Jakarta –
Humans have a much longer childhood than great apes, such as chimpanzees and gorillas. At this time the adults around them, such as parents, grandparents and other family members play an important role in children’s physical and cognitive development.
The long growing period of childhood provides more time to master the social and cognitive skills that humans need to carry out daily life.
Today, scientists say that long childhoods are the result of human brains growing larger. However, based on the results of the latest research, this hypothesis needs to be updated based on the fossil teeth found.
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Research Process That Took 18 Years
This study was carried out by a combination of researchers from the University of Zurich (Switzerland), ESRF, and the National Museum of Georgia (Georgia) who used synchroton imaging technology to study early Homo fossil teeth found at the Dmanisi site, Georgia.
It is estimated that the fossil is around 1.77 million years old. Now this study has been published in the journal Nature.
“Childhood and cognition cannot be fossilized, so we rely on indirect information. Teeth are ideal because they are well preserved and have growth structures that record daily development, much like the annual rings on a tree,” explained researchers from the University Zurich and the study’s lead author, Christopher Zollikofer.
The research took nearly 18 years, starting in 2005 and published in 2023. The synchrotron imaging technique the scientists used created virtual microscopic slices through fossil teeth and allowed them to accurately study tooth growth in detail from birth to death.
The results showed that the early Homo individuals studied died between the ages of 11 and 12 years. Based on data evidence, it appears that his wisdom teeth have grown. This is similar to development in great apes, which also undergo similar growth at the same age.
However, what is interesting is that the pattern of tooth development in this fossil shows similarities to modern humans. With the back teeth growing behind the front teeth during the first five years of development.
This suggests children of early Homo species used primary teeth longer than great apes and they relied on adult support for longer periods.
“This could be the first evolutionary experiment on extended childhood,” said Marcia Ponce de León from the University of Zurich, quoted from the European Synchrotron Radiation Facility.
The Relationship between Fossil Teeth and Brain Evolution
This research challenges the long-held “big brain-long childhood” hypothesis. In early Homo individuals, their brains were not much larger than those of great apes or Australopithecus.
However, they may have a longer lifespan. This is as demonstrated by the discovery of the skull of an old individual in Dmanisi who survived without teeth for the last few years of his life.
“The fact that this very old individual was able to survive without teeth for several years suggests the rest of the group took good care of it,” said David Lordkipadnize of the National Museum of Georgia.
This research highlights the importance of a three-generation social structure, in which adults and the elderly help care for children. This allows the transfer of knowledge between generations which plays an important role in the development of human culture.
“Older individuals are those who have the most experience. It is likely that they played an important role in the development of human culture,” explained Lordkipandnize.
Extended Childhood Favors Brain Evolution
This research provides a new hypothesis, it is not just an increase in brain size that causes a slowdown in human development. However, the length of childhood allows for more effective cultural transmission.
The more information that has to be memorized, the longer it takes to process it. As a result, childhood lasts longer. This process would increase the capacity to learn and develop complex behavior and provide an evolutionary advantage in survival.
As the amount of information that needs to be learned increases, evolution drives brains to become larger and adulthood to become slower. This allowed humans to learn more during childhood and develop larger brains despite limited food resources.
(nah/nah)
(clears throat) Ah, the joys of childhood. You know, that magical time when you’re not quite sure what’s going on, but you’re pretty sure it’s not your fault. (chuckles) Well, it turns out that our ancestors had a rather… extended childhood, if you will. (smirks) I mean, who needs to grow up quickly when you’ve got adults around to feed you and wipe your nose, right?
According to this fascinating study, early Homo individuals had a rather lengthy childhood, much like us modern humans. But, unlike us, they didn’t have the benefit of, say, an iPhone to keep them occupied. (laughs) No, no, they had to rely on their own two feet and a lot of adult supervision. I mean, can you imagine? “Mum, I’m bored.” “Well, go gather some berries, dear.” (chuckles)
Now, you might be thinking, “But what about brain development? Don’t we need big brains to, well, be human?” Ah, yes, well, it turns out that’s not entirely the case. (smirks) It seems that our ancestors’ brains weren’t much larger than those of great apes or Australopithecus. But, they did have something that those guys didn’t: a longer lifespan. And, let’s be real, that’s basically just a fancy way of saying they had more time to figure things out. (laughs)
The study found that early Homo individuals had a rather unique tooth development pattern, which suggested that they relied on adult support for longer periods. (smirks) Ah, yes, the classic “I’m not lazy, I’m just conserving energy” approach. (chuckles) But, in all seriousness, this does highlight the importance of a three-generation social structure, where adults and the elderly help care for children. It’s like that old saying: “It takes a village to raise a child.” (smirks) Or, in this case, it takes a village to raise a child who’s still learning how to use a rock. (laughs)
Now, I know what you’re thinking: “But what about the ‘big brain-long childhood’ hypothesis?” Ah, yes, well, it seems that’s not entirely accurate. (smirks) It turns out that it’s not just about having a big brain; it’s about having the time to learn and develop complex behavior. And, let’s be real, that’s basically just a fancy way of saying we’re all just winging it until we figure things out. (laughs)
In conclusion, it seems that our ancestors had a rather… relaxed approach to childhood. (smirks) I mean, who needs to rush into adulthood when you can just take your time and enjoy the ride? (chuckles) But, in all seriousness, this study does highlight the importance of social structure and learning in human development. So, the next time you’re feeling stressed about your kid’s development, just remember: they’re not lazy, they’re just conserving energy. (smirks) And, if all else fails, just give them a rock to play with. (laughs)
Jakarta
Humans possess a remarkably prolonged childhood compared to great apes, such as chimpanzees and gorillas, a phenomenon attributed to the vital role adults play in fostering children’s physical and cognitive development. Over an extended period, children master intricate social and cognitive skills essential for navigating daily life, setting humans apart from other primates.
This extensive juvenile growth phase is often associated with the evolution of larger brain sizes in humans, but new research findings suggest this correlation may require reevaluation in light of recently examined fossil teeth discoveries.
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An 18-Year Journey of Discovery
A collaborative research effort between the University of Zurich (Switzerland), ESRF, and the National Museum of Georgia (Georgia) leveraged cutting-edge synchrotron imaging technology to scrutinize ancient Homo fossil teeth unearthed at the Dmanisi site in Georgia. Estimated to be approximately 1.77 million years old, this crucial finding has recently been published in the esteemed journal Nature.
“Childhood and cognitive development, though not directly fossilizable, can be inferred through indirect evidence. Fossil teeth, being exceptionally preserved and possessing growth structures that chronicle daily development, serve as ideal substitutes,” noted Dr. Christopher Zollikofer, lead researcher from the University of Zurich. "
The meticulous research process spanned nearly two decades, commencing in 2005 and culminating in publication in 2023. Employing synchrotron imaging techniques, scientists meticulously crafted virtual microscopic cross-sections of fossil teeth, thereby allowing them to meticulously examine tooth growth from infancy to adulthood with unprecedented precision.
The study revealed that early Homo specimens perished between 11 and 12 years of age, as evidenced by the presence of wisdom teeth. Interestingly, this developmental pattern parallels that observed in great apes, which also exhibit similar growth milestones at comparable ages.
Notably, however, the fossilized teeth exhibited similarities in development to modern human teeth, characterized by the rear molars emerging behind the front teeth during the initial five years of growth. This unexpected finding suggests that early Homo juveniles retained primary teeth for extended durations and relied on adult support for longer periods, which might signify the first evolutionary experiment with prolonged childhood.
Unraveling the Enigma of Human Cognition and Fossil Teeth
This groundbreaking research directly challenges the established “big brain-long childhood” hypothesis, which posits a direct correlation between human brain size and childhood duration. The researchers found that the brains of early Homo individuals were relatively comparable in size to those of great apes and Australopithecus. Nevertheless, they likely boasted longer lifespans, as exemplified by the remarkable discovery of an elderly Homo skull in Dmanisi, which revealed the individual had survived for several years without teeth.
“The fact that this elderly individual managed to survive without teeth for an extended period underscores the possible presence of a caring community, where adults and the elderly provided sustenance for the young,” observed David Lordkipanidze from the National Museum of Georgia.
This study underscores the significance of a three-generation social hierarchy, where adults and elderly contribute to childcare, facilitating the intergenerational transmission of knowledge. This structure, pivotal to the emergence of human culture, allows seasoned individuals to play a crucial role in shaping cultural development.
The Prolongation of Childhood: A Catalyst for Brain Evolution
This research offers an innovative hypothesis: the prolongation of childhood, rather than merely an increase in brain size, sparks a slowdown in human development, favoring the efficient transmission of cultural knowledge. The more complex the information to be absorbed, the more time-consuming its processing becomes, thus extending the duration of childhood. Consequently, this mechanism enhances learning capacity, cultivated complex behaviors, and bestows an evolutionary edge in survival.
As the quantity of information required for learning increases, the evolutionary drive for larger brains and more gradual maturation intensifies, ultimately allowing humans to absorb more knowledge during childhood and develop greater cranial capacity despite resource limitations.
