The Puzzle of Our Parenting

             

With every passing decade human beings seem more and more like aliens who arrived on Earth by some incredible (and perhaps terrible) accident. We don’t fit in harmoniously with other living creatures. We pursue the creation of our own isolated “human” societies that distinguish us from common flora and fauna. What’s more, many of us seem quite content with this solitary existence.

Our lonely human cocoons are comforting because they allow us to pretend that we are above the laws of nature. We rarely speak about ourselves with the same impersonal biological theories that we use for other species. And there are some human experiences that we hold so dear - that to apply scientific principles to them is akin to blasphemy. 

The Altar of Parenting

The idea that human beings are the most committed, diligent, and selfless parents of all living beings is widely accepted. Accepted is actually a rather small word - the altar of parenting is worshipped. Human parents are celebrated in everything from international holidays to devout religious texts. Even scientists dislike interrupting this celebration to discuss human parenting as a behavior subject to evolutionary biology. It’s preposterous to say that human parents have the same evolutionary drive to pass on their genes and ensure the survival of their children as grasshoppers, bluebirds, or dolphins do. No - humans parents are the pure embodiment of unconditional love.

Of course, millions and millions of human parents love their children immensely. But principles of evolution can still be applied to analyze our parenting behavior. These two perspectives are not mutually exclusive. In fact, what kind of parents would we be if we didn’t use science to better understand ourselves?

And so, I write this paper to assert that we are not the only dedicated parents in this world, that the same evolutionary principles that we apply to other animals apply to us too, and that we may learn to be better parents by looking at the fascinating animal parents we share this planet with.

The Mathematics Behind Parenting

The driving force of evolution is the degree to which various physical traits, cognitive processes, or social behaviors accomplish the task of passing on an organism’s genes. In the context of evolution, we are a mere vessel for our genetic code. The goal of parenting is inextricably linked to the continuation of this code in our children. If sex is the human behavior that evolved from the drive to conceive children, parenting is the human behavior that evolved from the drive to keep those children alive. 

Your biological child will have half of their genes in common with you. If you have one child, half of your genes will be carried on. If you have ten children, your entire genetic code could be copied up to five times (10 X 0.5 = 5). So, as the number of children you have goes up, your evolutionary success increases as well. But it doesn’t stop with children - if you raise children and they survive to have children of their own - your grandchildren will have a quarter of your genetic material. If you are an exceptionally good parent, you will raise successful children, who will successfully raise grandchildren - each successive generation ensures your evolutionary legacy. 

For those animals who cannot reproduce, or chose not to, their genetic lineage is not necessarily over. A niece, nephew, or young cousin can all be worth the investment of parental care - if there are enough of them. If you forgo having two children (each one 50% identical to you) to raise four nieces and nephews (each one 25% identical to you) - you have achieved approximately the same genetic success - although, at a higher cost. 

But of course these calculations help us understand how parenting is perpetuated through multiple generations and species - not how it originated. The first animal parent did not calculate the benefit of parenting before doing it.

The Origins of Parenting

Parenting arose when individuals in a species had mutations that increased the likelihood of their children surviving. These first few mutations did not lead to parenting behaviors as complicated as building a nest or teaching young how to forage for food. But even simple behaviors such as sitting on an egg or giving birth around a food source can dramatically increase the likelihood of offspring survival. And if they survive to reproduce - these mutations will be carried on. With each successive generation, the children of the best parents were better at surviving and having kids than children of inept parents. Parenting behavior is so genetically powerful that it becomes nearly universal in every species where it evolves. Today, some form of parental care is present in nearly every animal on earth.

So why don’t we all parent the same way?

Simply put, parenting in various species is so different because animals themselves are so incredibly different. Every parent on Earth has evolved (and is still evolving) to spread as many “copies” of their genes as possible. But some animals live for a century and others live for a month. Some are male, others are female. Some are social animals, while others live solitary lives. The result of this myriad of differences is that every parent invests a different amount of time and effort. And this investment can be divided up in a variety of ways - both across tasks and across children. Parenting is an evolutionary strategy. It is tailored to the specific game of chess between each species and the extinction of their genes.

I want to share with you my investigation of two particularly unique animal parents. There were three goals of each investigation: uncover the evolutionary logic behind an animal’s parenting behavior, utilize this to explain larger themes in parenting across species, and apply this understanding to human parents in order to discover evolutionary holes in our parenting philosophies.

Family Feast

The Stegodyphus Spider

To any arachnophobe reading this: good luck. 

Somewhere in the Israeli desert there lives a female of the Stegodyphus genus who is meticulously crafting her silk web in the dead of night. It needs to be absolutely perfect. She will soon be the mother of dozens of baby spiders. And if she is successful, this will be her first and last time experiencing the joy of motherhood. And this joy is rather short-lived. When the eggs hatch, a restful “postpartum” period is non-existent. The first task of motherhood awaits: digesting herself. The enzymes that ravenously disintegrated insect prey in preparation for the birth of the spiderlings will now turn their attention to the mother’s own bodily tissues (Alchetron 2018). As her own nutrients collect in her gut, the mother regurgitates this liquid out for her young. This will be their food for the first two weeks of their lives. At the end of these two weeks comes the grand finale - the only meal left for the young spiderlings is whatever remains of their mother. And so the final moments of a Stegodyphus mother are spent being eaten by her children till all that is left is a ghostly exoskeleton.

You would think (or perhaps hope) that this parenting story couldn’t get darker - but the males of the species ensure that the tragedy doesn’t end here. Adult males lunge at every possible opportunity they have to destroy any eggs that aren’t their children. As expectant mothers are saving up bodily nutrients for their impending doom, males are fighting for ways to detach an egg sac from a mother’s web and toss it to the ground. In fact, one third of unhatched eggs can be attributed to adult males comitting infanticide (Schneider 1997, 305).

How can mothers and fathers of the same species behave so differently? Researchers explored this question by documenting the specific evolutionary costs and benefits for both parents.

Maternal Costs and Benefits

With everything that mothers do for this species, it may only be fair to start with them. It’s needless to say that maternal cost is enormous for this genus. Successful motherhood requires no less than suicide. But even unsuccessful motherhood comes with it's costs. If eggs fail (due to male infanticide, disease etc.), the female will have lost all of the time since the eggs were laid plus all the time it takes to lay new ones. Spiders already have short life spans. There is an average delay of 18.5 days between eggs being lost and new eggs being laid - during which the female’s chance of survival goes down by nearly 25 percent. If the female survives to lay a replacement clutch, chances are that it won’t match her previous clutch in either quantity nor quality. The longer the delay between the clutches, the fewer eggs are laid. And the eggs that are laid are likely to be significantly smaller in size - indicating that much less nutrition is available for the spiderlings. In short, a female’s second clutch is not an evolutionary victory. It is a mother’s last-ditch attempt to have a genetic legacy. Spider mothers would much rather try their absolute hardest to defend their first (and hopefully only) clutch. The mother can do little to protect against disease in her eggs, but there is an option to guard against male infanticide. Unfortunately - like seemingly everything spider females do - there is a cost to this. Fighting male spiders who’ve trespassed her web may cause devastating injury. Particularly gruesome fights result in death. With everything we’ve learned so far, the life of a female Stegodyphus appears to be a life of endless suffering.

Somehow, somehow, it is all worth it. It is not by accident that nature selected this all-eggs-in-one-basket scenario. If the first clutch of eggs is a success, it's a big success. The spiderlings may be making a meal out of their very own mother, but by the end of the feast they will grow three times in size. Each clutch has plenty of eggs and their mother’s sacrifice ensures that every egg has a very high chance of survival. This is a reproductive triumph. 

Paternal Costs and Benefits

It’s rather frustrating that this is also a triumph for whoever fathered those eggs - and then promptly left without a care while the mother liquified herself. The father puts the most effort into the parenting process when he dances around to create certain vibrations on the web that make a female want to mate. But to be fair to him, it's a brutal race to be a “first-clutch father”. The timing of sexual maturity of male and female spiders doesn’t line up very well. By the time many females have laid their eggs, a sizable number of males in the population have just become ready to mate. As with many other species on the planet, females are the limiting factor and it is highly unlikely that a late-bloomer will find a female that hasn’t mated yet. And so, males resort to discarding the eggs of females who have already mated. They know that bereaved mothers have little choice but to mate with them - despite the incredibly violent intrusion into her home. 

Of course, beyond the purpose of anthropomorphic humor, moral judgements do not serve us well in the understanding of such extreme parenting. The Stegodyphus parents are both doing exactly what they need to do to pass on their genes most effectively - in their specific circumstances, in their specific environment. And despite their vastly different strategies, their common goal of successfully producing the next generation is often achieved.

Strategies Based on Sex

For many, the most fascinating aspect of Stegodyphus parenting is just how different the mother and father are. Specifically, how much more the mother invests in their children. Let’s be clear - every living thing on the planet invests something in parenting. Even a unicellular bacterium halves it’s cytoplasm (and all the important proteins inside it) when it divides into two daughter cells. But the Stegodyphus mothers and fathers show us how varied both the degree and mechanisms of parental investment can be. The primary concern of the Stegodyphus father is to make sure he is the parent. He scouts out new mates, scurries around to knock off egg sacs, heaves a large and heavy egg sac to the edge of the web - males invest a lot of effort  to secure as many heirs to their throne as possible. Females of the majority of animal species are relatively less concerned about ensuring that they are the parent. After all, the eggs or live young are usually coming from her body - which leaves little doubt. The primary concern of the Stegodyphus mother is to make sure the offspring survive. She invests everything she has (quite literally) in their nutrition, their strength, and their first home. 

Millions of animal species follow this pattern of sexed parental investment (Scientific American 2011). Mother lions hunt the food that feeds cubs while father lions sit and look tough - occasionally roaring at animals in their territory, and then settling down for a nap. Grizzly bear mothers forage for their young, taking care not to settle down too close to their father - because he may eat his own cubs if he is hungry enough. There are exceptions of course, but this is a clear and common pattern. Females, with their precious few eggs and investment in pregnancy, have evolved to be successful parents who invest in the survival of their offspring. Males, with their abundance of sperm and freedom from pregnancy, have evolved to focus their efforts on becoming a parent in the first place. 

What About Us?

Humans can hardly claim that we have more equality in our sexed division of parental investment. Progress has been made over the past few millennia but remarkable disparities still exist. When the average heterosexual American couple become parents, mothers will likely spend twice as much of their time looking after a baby than the father will (Schoppe-Sullivan 2017). When the modern American father cares for his children, he often has the luxury of doing just that. Mothers spend an average of ten more hours a week multitasking during childcare. This means looking after a child while doing housework, while doing paid work, and while taking care of herself. Some disparities in parental effort are more difficult to measure. Mothers report that they are more often carrying the burden of “worry work” - the mental care of children that's rooted in first planning their lives, then remembering, and finally reminding. The frequently-spouted counter argument to this understanding of sexed parental labor is that fathers do parent - by providing financially for the family more than mothers do. If so, why would the data show that these inequalities have absolutely no statistical correlation with the number of paid working hours of either parent?

The movements of feminism and LGBTQ+ rights have done incredible work to address many of these disparities by rethinking the gender roles they are based on. Some heterosexual couples have completely reversed the traditional sexed division of labor. Some couples divide their labor as equally as possible. Some others are perfectly content without children. But the data is clear: modern heterosexual couples all over the world still continue to partake in much of the inequalities that we see elsewhere in the animal kingdom. Are we receiving any evolutionary benefit from this inequality? 

The nature of most human societies today means that fathers do not benefit evolutionarily from decreasing their parental efforts. Of course there are exceptions - but the vast majority of fathers on Earth are not having so many children with so many women that they have an evolutionary excuse for spending less energy and effort on parenting. Even if you were to ignore the moral arguments for equality in parenting - it is still difficult to ignore that unlike the Stegodyphus spiders, lions, and grizzly bears we have no evolutionary reason to parent the way we do. The sex-divided parents of the animal world have something to teach us. They remind us of the evolutionary principles that govern the division of parental investment. And when we apply those principles to ourselves we see that our inequalities are not natural. We created them. We perpetuate them.

Friends With Benefits

The Chacma Baboons

Humans may be the ones responsible for the phrase “you scratch my back and I’ll scratch yours,” but our primate relatives are the ones who practice it most literally. Chacma baboons are among the largest primates in the world. They are remarkably aggressive animals. A pair of them can successfully chase away a cheetah. These same baboons will also sit pretty in front of one another, running their fingers through the fur on a fellow baboon's back, looking for insects, twigs and leaf matter, or other debris (Reed Education 2008). But the true purpose of this behavior is of course not actually hygiene. Grooming is social. Grooming is the behavior that facilitates a spirit of reciprocity, even camaraderie. Genuine friendships are born by simply sifting through each other's fur for hours on end. Friendship - and this is as scientific as it is cheesy - is the foundation upon which an incredibly complicated society of Chacma baboons is built. 

True friendship between males and females though, is rare in the animal world (and, to be fair, parts of the human world as well). But it is common among Chacma baboons. Particularly among males and lactating females (Moscovice 2009, 1472). To be clear, there are male Chacma baboons and lactating mother Chacma baboons with children from another father, who form a genuine friendship while she is nursing. 

Are male Chacma baboons just … incredibly chivalrous? 

Male Friendship and Children

A population of Chacma baboons in the Moremi Game Reserve in Botswana has been extensively observed since 1978. The friendship between male Chacma baboons and lactating mother Chacma baboons is quite famous (at least in ecological circles) but the actual impact of this friendship on the children used to be a mystery.

It turns out that male friends actually had the same impact on children that one would expect of a biological father. Of course, if the father is around (only true for one third of the children in the study), they are the primary male caretaker. But the male friend is still around - and quite involved - in ways that are very similar to the biological father himself. 

But how prevalent were these “male friends”? Every adult male who was present in the population at the time of conception was a male friend who accompanied anywhere from one to seven young Chacmas. In fact nearly three-fourths of the young baboons lived with these male friends at least for some time. This behavior was universal.

But is this parenting or mere companionship? The difference between the two is the presence of specific, direct investment. Fights happen quite regularly in primate societies, especially attacks on weak children. The aggressor could be an alpha male, another Chacma child, an adult female - anyone is ready to pick a fight when resources are scarce. Male friends intervened, often saving a child’s life, more often than biological fathers did.

The Logic behind Male Friendship

Parenting behaviors as selfless as this one make the argument for altruism quite seducing. But of course, this behavior must somehow allow a male friend to pass on his genes - otherwise it could not have become so widespread in the population. Biologists seek parsimony - the simplest solution to an evolutionary puzzle. And this process often starts with a cost-benefit analysis.

It turns out that these parenting behaviors appear incredibly costly specifically because it's all for someone else’s child. Though a male friend is often intervening in fights on a child’s behalf, the vast majority of these fights are with baboons that are likely to be smaller in size. The friend loses energy but rarely loses blood when up against a younger adult male, a female baboon, or other children. If, for just a moment, we erase the biological relationship (or lack thereof) between the male friend and the children from our minds - this parenting behavior is not so costly after all.

Of course behaviors are not passed on through the generations because they are only a little costly. Evolution is dependent on a profit motive. The question to answer now is - What is the benefit?

Chacma baboon societies are multi-male and multi-female with both males and females being sexually promiscuous. In a month long estrus cycle, a female can mate multiple times, with multiple males (Animal Diversity 2004). The most important requirement for successful mating is her cooperation. Aggressive males may push other males out of way - but by the time they get to her, if she’s not willing, all their effort is for nothing. Females decide who wins the fight to reproduce.

And this is precisely where the male “friends” come in. In the current mating period, new mothers need their male friends to be with the children. They are, quite literally, in the friend zone this time around. But when the next mating period comes along - females will recall this friendship. And so, what was once a friendship becomes something more. Male friends will be at the front of the line the next time their female friend is ready to mate. Time-consuming means truly justify the ends for the friend-turned-partner Chacma baboon.

It Takes a Village

From the children’s perspective, it doesn’t really matter why male friends do this. It's just incredibly beneficial that they do it. There are a lot of other ways that males could have caught female attention. But this specific behavior evolved because of the power of reciprocity. When the male cashes out on all his female friendships and becomes a prolific father, his children will rely on the affections of other male friends. This culture of male friendship benefits everyone. The saying “it takes a village” stands true - in human societies and in animal ones.

 There is somewhat of a conflict in this arena of evolution - a conflict between the perspectives of selfish survival and angelic altruism. It is often resolved by group selection. Male Chacma baboons who look after unrelated offspring, humans who babysit for a work friend, or older female elephants who guide a young calf - all incur a short-term cost. But the chance of survival is higher for a group of baboons, humans, and elephants who do these things for one another than it is for a group who do not. The evolutionary principle of reciprocity allows a remarkable amount of parental investment from individuals who are not the parents themselves. This is so widespread that it has a name: alloparenting. 

Meerkats, wild dogs, and wolves have one thing in common (at least the females do). Females who are not pregnant will undergo a “pseudopregnancy.” Their bellies and mammary glands swell as if they were going to give birth (Natural History 2009). Magpie jays who have barely even reached maturity will fly back and forth to a nest to bring back many beakfuls of food for baby chicks who aren’t their own. Golden lion tamarins are assisted in the process of motherhood by alloparents who bring back extra food from their travels and even carry young tamarins around. Throughout the animal world, the cost of alloparenting is offset by the benefit of children who are fitter, smarter, and more successful.

Our Nuclear Families

Humans also have an instinct to care about the children of other humans. But there is also a strict delineation of responsibility to the “true” parents. This narrow perspective of who is responsible for parenting is especially prevalent in Western society. Scholars agree that the concept of a rigid nuclear family took hold in America in the 1960s - and took hold so deeply that it seeped into nearly every facet of our lives (Brooks 2020). It changed the very way we think about parenting. In modern America, mothers and fathers (but most often mothers) are often shamed for handing off child care responsibilities to others too often. And this has an impact on what we think of families of color - which often operate quite differently even in Western environments. If a White social worker sees a Black or Latinx child moving between their parents’ house, their grandmother’s condo, and their older cousin’s apartment - this could be reported as a sign of instability. Grandparents taking care of children “too much” is almost automatically a sign of some level of parental neglect - because grandparents are not the parents. And the idea of community parenting, where complete strangers care for each other’s children, is largely associated with hippie communes of the 1960s and 70’s. The concept of alloparenting is now permanently marked with the stains of neglect and social deviance in the White Western world.

Of course, even in a society where nuclear family parenting is the norm, children can still have multiple parental figures. A child of nuclear family parenting may still have parental figures at school, at a religious institution, or among extended family members. But the most important product of nuclear family norms are the legal and societal frameworks that come with it. In most Western countries this complexity of parental relationships will not be reflected in medical access, academic records, or social work procedures (Brooks 2020). 

The bureaucratic domination of the nuclear family may have solidified in the White Western world in the latter half of the 20th century. But did it stay there? From India to Egypt to Panama, more than a dozen countries show a statistically significant trend to a dominance of nuclear families above all other family structures (United Nations 2006). It is reasonable to predict that this trend will be followed by a similar shift in the legal mechanisms of parenthood. And this trend is suspected to be even more widespread - many countries simply lack the comprehensive census data it takes to see it. 

What’s curious is that this increasingly global parenting philosophy is not at all the natural state of humankind. In modern day foraging societies, which we often assume approximate most ancient forager societies, a baby is cared for in some way by an average of twenty other people every day (Natural History 2009). Modern day humans are somehow simultaneously at the pinnacle of child care resources and at a record low of the quantity of parental figures in our lives. Returning to our ancestral roots of community parental investment requires shattering the barriers of economic callousness and cultural stigma - but both evolution and history tell us that it would be worth it.

Where Do We Go From Here

We’ve looked at just two animal stories: the Stegodyphus genus of spiders and the Chacma baboons. And both of them demonstrate pertinent and powerful evolutionary principles. One: sexed parental investment evolves when males and females achieve significant evolutionary benefit from different parenting strategies. Two: alloparenting is costly but benefits everyone’s evolutionary success because of reciprocity. Modern humans are rarely benefiting from sexed parental investment - so the moral argument for equality in parenting has tremendous evolutionary support. Modern humans used to benefit from alloparenting (and still do in many societies), but many humans have favored a more rigid parenting style where there are far fewer parental figures invested in each child. These are already two remarkably powerful conclusions - conclusions that can make us better parents - and better people too. 

But so many more animal stories await exploration. The miniscule father strawberry poison dart frog urinates on his own children to keep them hydrated (BBC 2015). Galapagos seal mothers drop their children off at a “nursery” where the children can be watched by a rotating staff of other female seals. Giant Pacific octopus mothers tend to 100,000 eggs at once.

Every single one of these parenting strategies evolved for a reason. And every single one of them means something for evolution, for us. We will likely never become the best parents we can be if the entire discussion occurs in our human bubbles - with equally confused parents talking in circles. We need science. We need the beings we share this planet with. And we need to remember that we are not quite as special as we think we are.