and Lewis Stadler at the University of Missouri was studying corn mutations caused by X-rays and ultraviolet rays. They realized that radiation could speed up evolution. The “atomic garden” legitimized the irradiation of plants, in particular edible plants. “Atomic” plants and seeds became so popular that in 1959 a Muriel Howorth founded the Atomic Gardening Society in Britain. The genetic mutations were random (or, better, unpredictable) and often resulted in plants simply dying. But occasionally a plant would be created that looked more interesting than the natural variety. In 1960 a Clarence Speas founded Oak Ridge Atom Industries to sell cobalt60-improved seeds. Today we owe to those reckless “mutagenic” experiments an estimated 2,700 new varieties of plants, including most sweetcorn varieties. Most of today’s mint oil comes from a disease-resistance peppermint plant developed in 1971 at the Brookhaven National Laboratory. If you taste mint in your toothspace or chewing gum or ice cream, most likely it is “atomic” mint. Radiation breeding is responsible for many of the gorgeous orchid, tulip and rose varieties that make modern bouquets so colorful. Irradiating animals with radioactive isotopes so not as efficient, so it ook a safer method to genetically engineer animals. In 1974 Rudolf Jaenisch and Beatrice Mintz injected viral DNA into the DNA of early mouse embryos and produced the first transgenic mammals: the foreign DNA integrated into the mouse genome and was also passed on to the mouse’s offspring. Since then, scientists like Richard Palmiter have played with transferring genes from one animal species to another species. The first edible result of these gene-transfer technology was the AquAdvantage salmon, developed in 1989 by Memorial University in Newfoundland in Canada and commercialized by Boston’s AquaBounty Technologies, approved for consumption in Canada in 2016 and in the USA in 2019. The same gene-transfer technology has been used to create the fluorescent fish GloFish, originally developed in 1999 by Zhiyuan Gong’s team at the National University of Singapore for other reasons. Spider silk is an amazing material: it has five times the tensile strength of steel. In 2000 Nexia Biotechnologies, a spin-off of McGill University in Canada, announced the creation of goats “augmented” with spider genes so that they were able to produce milk equivalent to spider silk. The startup went bankrupt but Randy Lewis at Utah State University has continued its research. In 2015 Scott Fahrenkrug’s Recombinetics in Minnesota used the more sophisticated TALEN method to create two calves, Spotigy and Buri, whose offspring should never have horns again, thus potentially eliminating forever the cow with horns. And recently an even more advanced method called CRISPR has been used to genetically engineer new varieties of pigs, goats, rabbits as well as tomatoes and mushrooms. Dolly the Sheep, the first cloned animal (July 1996 in Britain), led to cloning of cattle in Wisconsin (just a few months later in 1997), to cloning cats (the Carbon Copy cat of 2001 in Texas), cloning of dogs (“Snuppy” in 2005 in South Korea) and cloning of horses (“Prometea” in 2003 in Italy), and even to dreams of de-extinction (bringing back species that are extinct like the mammoth). Pilcher then turns to the organisms that we kill, or, better, exterminate, which is another way to alter the environment and the course of evolution. The emblematic story is the story of the screwworm, that has been virtually annihilated in north America using the “sterile insect” technique pioneered by Edward Knipling in 1958: the worms were made sterile by exposing them to radiations and then released to mate in the wild. There are research programs on “gene drives” to exterminate the mosquitoes that spread malaria, following the 2014 experiments of CRISPR-engineered gene drive by Valentino Gantz and Ethan Bier on fruit flies at UC San Diego. In 2015 Gantz developed gene-drive mosquitoes in the lab, and at the same time Andrea Crisanti’s team achieved the same result at Imperial College London (both used CRISPR). In 2018 Kimberly Cooper at UC San Diego engineered the first gene drive in a mammal (in mice). There are more traditional ways to exterminate species: hunting them. Pilcher devotes a chapter to the systematic extinction of the “megafauna” by human hunters. Quote: “Humans are responsible for the biggest dying the world has seen since the demise of the dinosaurs”. At the same time domesticated animals proliferated, to the point that today the chicken is the most common bird (70% of all birds are chickens). The chicken is a recent “invention”: it originated from a fowl of the tropical forests of the Indian subcontinent and it was imported in Europe by the Phoenicians, and then European colonists spread it everywhere. Originally, chickens were small and mostly raised for eggs; but selective breeding made the chicken bigger and bigger, and today they are more valuable as food. Humans kill 65 billion chickens every year. Humans also deported domesticated animals from their natural habitats: most farm animals are born and raised in factory farms, not in their natural environment (or, better, the factory farm has become the natural environment of these selected animals). First we selectively bred domesticated animals and then we relocated them to concentration camps. The way humans change and pollute the environment has also an effect on the evolution of other species. Pilcher details the cases of swallows, moths and spiders that have “adapted” to the new environments created by humans. The speed with which humans transport species from one end to the other of the planet has also an effect on those ecosystems. Pilcher ends the book with notes on conservation projects as well as re-wilding projects like the Knepp Estate and the Oostvaardersplassen. The book presents a great overview of the ways humans have altered not only the environment but the evolution of life itself.