Modern man evolved from more primitve humans who were already tool makers and fire builders. This significantly altered the development of those early humans (e.g. homo erectus).
From
wikipedia:
An important change in the behavior of humans was brought about by the control of fire and its accompanying light.[15] Activity was no longer restricted to the daylight hours. In addition, some mammals and biting insects avoid fire and smoke.[4] Fire also led to improved nutrition from cooked proteins.[13][16]
Richard Wrangham of Harvard University argues that cooking plant foods might trigger brain expansion by allowing complex carbohydrates in starchy foods to become more digestible and in effect allow humans to absorb more food energy.[17][18][19] Wrangham has also suggested that eating cooked food is more "natural" for the human digestive system, because he thinks that the human digestive system evolved to deal with cooked foods, and that cooking explains the increase in hominid brain sizes, smaller digestive tract, smaller teeth and jaws and decrease in sexual dimorphism that occurred roughly 1.8 million years ago. He also argues that raw meat and vegetables could not have provided the necessary energy to support the normal hunter–gatherer lifestyle.[20][21]
Other anthropologists oppose Wrangham,[22] stating that archeological evidence suggests that cooking fires began in earnest only 250,000 BP, when ancient hearths, earth ovens, burnt animal bones, and flint appear across Europe and the Middle East. Two million years ago, the only sign of fire is burnt earth with human remains, which most other anthropologists consider to be mere coincidence rather than evidence of intentional fire.[23] The mainstream view among anthropologists is that the increases in human brain-size occurred well before the advent of cooking, due to a shift away from the consumption of nuts and berries to the consumption of meat.[24][25]
Changes to diet[edit]Because of the indigestible components of plants such as raw cellulose and starch, some parts of the plant such as stems, mature leaves, enlarged roots, and tubers would not have been part of the hominid diet prior to the advent of fire.[26] Instead, the consumption of plants would be limited to parts that were made of simpler sugars and carbohydrates such as seeds, flowers, and fleshy fruits. The incorporation of toxins into the seeds and similar carbohydrate sources also affected the diet, as cyanogenic glycosides such as those found in linseed and cassava are made non-toxic through cooking.[26]
The teeth of H. erectus over time showed gradual shrinking, suggesting that later members of the species converted from eating crunchier foods such as crisp root vegetables to softer foods such as meat and various cooked foods.[27][28] The evidence of cooking of meat comes from burned and blackened animal bones found at various archaeological sites.[29]
Wrangham suggested that by cooking meat, it acted as a form of "pre-digestion", allowing less food energy intake to be spent on digesting the tougher proteins such as collagen and the tougher carbohydrates. The digestive tract shrank, allowing more energy to be given to the growing brain of H. erectus.[30] Suzana Herculano-Houzel calculated that if they ate only raw, unprocessed food, humans would need to eat for 9.3 hours per day in order to fuel their brains, which use about twice as much resting energy by percentage as other primates.[31] Other scientists disagree with Wrangham's assumption. Neurobiologist John Allman believes that cooking did not affect the brain development of H. erectus, but rather contributed to the development of the brain in Neanderthals and early modern humans. Paleoanthropologist C. Loring Brace agrees with Allman's theory that cooking did not affect H. erectus development, stating that he has only found evidence of earth-oven cookware from the past 200,000 years, which does not correlate with the earliest known use of fire from 800,000 years ago. Carel van Schaik believes that cooking did contribute to human evolution, but it was not the only factor that led to the increased brain power of modern hominids. Rather, as Leslie Aiello suggests, the changes came in groups; increased consumption of meat, the smaller digestive system, cooking, and upright walking all contributed to the growth of the brain.[30]
None of these points were made in Deutsch's book, but I thought it was relevant nonetheless. The environment doesn't provide us with a cooked meal, and yet our digestive system depends on it. Most of the food that we eat raw has been heavily modified by our own selective breeding for 10,000s of years, so in their original form most of the food that would have been available to us when we first appeared would not have given us the same nutritional value. We are entirely dependent upon our own inventions and interference with the biosphere.
Joe Biden … putting the Dem in dementia since (at least) 2020.
Not that I think it will care for us in any way, (that's ridiculous), but in the sense that it is travelling through space. 
