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Who Invented Inventions?

This occurred 3 million years ago, which is before humans evolved.

3 million years ago

The invention of inventions

In October 1960, a then twenty-six-year-old Jane Goodall observed a chimpanzee she dubbed David Greybeard strip a long twig of its leaves, use it to probe a termite mound, and lick away the bugs he retrieved. It may have been just a snack for Greybeard, but to a scientific community who at the time defined Homo sapiens by their unique use of tools, it was earth shattering. Goodall immediately telegraphed the news to the paleoanthropologist Louis Leakey, who famously responded, "Now we must redefine tool, redefine man, or accept chimpanzees as human."

After some scrambling among anthropologists to redefine the uniqueness of our species, they landed upon our ability to use tools to make other tools. David Greybeard may strip away the branches of his termite dipping-stick, but only hominins (a catchall word that refers to H. sapiens and all of our extinct ancestors after the split from apes) could invent a special branch-stripping tool. Many archaeologists I spoke with believe the ability to plan and solve a problem using a complex device does not merely define our species, but in a few instances made our species. Our inventions aren't the result of our evolution, they believe, but are instead the explanation for the route it took. In at least a few cases, the earliest first inventors did not merely enable a new way of life or allow new economic possibilities, as we would modernly think of a modern invention, but instead enabled our evolution.

In no case is this truer than in that of the very first invention of all, made by an ancient ancestor of ours long before H. sapiens evolved.

Who was the first inventor?

I'll call her Ma, because she was a young mother, who like all inventors, had a problem.

Ma was born approximately 3 million years ago and belonged to an ancient ancestor species of ours called Australopithecus. She was born in Africa, perhaps Eastern Africa, where archaeologists have discovered a concentration of australopithecine fossils, including the famous "Lucy" found in 1974. Three million years ago is approximately halfway from the time when our species first split from the chimpanzee and bonobo line to the modernday, so it's no surprise that in appearance and behavior, Ma represents a middle ground between H. sapiens and chimpanzees.

She stood almost four feet tall, weighed a lithe sixty-five pounds, and other than on her hairless face she was covered in thick dark fur. Ma ate more meat than a modern chimp does, but she scavenged it rather than killed it. Ma supplemented her meals with roots, tubers, nuts, and fruits. In many respects, a modern observer might mistake her for a remarkably well-balanced, walking chimp, save for her peculiar, dexterous, and inventive use of rocks. To aid her work scavenging carcasses, Ma sharpened stones to cut into bones for marrow, which allowed her to eat meat other scavengers couldn't access.

Ma was a clever ape, but to many of Africa's big cats, she was still lunch. During the day she walked upright in search of food, but at night she clambered back into a tree nest to avoid nocturnal predators. Archaeologists have found australopithecine femurs and arm bones in caves adjacent to complete predator skeletons, which is a clear but grim signal of who was eating whom.

The predators interested in Ma were varied. She lacked fire and as a result found herself particularly vulnerable to a hunter similar to the modern panther, but she occupied a rung so low on the food chain that even eagles made the occasional meal out of australopithecines.

Her inability to start and control fire had a far more significant implication: It meant she ate her food raw.

The digestive system extracts fewer calories from uncooked food than raw and it is far more difficult to chew, which means Ma had to spend more time gathering and eating than a modern H. sapiens. Even with their large teeth and strong jaws, modern chimpanzees spend up to six hours per day chewing their raw food, while the average modern person's cooked diet allows them to eat a day's rations in a brisk forty-five minutes. Ma's raw diet meant she would have had to spend nearly her entire day gathering food and eating it while dodging eagles and panthers, clambering up and down trees, and roaming across open ground looking for carcasses and fruit.

All of which would have become far more difficult when, in her early teens, Ma gave birth to a noisy, helpless, immobile infant.

H. sapiens infants are an evolutionary curiosity. Most mammalian babies are born ready to walk, trot, or at least hold on to their moms. The reason is blindingly obvious: Every day a baby spends unable to keep up is life threatening for both mother and child. A capuchin monkey's baby can grip its mother's fur almost immediately, while the bigger-brained chimpanzee's mother has to carry her newborn, but only for its first two months. H. sapiens babies, on the other hand, spend more than a year in almost complete helplessness, unable to walk, crawl, or even support their own body weight. While this would seem an evolutionary disaster, it is the downside to what is perhaps our greatest strength: oversize brains. Our extended weakened state is partially explained by the time required to develop trillions of synaptic connections within our brain. In all primates, an evolutionary trade-off occurs between larger brains and infant mortality, and each species has arrived at its own equilibrium. The question archaeologists have asked is how humans arrive at such a perverted one.

Presumably, when hominins first branched off the chimpanzee line, hominin babies could soon cling to their mothers. Yet at some point this began to change. When I asked Cara Wall-Scheffler, a biologist at Seattle Pacific University, when young hominin mothers would first have been strained to the breaking point by their helpless babies, she said she believes the switch to bipedalism nearly 3 million years ago would have placed mothers and their newborns in a dangerous position.

Her reasoning is straightforward: Walking upright would have made it far more difficult for a baby to cling onto its mother. In addition, upright walking requires narrow hips, which would have narrowed the birth canal and necessitated smaller-headed babies. But instead of hominin heads shrinking, and hominin babies becoming more capable, the exact opposite occurred. Head size increased, and babies became even weaker. Today, H. sapiens have one of the largest body-to-head-size ratios in the animal kingdom despite walking upright. It's an oddity biologists call the smart biped paradox.

The evolutionary explanation for the paradox is that hominin mothers like Ma birthed their babies earlier in their gestation. Essentially, Ma's baby was born two or three months premature, before its head could outgrow the exit. Since Ma, the change has only become more pronounced. If H. sapiens birthed babies at the same developmental stage as chimpanzees, pregnancy would last twenty months. Not only would a baby that large not fit the birth canal, but the strain on the pregnant mother would be far too great. The result is that a human baby's first seven months are spent as if it were still in the womb-helpless and completely dependent on its mother-while the baby adds more than a billion synapses to its brain every minute.

MaÕs helpless baby would have posed the greatest challenge to her while she gathered food. No modern primate species, with the exception of ours, shares parenting duty, so she is unlikely to have received help from the father. Nor is she likely to have even set her child down for longer than a few moments, because no primate in the wild ever parks their baby. ItÕs simply too dangerous. If Ma left her baby while she gathered food, her babyÕs reaction would have been quite like what you would hear from a human baby in a similar situation today. Eventually, her baby probably wouldnÕt have been there when she returned.

The cumulative evidence suggests that Ma would have had to carry her baby for at least its first six months of life while spending most of her waking hours searching for food. The exertion of energy alone would have been life threatening. Wall-Scheffler looked at the ergonomics of the baby-carrying problem an australopithecine mother like Ma would have faced, and concluded she would have expended 25 percent more energy than usual while carrying her baby-far exceeding the already significant cost of nursing. In her estimation, carrying a baby is so taxing, bipedalism itself would have necessitated a solution.

Ma's solution, Wall-Scheffler tells me, was the astoundingly revolutionary, species-altering idea to not only invent something, but invent what is probably the most consequential tool of all time.

She invented a baby sling.

The materials of Ma's sling would have been basic. Perhaps as simple as a single loop of vine wrapped and tied off in a knot. While a knot-tying may seem advanced for an australopith like Ma, all great apes can tie knots, and as Wall-Scheffler told me, it therefore "doesn't seem outside the realm of possibility that australopiths would have been able to make a simple loop."

The baby sling therefore may not have been as much of a technical challenge as a conceptual one. Using a tool to make another one involves what psychologists call "working memory," which simply means the ability to hold information in your mind, manipulate it, and then use it.

Working memory is something we employ all the time-for example, when you shop at the grocery store, you might visualize the dish you're going to make so you can buy the necessary ingredients. Or if you're completing a puzzle, you might visualize what it's supposed to look like so you know where a given piece should go. The more steps that are involved in a given task, the more working memory is required. Building a rocket part that has a complicated interplay with thousands of other components requires more brain power than shopping for dinner, but the principle is the same. Ma couldn't build a rocket, but when her baby weighed heavily upon her and she visualized a potential solution, she demonstrated the early beginnings of a sophisticated psychological trick.

Ma's sling may have made her life only slightly easier, but its evolutionary consequences are difficult to overstate. A simple sling would have allowed hominin babies to spend a nearly unlimited amount of time in a helpless state, which, according to archaeologist and author of The Artificial Ape, Timothy Taylor, didn't just alter the smart biped paradox, it threw it out entirely. The paradox doesn't exist if mothers, armed with slings, can birth their babies long before they would otherwise be developmentally ready. A baby sling didn't just ease Ma's burden. It removed the evolutionary governor on how large our brains could grow. In doing so, the baby sling altered our evolution.

It sounds hyperbolic. It isn't. Without baby carriers, helpless hominin babies would have been set down by tired mothers and picked off by panthers long ago. According to Goodall, inexperienced chimpanzee mothers lose half of their babies while they're unable to hang on. And that's in only two months. Large heads on bipedal creatures should be an evolutionary dead end. The fact that it isn't is thanks to the baby sling. And to Ma.

Of course, if Ma had been the only one to use a baby sling, and if her fellow australopithecine mothers had given her invention no more than a quizzical look, the evolutionary consequences would have been nil. She would have made her life slightly easier and nothing more.

But that's not what happened.

Ma's invention spread. Shortly after Ma, according to Taylor, our ancestors experienced a burst of rapid brain growth. This dramatic growth, which resulted in mothers birthing babies even earlier in their development, would have been impossible without her sling. And if Ma's idea spread, then it suggests that australopithecines already possessed the beginnings of what might be H. sapiens' greatest skill: We are a species of incredible copiers.

Anthropologists call this skill "social learning," and when researchers have tested H. sapiens newborns against chimps in a variety of intellectual challenges, social learning is the skill at which humans exhibit far more talent. According to the Harvard University professor of human evolutionary biology Joseph Henrich, H. sapiens are habitual mimics. We watch each other, we learn, and we copy. Essentially, we are a species of shameless intellectual plagiarists. But this is a feature, not a bug.

None of us are as terribly ingenious as we might like to think, particularly when it comes to our survival. As Henrich notes in his book The Secret of Our Success, stranded groups of human explorers who have found themselves shipwrecked or abandoned in the deserts of Australia or on the frigid tundra of Greenland have a wretched record. In nearly every case, explorers lost in novel environments either accept help from locals or starve to death in their ignorance.

The lesson, according to Henrich, is that we owe our incredible adaptability to humanity's ability to learn, copy, and compound small innovations. If humans, like apes, largely ignored each other's moments of inspiration, we might still be stuck in the same environmental niche. But thanks to our relentless excellence in mimicry, we aren't. Each small improvement by each individual is monitored, learned, and adopted by the group. We are the technological ratchet machines of the animal kingdom. Through micro innovations and collective plagiarism, we progress.

By the time of Ma's invention, hominins' great mimicking ability seems to have already existed, because her fellow australopithecines did not ignore or mock her curious contraption. They did what hominins do best: They copied it.

Not only did the wide adoption of the sling artificially extend gestation and remove the upper limits for how large our brains could become, it tightened the bond between mother and child. The sling physically attached a mother and child in such a way that they could look at each other for long periods of time. And while Ma did not speak a complete language, she could almost certainly, like chimpanzees, communicate on a simple level.

Goodall has recorded communication between chimp mothers and their babies, and their calls largely consist of vocalized "hoos" when a baby wants a ride or the mother wants them to climb aboard. While this is nothing like the constant chatter that occurs between a H. sapiens mother and her newborn, the increasingly frequent hoos Ma cooed at her newborn may have been a precursor to something much more sophisticated. "Motherese"-the melodic way in which a mother speaks with her infant, also known as baby talk, e.g., "Aren't YOU a GOod GIrl"-is a cultural universal. All human mothers of all languages speak to their babies in the same rhythmic HIGH-low-HIGH pattern, suggesting to anthropologists that this way of communicating stretches deep into our past. Some linguists even believe baby talk is an echo of the original tongue, developed long before language evolved. As Ma knotted the first sling and spent her days looking into the eyes of her infant, she may have unintentionally strengthened the critical bond between mother and child forever.