New research into ancient hominin development suggests that Neanderthal infants grew at a significantly faster rate than modern humans (Homo sapiens ), possessing much larger bodies and brains for their age.
A detailed anatomical study of a rare Neanderthal infant skeleton, known as Amud 7, reveals a striking discrepancy between dental aging and physical growth. While the infant’s teeth suggest a biological age of only about six months, its bone length and brain development more closely resemble a modern human child aged 12 to 14 months.
The Amud 7 Discovery
The specimen, discovered in 1992 near the Sea of Galilee in Israel, dates back to between 51,000 and 56,000 years ago. Because specimens of young Neanderthals are incredibly rare, Amud 7 provides a critical window into the species’ life cycle.
Researchers at Ono Academic College, led by Ella Been, analyzed the skeleton through microscopic scans of dental structures and bone measurements. Their findings suggest a pattern of “asynchronous” growth:
– Dental Age: Approximately 6 months.
– Skeletal/Brain Age: Approximately 12–14 months.
A Consistent Biological Pattern
This was not an isolated case. When researchers compared Amud 7 to two other Neanderthal remains—Dederiyeh 1 (a 2-year-old from Syria) and a 3-year-old specimen from France—they found a consistent trend. This repetition suggests that the rapid physical growth of Neanderthal toddlers was a defining biological trait of the species rather than an anomaly.
According to the research, Neanderthal development followed a unique three-stage trajectory:
1. Infancy: Newborns experienced dental and bodily growth in relative sync.
2. Toddlerhood: A massive surge in body and brain growth occurred, outpacing the development of the teeth.
3. Childhood: By roughly age seven, dental and skeletal growth synchronized again, though brain development remained rapid.
Why Did They Grow So Fast?
The primary question raised by this study is why Neanderthals underwent such intense developmental pressure. Scientists believe this rapid growth was a necessary evolutionary adaptation to harsh environments.
“In the first few years of life, from birth through early childhood, Neanderthals grew faster than modern humans.” — Ella Been, Ono Academic College
There are two main drivers behind this theory:
* Thermoregulation: Larger bodies retain heat more efficiently than smaller ones. Rapidly reaching a larger size would have helped Neanderthal infants survive the cold climates of Eurasia.
* Energetic Demands: This accelerated growth required significantly more caloric intake, implying that Neanderthal caregivers had to provide high-energy resources to support these “high-speed” developing children.
Conclusion
The study of Amud 7 demonstrates that while adult Neanderthals were somewhat similar in size to modern humans, their childhoods were biologically distinct. This rapid growth phase served as a vital survival mechanism, allowing them to quickly reach a size capable of enduring much colder and more demanding environments.
