question: How did early humans figure out what plants and animals were safe to eat? Especially foods like the puffer fish which has to be prepared a specific way to avoid being poisoned
comment: The same reason why people are so taken aback by evolution and other incredibly long lasting process they can't imagine it. Early Humans / Monkies ate literally everything when they were hungry, things that made you survive were remembered as good, things that killed you or made you sick were avoided. Even Romans didn't outright build cities, but used already existing villages with proven water supplies and other resources. It wouldn't be so rare in ancient times to settle somewhere and that settlement dies and they see well theres something bad these don't go there. They don't know what but they saw people died for some reason. People just noticed things like boiling water seemed to remove the "bad stuff" some would call it humors other miasma today we call it micro organisms. Another way was feeling it to animals. People noticed dogs would die while eating large animal livers, they didn't know it was vitamin A toxicity but say the Inuit people don't eat Seal or Polar bear livers, technically they could eat like 50g and be okay. But since they observed people getting sick and dying together with dogs they simply avoided it altogether. Fugu as you might or might not know produces the most of it's toxin in the liver. Fugu isn't really prepared in any super special way you're just removing the internal organs specifically the liver. Even monkies don't eat intestines. They simply know it's bad and it tastes bad. And it gets passed on. Some things become tradition. URL_0
passages: Section::::History.
  
  Dioscorides, a Greek physician in the court of the Roman emperor Nero, made the first attempt to classify plants according to their toxic and therapeutic effect. Ibn Wahshiyya wrote the "Book on Poisons" in the 9th or 10th century. This was followed up in 1360 by Khagendra Mani Darpana.
  
  Mathieu Orfila is considered the modern father of toxicology, having given the subject its first formal treatment in 1813 in his "Traité des poisons", also called "Toxicologie générale".
   Pliny the Elder describes over 7000 different poisons. One he describes as "The blood of a duck found in a certain district of Pontus, which was supposed to live on poisonous food, and the blood of this duck was afterwards used in the preparation of the Mithridatum, because it fed on poisonous plants and suffered no harm."
  
  Section::::Origins of poison.:India.
  
  Indian surgeon Sushruta defined the stages of slow poisoning and the remedies of slow poisoning. He also mentions antidotes and the use of traditional substances to counter the effects of poisoning.
   While basic research in toxicology began in multiple countries in the 1800s, it was not until around the 1930s that the use of acute toxicity testing, especially on fish, was established. Over the next two decades, the effects of chemicals and wastes on non-human species became more of a public issue and the era of the "pickle-jar bioassays" began as efforts increased to standardize toxicity testing techniques. 
   Poisoned weapons were used in ancient India, and war tactics in ancient India have references to poison. A verse in Sanskrit reads ""Jalam visravayet sarmavamavisravyam ca dusayet"," which translates to "Waters of wells were to be mixed with poison and thus polluted."
   In 1850, Jean Stas became the first person to successfully isolate plant poisons from human tissue. This allowed him to identify the use of nicotine as a poison in the Bocarmé murder case, providing the evidence needed to convict the Belgian Count Hippolyte Visart de Bocarmé of killing his brother-in-law.
   Unlike many civilizations, records of Egyptian knowledge and use of poisons can only be dated back to approximately 300 BC. However, it is believed that the earliest known Egyptian pharaoh, Menes, studied the properties of poisonous plants and venoms, according to early records.
  
  The Egyptians are also thought to have come into knowledge about elements such as antimony, copper, crude arsenic, lead, opium, and mandrake (among others) which are mentioned in papyri. Egyptians are now thought to be the first to master distillation, and to manipulate the poison that can be retrieved from apricot kernels.
   In liaison with his commitment in public health matters and institutions, he involved himself in various studies on toxics, human nutrition and health, and the safety of industrial processes: thus he successively investigated toxins in toadstools ("Recherches chimiques sur les champignons vénéneux", 1856), medicinal real or supposed properties of diverse plants, herbs and preparations, toxicity of lead in widespread tins used for cooking utensils, poisonous effects of rye.
   Some crew members of the circumnavigation expedition led by Matthew Flinders made a similar error, consuming the toxins of "M. riedlei" while anchored at the south coast. At the founding of the Swan River Colony in 1829 Captain Fremantle was the first to taste three of the 'ground nuts' found at a local camp-fire, describing the taste as inoffensive and similar to 'roast potato'. He awoke the next morning with the symptoms of poisoning and recovered later that day after taking tea as an emetic and a period of sleep. Charles Fremantle testily records that despite witnessing and being informed of the consequences of eating the same, many of the men and two officers did just that and some suffered severe reactions.
   In 1580, a miner named Adreas Berthold traveled around Germany selling Silesian terra sigillata made from a special clay dug from the hills outside the town of Striga, now Strzegom, Poland, and processed into small tablets. He promoted it as a panacea effective against every type of poison and several diseases, including plague. Berthold invited authorities to test it themselves. In two cases, physicians, princes and town leaders conducted trials involving dogs who were either given poison followed by the antidote or poison alone; the dogs who got the antidote lived and the dogs who got the poison alone died. In 1581, a prince tested the antidote on a condemned criminal, who survived.
   Halotus worked as a servant for Claudius and also held the position of official taster, an occupation which entailed his tasting of a portion of every meal Claudius ate each day for poison. Tasters also worked to detect less sinister problems with the Emperor's meal, such as whether the food was fit to be consumed.
   Maitland also experimented on the diet of the trout and salmon at the fishery; he worked out that horse spleen when ingested by trout caused blindness and nutritional cataracts. He worked on several options before concluding that the best option for feeding trout and salmon was horsemeat, shellfish and eggs.
   Food poisoning has been recognized as a disease since as early as Hippocrates. The sale of rancid, contaminated, or adulterated food was commonplace until the introduction of hygiene, refrigeration, and vermin controls in the 19th century. Discovery of techniques for killing bacteria using heat, and other microbiological studies by scientists such as Louis Pasteur, contributed to the modern sanitation standards that are ubiquitous in developed nations today. This was further underpinned by the work of Justus von Liebig, which led to the development of modern food storage and food preservation methods. In more recent years, a greater understanding of the causes of food-borne illnesses has led to the development of more systematic approaches such as the Hazard Analysis and Critical Control Points (HACCP), which can identify and eliminate many risks.
   Theophrastus Phillipus Auroleus Bombastus von Hohenheim (1493–1541) (also referred to as Paracelsus, from his belief that his studies were above or beyond the work of Celsus – a Roman physician from the first century) is also considered "the father" of toxicology. He is credited with the classic toxicology maxim, ""Alle Dinge sind Gift und nichts ist ohne Gift; allein die Dosis macht, dass ein Ding kein Gift ist."" which translates as, "All things are poisonous and nothing is without poison; only the dose makes a thing not poisonous." This is often condensed to: "The dose makes the poison" or in Latin "Sola dosis facit venenum".
   Many of the early bioassays consisted of using animals to test carcinogenicity of chemicals. One well known example is a "canary in the coal mine" experiment. To test for methane, miners would take methane-sensitive canaries to coal mines to ensure safe air. In 1915, Yamaigiwa Katsusaburo and Koichi Ichikawa tested the carcinogenicity of coal tar using inner surface of rabbit's ears.
  
  Through 1940s and 1960s, animal bioassay was primarily used to test for toxicity and safety of drugs, food additives and pesticides.
   The next advancement in the detection of poisons came in 1850 when a valid method for detecting vegetable alkaloids in human tissue was created by chemist Jean Stas. Stas's method was quickly adopted and used successfully in court to convict Count Hippolyte Visart de Bocarmé of murdering his brother-in-law by nicotine poisoning. Stas was able to successfully isolate the alkaloid from the organs of the victim. Stas's protocol was subsequently altered to incorporate tests for caffeine, quinine, morphine, strychnine, atropine, and opium.
   Poisoned arrows are also still used in the jungle areas of Assam, Burma and Malaysia. The ingredients for the creation of these poisons are mainly extracted from plants of the "Antiaris", "Strychnos" and "Strophanthus" genera, and "Antiaris toxicaria" (a tree of the mulberry and breadfruit family), for example, is used in the Java island of Indonesia, as well as several of its surrounding islands.
   Several species of "Aconitum" have been used as arrow poisons. The Minaro in Ladakh use "A. napellus" on their arrows to hunt ibex, while the Ainu in Japan used a species of "Aconitum" to hunt bear. The Chinese also used "Aconitum" poisons both for hunting and for warfare. "Aconitum" poisons were used by the Aleuts of Alaska's Aleutian Islands for hunting whales. Usually, one man in a kayak armed with a poison-tipped lance would hunt the whale, paralyzing
  
  it with the poison and causing it to drown.
  
  Section::::Cultivation.
   According to Homer's epic poems about the legendary Trojan War, the "Iliad" and the "Odyssey," spears and arrows were tipped with poison. During the First Sacred War in Greece, in about 590 BC, Athens and the Amphictionic League poisoned the water supply of the besieged town of Kirrha (near Delphi) with the toxic plant hellebore. During the 4th century BC Scythian archers tipped their arrow tips with snake venom, human blood, and animal feces to cause wounds to become infected.
   Section::::Later imperial Asia.
   Tribal people historically used various plants for medicinal and food exploitation purposes. Use of fish poisons is a very old practice in the history of humankind. In 1212 AD, King Frederick II prohibited the use of certain plant piscicides, and by the 15th century, similar laws had been decreed in other European countries, as well. All over the globe, indigenous people use various fish poisons to kill fish, including America and among Tarahumara Indians.
   Chemical testing of the waters was described in "Spadacrene Anglica", and Stanhope's later work, based in particular on the "gall test" going back to Conrad Gesner. These are early mentions of this chemical indicator in the English literature: Gesner's ideas had been translated by Thomas Hill in his "Newe Jewell" of 1576, but little intervening interest was shown. The tradition of chemical analysis was continued by French and Robert Witty (1660), and was praised by Samuel Hartlib.
   Section::::Accidental poisoning.
  
  On the occasion in question, Neal sent James Archer, a lodger who lived at his house, to collect daff for Hardaker's humbugs from druggist Charles Hodgson. Hodgson's pharmacy was away at Baildon Bridge in Shipley. Hodgson was at his pharmacy, but did not serve Archer owing to illness and so his requests were seen to by his young assistant, William Goddard. Goddard asked Hodgson where the daff was, and was told that it was in a cask in a corner of the attic. However, rather than daff, Goddard sold Archer of arsenic trioxide.
   BULLET::::- Roman Empire – There is speculation that the Romans, in particular the elite, suffered chronic to severe lead poisoning due to the ubiquity of lead in e.g. lined pots in which acidic foodstuffs were boiled, over and above any mere exposure to lead in water pipes. They also used sugar of lead to sweeten their wines.
  
  Section::::List of notable incidents.:Middle Ages.
  
  BULLET::::- Europe - numerous incidents of human poisoning due to the consumption of rye bread made from grain infected with ergot fungi
  
  Section::::List of notable incidents.:19th century.
  
  BULLET::::- 1850s – Swill milk scandal in New York
   The German physician Engelbert Kaempfer, in his "A History of Japan" (translated and published in English in 1727), described how well known the toxic effects of the fish were, to the extent that it would be used for suicide and that the Emperor specifically decreed that soldiers were not permitted to eat it. There is also evidence from other sources that knowledge of such toxicity was widespread throughout southeast Asia and India.
   Section::::Basic principles.
  
  The goal of toxicity assessment is to identify adverse effects of a substance. Adverse effects depend on two main factors: i) routes of exposure (oral, inhalation, or dermal) and ii) dose (duration and concentration of exposure). To explore dose, substances are tested in both acute and chronic models. Generally, different sets of experiments are conducted to determine whether a substance causes cancer and to examine other forms of toxicity.
  
  Factors that influence chemical toxicity:
  
  BULLET::::- Dosage
  
  BULLET::::- Both large single exposures (acute) and continuous small exposures (chronic) are studied.
  
  BULLET::::- Route of exposure
  