How could patriarchy/matriarchy develop in a species without sexual dimorphism?

Question

This hypothetical sapient species utterly lacks sexual dimorphism, such as due to being synchronous hermaphrodites (male and female at the same time), sequential hermaphrodites (change sex depending on circumstances) or isogamous (similar to hermaphrodites, but gametes are not segregated into ovum and sperm).

How could the species develop anything resembling our concepts of patriarchy, gender roles, homophobia, etc?

Answer 1

I'm not sure they could develop our concepts of gender roles etc, but they might have their own. For instance, if there is any genuine behavioural difference in a sequential hermaphrodite or synchronous hermaphrodite when pregnant, then that might get culturally exaggerated. So for example, imagine the pregnant ones have to pluck out their eider down to make a nest (like an eider duck) and peck out the eyes of the dead to get the fatty retina to make their egg yolk (like carrion birds). Their culture might decide any job which can be associated with nest building or the dead is 'pregnant women's work'. Those pregnant guys are just suckers for eyeballs - better send them off to work at the abattoir!

It can't work entirely like our prejudices and assumptions, because they are not female and/or pregnant all the time. It's difficult to treat Janet as a 2nd class citizen because she's a woman, when she might become a man next week, and you might become a woman the week after!

Homophobia could still arise if they creatures have cultural taboos against what type of genitalia are involved when your creatures bump uglies. If Janet and John get it on as male and female, they may have no problem. If John turns into a woman and leaps into bed with Janet again, it could be culturally prohibited.

It gets more complex when they are simultaneous hermaphrodites, but you could try Storm Constantine's Wraeththu Mythos books for inspiration. Although they are hermaphrodite, the Varr tribe adopts masculine and feminine roles (warrior, housekeeper). And the Natawni tribe has religious rules on what gender role they should take in sex at particular points in the calendar.

Meanwhile, even for hermaphrodites, fathering a kid is less effort than bearing offspring. Even when you are a snail and the offspring are eggs which don't require any care. There are species of slug for which the foreplay is trying to bite off each other's penis! Because if the person you are having sex with has no penis then:

1. You can get them pregnant, but they can't get you pregnant.
2. Instead of having to spend effort/resources on that clutch of eggs in your belly, you can head off to make more sperm and father more offspring.
3. The guy who has had his/her penis bitten off will not be competing with you to impregnate the next slug to come along.

(Note for the gentlemen reading this: don't worry, the penises do grow back).

So if they are like sea slugs, your hermaphrodites can create a class of people to be prejudiced at, by chopping off their penises!

Answer 2

I just recently read The Left Hand of Darkness, By Ursula K. Le Guin. I think that if it does not contains the answers you seek, at least it shall be a great source of inspiration.

The story happens in a world where the people are all hermaphrodites. They remain assexual for all purposes for 22-24 days, then go into oestrus for 2-4 days. During oestrus their bodies will develop either male or female secondary characteristics, depending on environmental circumstances and chance. For example, for those who go into oestrus alone they have equal chances of developing male or female characteristics, but if they go into oestrus around other people who are also in oestrus, their bodies will react to keep the numbers of male and female individuals approximately equal.

If they get pregnant, they will keep the female characteristics until a few months after childbirth.

Last but not least, they have no concept of marriage as we know it. They may vow fidelity, but it only means "I will always have intercourse with you whenever our ouestrus is in sync and you are around", not "I will be faithful until death do us part".

Due to this, any person can be a mother to a number of children from many fathers, and also a father to another amount of children from many mothers. They keep a loose track of who is father to whom, but mother-to-child bonds are nearly sacred. Thus clans are "matriarchal". But since everybody has both sexes, the term "matriarchy" is probably not the most appropriate one. The people from the book live in a society where the very concept of gender does not exist outside the physical part of sexual intercourse.

Therefore, every clan centers on a parent individual that has nursed their children.

There is a short story by the end of the book about a clan that takes pride on their children always having their first sexual relationships as females, and pride on not taking vows of fidelity. But this is the same kind of pride that a family from Earth could have about, say, having many engineers or doctors in the family, or making nice pies.

Seriously, go read that book. It's an awesome read. Praise the creation unfinished!