公元700年代末：斯堪的纳维亚半岛的农业发展滞后。生长季节短，土壤贫瘠，粮食作物几乎无法生产。大多数北欧人以捕鱼、狩猎、畜牧和劫掠为生。它们的食物：富含脂肪的鱼类（鲑鱼、鲱鱼）、海豹、鲸脂（如有）、牛羊奶制品，偶尔也吃猪肉。谷物是补充饲料。孩子们从小就以生牛奶和富含脂肪的鱼类为主食。农业时代的欧洲：农民以谷物粥为主食，偶尔吃些蔬菜，肉类摄入量极少。蛋白质摄入量受社会阶层限制。贵族吃肉，其他人则以谷物为主食。公元793年：维京人袭击林迪斯法恩岛。据记载，袭击者身材异常高大，力大无穷，令人恐惧。这种模式持续了250年。维京人的劫掠之所以成功，部分原因是战术，但也是因为他们体格更强壮。维京人平均身高：5英尺9英寸至5英尺11英寸。骨骼强健，牙齿良好，身体健康。骨骼分析显示缺陷极少，愈合能力强。欧洲农民平均身高：5英尺4英寸至5英尺6英寸。龋齿常见，营养不良，骨骼较弱。维京人并非基因超人。他们吃的是富含脂肪的鱼类和动物制品。而欧洲人主要吃谷物。当维京人在征服的领土——诺曼底、英格兰、爱尔兰——定居时，会发生一些事情：第一代：体格强壮，保持北欧人的体型。第二代：开始缩小。第三代：外貌与其他人无异。是什么改变了这一切？饮食。北欧定居者开始采用当地的农业饮食。谷物摄入量增加，鱼肉减少。三代人之后，体格优势消失了。诺曼底地区有相关记载。公元911年：罗洛率领的维京人定居于此。他们明显比法兰克人更高大、更强壮。到公元1000年，他们的后裔在体貌特征上已与他们征服的法国人几乎没有区别。相同的基因，不同的饮食，不同的结果。反过来也是如此。在冰岛定居的北欧人，凭借着捕鱼和狩猎的传统，几个世纪以来一直保持着强健的体魄。维京时代大约在 1066 年结束，不是因为欧洲人的战斗力增强了，而是因为维京人融入了欧洲人的农业饮食。那些曾横行欧洲250年的战士，最终因饮食习惯的改变而消失。三代人食用谷物后，他们的外貌就和他们曾经劫掠过的所有人一样了。教训是：来自贫瘠农田的食肉海盗征服了农业社会，不是因为环境恶劣，而是恰恰因为环境恶劣。Late 700s AD: Scandinavian farming is marginal. Short growing season, poor soil, grain barely viable. Most Norse survive on fishing, hunting, herding, raiding.Their diet: Fatty fish (salmon, herring), seal, whale blubber when available, dairy from cattle and goats, occasionally pork. Grain is supplemental.Children grow up drinking raw milk and eating fatty fish as dietary staples.Agricultural Europe: Peasants eat grain porridge, occasional vegetables, minimal meat. Protein restricted by social. Nobility eat meat; everyone else eats grain.793 AD: Vikings raid Lindisfarne. Accounts describe raiders as unusually tall, physically powerful, terrifying.Pattern repeats for 250 years. Viking raids succeed partly through tactics but also because raiders are physically superior.Average Viking: 5'9" to 5'11". Strong bones, excellent teeth, robust health. Skeletal analysis shows minimal deficiencies and rapid healing.Average European peasant: 5'4" to 5'6". Dental cavities common, nutritional deficiencies, weaker skeleton.Vikings aren't genetic superhumans. They're eating fatty fish and animal products. Europeans eat mostly grain.When Vikings settle conquered territories - Normandy, England, Ireland - something happens:First generation: Physically dominant, maintain Norse size. Second generation: Starting to shrink. Third generation: Look like everyone else.What changed? Diet. Norse settlers adopted local agricultural diets. More grain, less fish and meat. Within three generations, physical advantage disappeared.This is documented in Normandy. 911 AD: Rollo's Vikings settle. Notably taller and more robust than Franks. By 1000 AD, descendants are physically indistinguishable from the French they conquered.Same genetics. Different diet. Different results.The reverse happens too. Norse settlers in Iceland maintaining fishing and hunting maintain robustness for centuries.Viking Age ends around 1066 not because Europeans got better at fighting, but because Vikings assimilated into agricultural European diet.Warriors who terrorized Europe for 250 years disappeared through dietary assimilation. Three generations of grain and they looked like everyone they'd raided.The lesson: Meat-eating sea raiders from marginal farmland conquered agricultural societies not despite their harsh environment but because of it.
