What does the morphology of Homo sapiens and Neanderthals tell us about the Neanderthal extinction?
The cartoon above shows the typical "Neanderthals were less intelligent" notion, but it also carries the underlying tone that they were less intelligent due to their morphology and physiology. Let me start by getting the "boring" stuff out of the way. In order to be able to process how the morphology of early hominids has affected the development of culture, artistry, and everyday lifestyle practices, we must look at the straight facts: What are the morphological features of Homo sapiens and Neanderthals? How are they similar, and how are they different?
Morphological Features of Homo Sapiens (Anatomically Modern Humans):
Cranial Features:
Post-Crania Features:
The short video above shows how scientists recreate a Neanderthal man from skeletal remains.
Now for the fun stuff. . .
Everything I just mentioned is, in the grand scheme of things, simple facts that only help us understand the complexities of early hominid existence. What I am truly interested in is how these morphological features played into the development of symbolic practices, such as hunting and burial practices. More importantly, did any of these morphological features have an impact on the Neanderthal extinction?
It is commonly known that Neanderthals are very well adapted for cold climates, which is also in accordance with Bergmann's and Allen's rules. They had wider noses to heat the cold air before it enters their lungs, and their heavy brow ridges protect their eyes from the sun. So, in terms of hunting practices that developed out of these skeletal traits, we often see the pattern of injuries among Neanderthals resemble those of rodeo performers, which suggests that they hunted with weapons that required them to get close to very large animals. We know this from our previous discussion of lithics.
Since some Neanderthals apparently lived a long time after serious injuries, such as tooth loss, partial paralysis, and severe broken bones, it has been suggested that Neanderthals potentially took care of the sick, injured, and old. For example, at La Chapelle-aux-Saints there was a specimen found that was and old male (roughly 45), with incapacitating arthritis of jaw, back, hip, and almost no teeth. There is also evidence of an old man being taking care of at the site of Shanidar. This old man had crushed eye orbits, and was most likely paralyzed. However, yet evidence of atrophy and healing showed on the bones, which tells us he was most likely cared for.
In Homo sapiens, there are many more instances of symbolic practices being used. This is potentially because cognitively modern Homo sapiens would have had more "old, experienced people around than did previous hominids. This might have increased their ability to accumulate experience and knowledge, and for younger individuals to learn from older ones, encouraging varied local cultures and more rapid cultural change." (Source: Owen College. (2008). Neanderthals and homo sapiens. Owen College. Retrieved on November 12th, 2012, from bruceowen.com)
The evidenced just discussed points out that there were obvious instances of lifestyle practices that developed out of the specific morphology of Neanderthals, but it doesn't really point to any good explanations for the Neanderthal extinction. However, this doesn't mean their morphology didn't play a large role in their extinction. As I mentioned before, the Neanderthals were best adapted for colder climates. So while Neanderthal morphology didn't lead to the creation of vast symbolic and cultural practices, it did most likely play a leading role in their extinction as the climate changed rapidly. So for next time: climate change and environment. How did it affect the both species?
Morphological Features of Homo Sapiens (Anatomically Modern Humans):
Cranial Features:
- Average Cranial Capactiy: ≈1300 cc
- Lack a bipartite brow with a more bulging medial portion.
- Conchal crest that marks the anterior articulation of the inferior nasal concha.
- A parabolic palate.
- A prominent mental eminence.
- Short base and high brain case.
- Skull is broadest on top.
- Very little, if any, post-orbital constriction or narrowing behind the eye sockets.
- Short jaws, which result in an almost vertical face.
- Generally, orthognathic.
- Mandible has a protruding, bony chin (Homo sapiens are the only early hominid with this feature).
- Due to the shortened jaw, the parabolic shape of the palate causes the side rows of teeth splay outwards rather than remain parallel, as in our earliest long jawed ancestors.
- Teeth are much smaller than in Neanderthals. It is especially noticeable in the front incisors and canines.
- In the lower jaw, the first premolar teeth have two cusps of equal size.
- Face is reasonably small.
- Brow ridge is limited, and the forehead is tall.
- Back of the skull is rounded, which indicates a reduction in neck muscles.
- Lower, squarer eye orbits.
- Presence of a canine fossa (hollowed cheeks).
- Flatter, more angled cheek bones.
- Longer curved of the parietal and occipital bones.
- No retro-molar gap behind the third premolar.
- More prominent mastoid process (especially in males).
Source: Dorey, F. (January 4th, 2011). Homo sapiens- modern humans. Australian Museum. Retrieved on November 12th, 2012, from http://australianmuseum.net.au/Homo-sapiens-modern-humans/
Example of these features . . .
 | |
| This skull, named Skhul 5, was found in Skhul Cave at Mount Carmel, Israel. Although the Skhul 5 skull has more robust brow ridges, as seen in Neanderthals and earlier Homo ancestors, it also has a rounded brain case, a high vertical forehead, and lacks a projecting occipital bun (which is present in many Neanderthal remains). |
Source: Smithsonian Institution. What does it mean to be human?. Retrieved November 12th, 2012, from http://humanorigins.si.edu/evidence/human-fossils/fossils/skh%25C5%25ABl-v
- Long limb bones are thinner, and less robust. This indicates reduced musculature compared to Neanderthals.
- Smaller shaft proportions relative to limb length.
- Smaller measures of articular limb length relative to limb proportions.
- The femora lack midshaft flattening and excess internal thickening of the cortical bone.
- metacarpals and metatarsals (finger and toe bones) are straight, and don't have a curvature.
- Pelvis is narrower from side-to-side.
- Pelvis has a deeper 'bowl' shape from front-to-back.
- Early male Homo sapiens had an average height of 175cm, and females had and average height of 160 cm.
- Slender trunks and long limbs.
Source: Dorey, F. (January 4th, 2011). Homo sapiens- modern humans. Australian Museum. Retrieved on November 12th, 2012, from http://australianmuseum.net.au/Homo-sapiens-modern-humans/
This video is an EXCELLENT source for understanding the differences between modern and archaic human skulls.
Morphological Features of Neanderthals:
Cranial Features:
- Cranial capacity: ≈1300-1800 cc
- Suprainiac fossa (a groove above inion).
- Large, protruding occipital bun.
- Heavy mid-face prognathism.
- Less neotenized skull than Homo sapiens.
- Low, flat, elongated skull.
- A flat basicranium.
- Supraorbital torus (large brow ridge).
- Lack a protruding chin.
- Presence of a crest on the mastoid process behind the ear opening.
- No groove on canine teeth.
- A retromolar space posterior to the third molar.
- Bony projections on the sides of the nasal openings, and a projecting nose.
- Distinctive shape of the bony labyrinth.
- Larger mental foramen in the mandible for increased blood supply.
Source: Wikipedia. (November 8th, 2012). Neanderthal Anatomy. Wikipedia. Retrieved on November 11th, 2012, from http://en.wikipedia.org/wiki/Neanderthal_anatomy
Both of the images above show the differences between between cranial morphology in Neanderthals and Homo Sapiens.
Neanderthal Post-cranial Features:
- Considerably more robust in stature; stronger build.
- Long collar bones, wider shoulders.
- Barrel-shaped rib cage.
- Short, bowed shoulder blades.
- More laterally curved radius with a radial tuberosity placed more medially.
- Longer radial neck.
- More ovoid radially head.
- Well developed interosseous crest.
- The trochlear notch on the ulna faces more anteriorly.
- The brachialis insertion is lower, and the mid-shaft is larger and more sinusoidal.
- Larger round fingertips.
- Thick, bowed shaft of the thigh bones and femur.
- Short shinbones and calf bones.
- Longer torso.
- Proportionally shorter legs.
- Long superior pubic ramus.
Source: Wikipedia. (November 8th, 2012). Neanderthal Anatomy. Wikipedia. Retrieved on November 11th, 2012, from http://en.wikipedia.org/wiki/Neanderthal_anatomy
Again, the video above does an excellent job explaining the intricacies of Neanderthal and Homo sapien morphology and evolution.
The short video above shows how scientists recreate a Neanderthal man from skeletal remains.
Now for the fun stuff. . .
Everything I just mentioned is, in the grand scheme of things, simple facts that only help us understand the complexities of early hominid existence. What I am truly interested in is how these morphological features played into the development of symbolic practices, such as hunting and burial practices. More importantly, did any of these morphological features have an impact on the Neanderthal extinction?
It is commonly known that Neanderthals are very well adapted for cold climates, which is also in accordance with Bergmann's and Allen's rules. They had wider noses to heat the cold air before it enters their lungs, and their heavy brow ridges protect their eyes from the sun. So, in terms of hunting practices that developed out of these skeletal traits, we often see the pattern of injuries among Neanderthals resemble those of rodeo performers, which suggests that they hunted with weapons that required them to get close to very large animals. We know this from our previous discussion of lithics.
Since some Neanderthals apparently lived a long time after serious injuries, such as tooth loss, partial paralysis, and severe broken bones, it has been suggested that Neanderthals potentially took care of the sick, injured, and old. For example, at La Chapelle-aux-Saints there was a specimen found that was and old male (roughly 45), with incapacitating arthritis of jaw, back, hip, and almost no teeth. There is also evidence of an old man being taking care of at the site of Shanidar. This old man had crushed eye orbits, and was most likely paralyzed. However, yet evidence of atrophy and healing showed on the bones, which tells us he was most likely cared for.
In Homo sapiens, there are many more instances of symbolic practices being used. This is potentially because cognitively modern Homo sapiens would have had more "old, experienced people around than did previous hominids. This might have increased their ability to accumulate experience and knowledge, and for younger individuals to learn from older ones, encouraging varied local cultures and more rapid cultural change." (Source: Owen College. (2008). Neanderthals and homo sapiens. Owen College. Retrieved on November 12th, 2012, from bruceowen.com)
The evidenced just discussed points out that there were obvious instances of lifestyle practices that developed out of the specific morphology of Neanderthals, but it doesn't really point to any good explanations for the Neanderthal extinction. However, this doesn't mean their morphology didn't play a large role in their extinction. As I mentioned before, the Neanderthals were best adapted for colder climates. So while Neanderthal morphology didn't lead to the creation of vast symbolic and cultural practices, it did most likely play a leading role in their extinction as the climate changed rapidly. So for next time: climate change and environment. How did it affect the both species?
Nice
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