Population Wars

CHAPTER EIGHT: COMPETITION IS UNTENABLE

149. Literary conventions of politeness at the time restricted Malthus from suggesting anything overtly sexual. He writes of moral restraint: “In modern Europe a much larger proportion of women pass a considerable part of their lives in the exercise of this virtue, than in past times and among uncivilized nations … implies principally a delay of the marriage union from prudential considerations … it may be considered in this light as the most powerful checks, which in modern Europe keep down the population to the level of subsistence.” Malthus, Thomas R. (1817), An Essay on the Principle of Population; or, a View of its Past and Present Effects on Human Happiness; with an Inquiry into Our Prospects Respecting the Future Removal or Mitigation of the Evils which it Occasions, fifth ed., John Murray, London, vol. 2, p. 218.

153. Alfred Russel Wallace is considered the codiscoverer of natural selection. An observant naturalist who, like Darwin, traveled the world and spent years investigating the tropical rain forests, Wallace sent a letter to Darwin before the publication of Origin of Species. His letter outlined a view of natural selection that nearly matched the view Darwin came up with independently. Wallace, too, was inspired by what he read in Malthus’s Essay on Population. Darwin accepted Wallace’s ideas and agreed to present a paper jointly announcing their codiscovery of natural selection. After this Darwin stepped up his efforts to publish the more extensive treatment of the subject in Origin of Species. Hence the mechanism of evolution we recognize today is a blend of both their views. For evolution to occur, organisms must meet the basic requirements of their environment as well as outcompete other individuals for access to reproductive partners.

158. Neo-Darwinism is distinguished from Darwinism and neo-Lamarckism. Darwin recognized that organisms often possessed trivial or apparently nonuseful traits that were faithfully passed from parent to offspring, and that such traits could not be explained by natural selection. This recognition became one of the most important hallmarks of Darwinism: Natural selection explained adaptation, but not all traits were adaptations. After he died, neo-Darwinism, or “ultra-selectionism” as Vernon Kellogg called it (see Kellogg, Darwinism To-Day, pp. 38–39), became more popular. The origin of this distinction between neo-Darwinism and Darwinism comes from August Weismann, who by proving the separation of germ cells and somatic cells established the grounds for a “new” Darwinian worldview. Neo-Darwinism finally freed Darwinism from the “taint of Lamarckism.” Lamarckism is also called the “inheritance of acquired characteristics,” the idea that life experiences of the parents could be incorporated into the hereditary material. Weismann’s view was that natural selection is the only mechanism driving evolution forward. This extreme view was never advocated by Darwin. Nor was the notion of absolute separation of the somatic and germ cells. Darwin believed in hereditary molecules (gemmules) that were strongly influenced by the somatic cells. This made Darwin’s theory of heredity inherently Lamarckian. See reference in note 158, pp. 136 and 188, for further discussion.

CHAPTER NINE: KNOW THYSELF, DON’T LIE TO THYSELF

CHAPTER TEN: EVOLUTION MANAGEMENT

196. A recent study shows that some rugosans in the Silurian (443–418 mya), were tiny and endosymbiotically embedded into the skeletal tissue of stromatoporoids. Stromatoporoid reefs show extensive evidence of endosymbiosis with other species as well, such as Cornulites sp., an encrusting and burrowing wormlike animal. Other reef dwellers from this period show further evidence of endosymbiosis that does not involve stromatoporoids, Lingulid brachiopods (superficially resembling clams, but much different in their soft anatomy, with a muscular “foot” used for burrowing) inside of tabulate corals, for instance. Hence reef organisms have a long history of endosymbiosis that continues to this day, even though the species that form them through time have been different. See Vinn, O., and M. A. Motus (2014), Endobiotic Rugosan Symbionts in Stromatoporoids from the Sheinwoodian (Silurian) of Baltica, PLoS One, 25, 9, no. 2.