You are human in an agricultural community.

You are a baby

You, a baby, cry because you feel like it.

There used to exist babies in the agrarian community — from the previous generation — who did not cry. 

These babies died 
    when their needs weren't met 
    because people forgot about these babies existing.

The parents in the community have an urge to address crying babies because "communities with parents who didn't address crying babies" died out when
     1. The babies died.
     2. The humans ("parents") could no longer reproduce.
     2a. The humans died without reproducing.

Your father's estate addresses your needs as you grow up.

Suppose you are a woman

You are now a woman of child-bearing age who is ovulating.

You do not decide to

have an increased urge to have sex [1].
find all men hotter, and exponentially for your sexual "type" [2].
direct more visual attention towards men you find attractive [3].
experience increased self-esteem and self-perceived sexual desirability [4], energy, and a more creative personality [5].
experience physical changes such as peaked facial skin redness (blushing) [6].

However, these subconscious actions occur without your awareness.

You can speculate these traits (of the menstrual cycle) exist because humans with these traits reproduced more than "humans" lacking these traits.

Suppose a man approaches you and engages in sexual intercourse with you.

There is a high chance you know this man from your marriage, which is an economic contract [7, 8]. The community incentivizes and enforces laws upon this contract by tying your survival to its terms: You cannot work or own your own property as a woman.

Your family and village elders constrained or directed your selection of this man to secure family alliances, resource stability, and property rights instead of your sexual preferences[7].

Your family and village elders heavily negotiated or approved this match, which aligned the marriage with the village's economic survival

You might moan during sex because

You feel like it.
This behavioral trait is inherited from a prior generation of humans' which implies that there is a reason to moan or a lack thereof (which effects reproduction potential) [10].
This behavioral trait might be inherited from an environment where the behavior was evolutionary advantageous, but now the vestigial behavior has no evolutionary advantage or disadvantage [9].

The man orgasms before you do. Then, he exits your body.

Suppose you have not been satisfied and continue to have sex.

You address this lack of satisfaction with the man, who might provide you with post-coital intimacy before he rests.

There is a smaller chance you were not married to this man prior to sexual intercourse.

You keep any sexual encounter with a man who is not your husband secret [11, 12] to protect your physical resources (provided by your husband or family who is finding you a husband) and your social stability [7, 8].

You have sex with this man despite the lack of marriage with him because you felt sexually attracted to him [11, 12].

The man orgasms before you do. Then, he exits your body.

Suppose you have not been satisfied yet.

You might continue to have sex with this man by waiting for his refractory period to clear.
You might feel sudden frustration, mood swings, or localized disappointment if he leaves before you want him to.
You might end the interaction upon his exit. You clean yourself and exit the situation.

Suppose you have a husband who is not this man.

You might initiate sexual contact with your husband later.
- This subconscious action creates paternity confusion for your husband, who maintains a high perception of paternity certainty based on his own physical interaction with you [9]. However, there is a small chance (estimated to be 1% to 2%) the child is not his [13, 14].
You might not initiate sexual contact with your husband, risking his suspicion and the enforcement of strict legal or spiritual laws against you [8].

You are not aware

Sperm can live up to 5 days inside your cervix, uterus, and fallopian tubes awaiting ovulation [15, 16].
The first sperm to your egg is not the winner [17].
Your egg has influence or choice over which sperm is accepted [17, 18].

You know who your child's biological father is only if you had sex with one man.

You ensure your husband feels like the child's biological father to secure your place in his household [7].

The community addresses your needs

as you are pregnant.
as you birth the child.
as you raise the child within your husband's estate.

You address the needs of

yourself.
then, your certain children (from your marriage).
then, your husband (the provider).
then, your community.

Suppose you are a man

You are a mature man who has a sexual urge.

You do not decide to

increase flow of blood to your penis.
increase the size of your testicles.
increase your heart rate, blood pressure, and breathing rate.
lubricate your urethra with fluid (colloquially called "pre-cum").

However, these subconscious actions occur without your awareness.

You can speculate these traits exist because humans with these traits reproduced more than "humans" lacking these traits.

Suppose you approach a woman and engage in sexual intercourse with her.

You might penetrate her in a thrusting motion because
    1) You feel like it.
    2) This behavioral trait is inherited from a prior generation of humans' which implies that there is a reason to thrust or a lack thereof (which effects reproduction potential).
	    a) a theory exists which asserts "a man's penis shape is designed to pull out other men's sperm and assist in sperm competition." \[19\]
        b) a more-recent  theory contradicts (a) by asserting "a man's penis shape is designed to perform a protective parting squeeze which secures the semen in the woman upon the man's withdrawal." \[20\]

You orgasm and enter the male refractory period.

Your penis reduces blood flow (colloquially called "becoming soft").
Your penis reduces blood flow and becomes hypersensitive to touch, while post-orgasm hormones eliminate your sexual urge. So, you exit her body.

You are not aware how many other men have had sex with the woman, but you are certain she hasn't had sex with anyone else because she is your wife. [9, 10]

Your wife cannot own property or work and is dependent on your provision [7, 8]. So, she is incentivized to follow the terms of her marriage, which is an economic contract [7, 8]. The contract is recognized by society and enforced by legal and spiritual law.

You can have multiple wives depending on the laws of your community but she must only have one husband [12].

So, you are certain you have children with your wives.

You address the needs of

yourself.
then, your certain children (conceived in marriage).
then, their caretakers (your wife).
then, your community.

Sources Used

[1] Arslan, R. C., Schilling, K. M., Gerlach, T. M., & Penke, L. (2018). Using 26,000 diary entries to show ovulatory changes in sexual desire and behavior. Journal of Personality and Social Psychology. https://www.mpib-berlin.mpg.de/press-releases/partner-choice-of-women

[2] Stern, J., Gerlach, T. M., & Penke, L. (2020). "Probing Ovulatory-Cycle Shifts in Women's Preferences for Men's Behaviors". Psychological Science. 31 (4): 424–436. doi:10.1177/0956797619882022. PMID 32130075. https://journals.sagepub.com/doi/10.1177/0956797619882022

[3] Anderson, U. S., Perea, E. F., Becker, D. V., Ackerman, J. M., Shapiro, J. R., Neuberg, S. L., & Kenrick, D. T. (2011). I only have eyes for you: Ovulation redirects attention (but not memory) to attractive men. Journal of Experimental Social Psychology. https://pmc.ncbi.nlm.nih.gov/articles/PMC3161129/

[4] Arslan, R. C., et al. (2023). Women feel more attractive before ovulation: Evidence from a large-scale online diary study. Evolutionary Human Sciences. https://pmc.ncbi.nlm.nih.gov/articles/PMC10427307/

[5] Galasinska, K., & Szymkow, A. (2022). Enhanced Originality of Ideas in Women During Ovulation. Frontiers in Psychology. https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2022.859108/full

[6] Burriss, R. P., et al. (2015). Changes in women's facial skin color over the ovulatory cycle are not detectable by the human visual system. PLOS ONE / University of Cambridge. https://www.cam.ac.uk/research/news/womens-faces-get-redder-at-ovulation-but-human-eyes-cant-pick-up-on-it

[7] Bowles, S. (2011). Cultivation, coevolution, and the emergence of property rights. Proceedings of the National Academy of Sciences. https://pnas.org

[8] Pasternak, B., et al. (1997). Sex, Gender, and Kinship: A Cross-Cultural Perspective.

[9] Schacht, R., & Kramer, K. L. (2019). Are We Monogamous? A Review of the Evolution of Pair-Bonding in Humans and Its Contemporary Variation Cross-Culturally. Frontiers in Ecology and Evolution, 7, 230. https://frontiersin.org

[10] Brewer, G., & Hendrie, C. A. (2011). Evidence to Suggest that Copulatory Vocalizations in Women Are Not Reflexive Responses to Orgasm. Archives of Sexual Behavior, 40(3), 559–564. https://springer.com

[11] Gangestad, S. W., & Simpson, J. A. (2000). The evolution of human mating: Trade-offs and strategic pluralism. Behavioral and Brain Sciences, 23(4), 573–587. https://cambridge.org

[12] Gangestad, S. W., & Thornhill, R. (1997). The evolutionary psychology of extrapair copulations: The role of symmetry and physical attractiveness. Evolution and Human Behavior, 18(3), 169–188. https://ehbonline.org

[13] Larmuseau, M. H. D., Matthijs, K., & Wenseleers, T. (2016). Cuckolded Fathers Rare in Human Populations. Trends in Ecology & Evolution, 31(5), 327–329. https://cell.com

[14] Larmuseau, M. H. D., van den Berg, P., Claerhout, S., et al. (2019). A Historical-Genetic Reconstruction of Human Extra-Pair Paternity. Current Biology, 29(23), 4102–4107. https://cell.com

[15] Mayo Clinic. (2026). Sperm: How long do they live after ejaculation? Mayo Clinic Expert Answers. https://mayoclinic.org

[16] Indira IVF. (2026). How Many Days Does a Sperm Live in a Female's Body? Conception & Timing Guide. https://indiraivf.com

[17] Fitzpatrick, J. L., et al. (2020). Chemical signals from eggs facilitate cryptic female choice in humans. Proceedings of the Royal Society B: Biological Sciences, 287(1928), 20200805. https://royalsocietypublishing.org

[18] Wedekind, C., et al. (1995). MHC-dependent mate preferences in humans. Proceedings of the Royal Society B: Biological Sciences, 260(1359), 245–249. https://royalsocietypublishing.org

[19] Goetz, A. T., & Shackelford, T. K. (2006). Sexual coercion, ejaculate characteristics, and semen displacement tactics. Semen displacement as a sperm competition strategy. Evolution and Human Behavior, 27(2), 123–134. https://sciencedirect.com

[20] Klug, M., et al. (2023). Morphological and physiological assessments of the human glans penis and alternative evolutionary hypotheses. An Evolutionary Advantage of the Human Glans Penis. Journal of Evolutionary Biology, 36(9), 1311-1324. https://oup.com