Finding Nemo’s sexual identity
- Shivan Parusnath
As a species, we are only starting to scratch the surface of our understanding of gender, sex, and identity.
Reversing stereotypical gender roles
The term “fathering instinct” does not have quite the same ring as “mothering instinct” because of our antiquated notion of women as primary caregivers. In contemporary human society, these stereotypical gender roles are falling away. After the birth of a child (and perhaps with the exception of breastfeeding) there is no reason that a father cannot be the primary carer.
The African Jacana – a bird well known for its large feet that allow it to walk on lily pads and live a waterborne life, epitomises a successful gender role-reversal. “Female African Jacanas are 60% larger than males and have a harem of up to five different males that they mate with each season,” explains Wits ornithologist Dr Chevonne Reynolds from the School of Animal, Plant and Environmental Sciences (APES).
“The males then go on to incubate the eggs and care for the chicks after hatching, while the female moves on to mate with the next male in her harem. The males of the species even have special adaptations to their wings that allow them to carry their chicks around with them.”
This strategy of the philandering female and the hard-working father teaches us that the labels and the roles that we assign to males and females may be just that – labels. Evolution simply favours what works.
The real reason why Nemo’s dad was so desperate to find him
While humans, the self-proclaimed highest form of intelligence on planet Earth, struggle to accept the notion of gender fluidity, many animals such as frogs and fish have been successfully doing so for ages, and without any notable transphobia to boot.
Clownfish, the popular aquarium fish, and star of the Pixar Studios movie “Finding Nemo”, engage when required, in a process called sequential hermaphroditism. The social structure of a group of Clownfish consists of a large dominant female and a smaller, dominant male. The remainder of the group is made up of small, sexually immature males (in fact, all clownfish are born male). If the dominant female dies, the dominant male will change sex and take her place at the top of the pack.
This “sex change” is a result of hormonal changes that cause the testes to dissolve and ovaries to form. The new female leader of the group will then seek out another male to become her partner. This unique sexual system may have evolved because of the close relationship that clownfish have with sea anemones – they tend to not venture far from home, and so a male becoming a female may be a safer strategy than roaming for a new mate. This may have been Nemo’s dad’s real inspiration to find his son – so “he” could become a “she” and mate with Nemo.
Finding a sexual partner can be challenging. At least, we, as humans have dating apps to help us when times get tough. But what do animals do if they don’t come across a sexual partner within their lifetime?
Since passing on genes to the next generation is perhaps the central driving force of most lifeforms – many species have evolved a creative way to ensure that their seed is spread. Females of certain species of insects, reptiles and fish amongst other animals are capable of reproducing parthenogenically – essentially fertilising their own eggs in order to create offspring.
“Unlike mammals, whose embryos start off as female (the default sex), the embryos of some reptiles and birds start off as males by default,” explains Wits herpetologist Professor Graham Alexander from the School of APES. “In the case of Komodo Dragons, there have been females in zoos that have never met a male of their species but have laid eggs that resulted in normal healthy babies.”
Interestingly, the babies are not exactly clones since their genetic make-up is the results of some chromosomal remixing – instead of half from a mom and half from a dad as in typical sexual reproduction. And since the babies produced this way are male – it would allow a single female Komodo Dragon to reproduce with her offspring and populate an island all by herself.
Dominance is a key factor in the rights to mate in the animal kingdom. “Superior” males may be those that are larger, more colourful, or more prominently ornamented. But it does not always mean that they possess superior genes – the outward appearance may simply be due to environmental factors during development such as better access to food as a juvenile.
But if luck is not on the side of smaller males, there are alternative mating strategies. Subordinate males of many species take on the appearance of a female, allowing them to get closer to females while avoiding the usual conflict with the alpha male.
“These sneaky fuckers get in with the females and do their business without the dominant males even noticing,” explains Alexander. The term “sneaky fuckers” was actually the preferred scientific lexicon for this strategy for a period, believed to be coined by renowned British biologist Tim Clutton-Brock. Today though, they are referred to using the more politically correct term ‘sneaker males’.
“An example of this from the insect world are horned dung beetles, where the males with large horns guard the tunnel of a female beetle with which they are reproducing,” says Wits entomologist Professor Marcus Byrne from the School of APES. “While no other males can get close to the female without getting into a fight, the less ornamented, ‘sneaker males’ dig a side tunnel to the female, where they do not appear to pose a threat to the guarding male. They then surreptitiously mate with the female while the ‘superior’ male is guarding the front door.”
- Shivan Parusnath is Senior Communications Officer for Wits University.
- This article first appeared in Curiosity, a research magazine produced by Wits Communications and the Research Office.
- Read more in the 13th issue, themed: #Gender. We feature research across disciplines that relates to gender, feminism, masculinity, sex, sexual identity and sexual health.