Agriculture, or the ability to produce food by growing it instead of hunting
it or gathering
it, has probably been robbed by the invention of fire
of the title of most significant development in human history
The life of a human being before agriculture was marked by the highest levels of "leisure time" of any subsequent society, fewer pervasive psychological disorders, equality among small social groups (including equality between genders), freedom from institutional conflicts, absence of "leaders" and "followers," as well as "property" and "territory," and required less "work per calorie" than any other method of organizing human endeavor ever invented since.
Organization was not unknown in this environment, but food gathering consisted primarily of hunting animals and gathering edible plants. There was a linear relationship between the effort to obtain food and the amount of food obtained. Also, any member of the society was capable of fending for themselves in "the wild" - which was really more like a really, really big backyard.
Meanwhile, food surpluses in primitive cultures led to non-egalitarian social hierarchies, rulers, "workers", law, slaves, wealth and poverty, eventually money, organized trade, social specialization, which led to the development of skill-based trades, such as police, doctors, metalworkers, weavers, animal tenders, thinkers and writers, teachers, artists, and so forth - numerous kinds of non-food producing jobs were now possible, since large quantities of food could now be harvested, stored, distributed, and traded more efficiently for other goods; and let's not forget large scale organized warfare with newly specialized soldiers, fought over the newly developed concept of wealth... trade, meanwhile, catalyzed the development of language, and specifically written language, as well as mathematics, and the sciences.
The net effect of this development is impossible to inclusively catalog. Other pervasive effects of agriculture upon human society include a dramatic change in gender roles and intersex relationships, an increased average lifespan, the tendency of people to congregate and cohabitate in increasingly, often pathologically, large groups, now called cities, the gradual erosion of the large, extended family and/or community social model and the rise of the nuclear family and "individualism," as well as "modern religion" - which is characterized by a patriarchal hierarchy, institutional mysogyny, monotheism, asceticism, elaborate behavioral codes and "laws," unification of state/religion/territory, violent conflict with other religions/beliefs and other manifestations of xenophobia, as well as, almost universally, a creation myth involving progenitors which are cast out of an innocent state into a harsh, punishing world by a vengeful God.
The book of Genesis is particularly telling, as it relates:
3:13 And the LORD God said unto the woman, What is this that thou hast done? And the woman said, The serpent beguiled me, and I did eat.
And the LORD God said unto the serpent, Because thou hast done this, thou art cursed above all cattle, and above every beast of the field; upon thy belly shalt thou go, and dust shalt thou eat all the days of thy life:
And I will put enmity between thee and the woman, and between thy seed and her seed; it shall bruise thy head, and thou shalt bruise his heel.
Unto the woman he said, I will greatly multiply thy sorrow and thy conception; in sorrow thou shalt bring forth children; and thy desire shall be to thy husband, and he shall rule over thee.
And unto Adam he said, Because thou hast hearkened unto the voice of thy wife, and hast eaten of the tree, of which I commanded thee, saying, Thou shalt not eat of it: cursed is the ground for thy sake; in sorrow shalt thou eat of it all the days of thy life;
Thorns also and thistles shall it bring forth to thee; and thou shalt eat the herb of the field;
In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return.