Anthropology Discussion 5

Lecture #18—Homo heidelbergensis and Homo

neanderthalensis

Tail End of Human Evolution

A Different View

Who Were Premodern Humans?

• Often used as a catch-all term for species post-Homo erectus but pre-Homo sapiens.

– Includes at least 3 distinct species:

• Homo heidelbergensis

• Homo neanderthalensis

• Denisovans—we will get to them next time

• These folks lived throughout Afro-Eurasia

– Homo heidelbergensis—Africa, Europe, Central Asia, East Asia

– Homo neanderthalensis—Europe, Western Asia

The Pleistocene

• Remember the Pleistocene from last lecture?

• The Last Great Ice Age

• Middle Pleistocene

– 780,000-125,000 ya

• Late Pleistocene

– 125,000-10,000 ya

The Pleistocene

Interglacial v. Glacial Periods in Africa

• Reduced rainfall during glactiations, increased rainfall during interglacials

• Affecting resource availability

• During glaciations, the Sahara Desert expanded, changing migratory patterns

– Cutting off migratory routes to N. Africa and beyond

– Interrupts gene flow between African and non- African hominid populations

The Pleistocene

Interglacial v. Glacial Periods in Europe

• Glacial Cover in Europe

– Green parts are likely human occupation, arrows show likely migratory patterns

• Premodern humans replacing Homo erectus in many places

– Coexistence in some places, particularly Asia where Homo erectus persisted for longer than anywhere else

• More successful European occupation than ever before

Homo heidelbergensis 800,000-200,000 ya

Homo heidelbergensis

• Early specimens H. erectus-like

– Large face

– Brow ridge

– Low forehead

– Thick cranial bones

• Modern features

– Larger brains

– Rounder braincase

– Smaller occipital bone

Middle Pleistocene Trends in Biological Evolution

• Climatic fluctuations likely selecting for increased behavioral flexibility

– Increasing brain size

– Increasing sociality

– Increasing reliance on culture

• Discussed in Becoming Human films

African Homo heidelbergensis

Kabwe or Broken Hill, Zambia

125,000 to possibly 400,000 YA

Bodo, Ethopia

600,000ya

European Homo heidelbergensis

Sima de Los Huesos, Spain

600,000-350,000ya

European Homo heidelbergensis

Steinheim, Germany

250,000 – 350,000ya

Petralona, Greece

400,000 – 250,000ya

Asian Homo heidelbergensis

Dali, China

230,000 – 180,000ya Jinniushan, China

200,000ya

Homo heidelbergensis

• Most likely common ancestor to

– Homo Neanderthalensis in Europe

– Homo sapiens in Africa

• That is to say,

– Populations of H. heidelbergensis living in Europe/Near East evolved into H. neanderthalensis by ~250kya

– Populations of H. heidelbergensis living in Africa evolved into H. sapiens by ~200kya

Who were the Neanderthals?

• Neanderthals were a highly specialized late Pleistocene population of humans living in the Western Asia and Europe

– ~250,000 – 30,000ya

– “Classic” Neanderthal features evident in the fossil record by ~150kya

• The LCA of Neanderthals and modern Homo sapiens (us) was likely H. heidelbergensis ~600kya (from mtDNA comparisons)

Geographic Distribution of Neanderthals

Late Pleistocene 130,000-10,000 years ago

A Few Neanderthal Sites

• Spain: Atalpuerca, Sima de Los Huesos

• France: La Chapelle, La Ferrassie, St. Cesaire

• Germany: Neander Valley

• Croatia: Krapina

• Iraq: Shanidar

• Israel: Amud, Tabun, Kebara

• Uzbekistan: Teshik-Tash

Cranial Comparison with Moderns

• Cranial Capacity = 1200-1700cc (modern 1200-1600cc)

• Receding forehead

• Skull is long and narrow with a pronounced occipital bun v. AMH with domed brain case

• Well-developed browridge

• Thick cranial bones

• Large, jutting mid-face—enlarged maxilla

• Large nasal bones

• Swept-back cheekbones

• Weak or non-existent chin

Neanderthal Dentition

Retromolar Gap

Neanderthal Dentition

• Teeth positioned far forward in the jaws producing a gap behind the 3rd molar

• Molars and premolars not significantly larger

• Front teeth larger than those of modern H. sapiens.

• Some specimens show significant wear on incisors

– Shanidar, Iraq

Post-Cranial Comparison

• Barrel-shaped chest

– Large, wide rib cage

• Large joints, muscle attachments—very big, powerful muscles

• Wide pelvis

• Bowed femur

• Relatively short limbs

Bowed Femur

• Bowed Femur

– Extraordinary muscle strength

• Round cross-section

– no bony ridge on the back (pilaster) found in modern people

Neanderthal Pelvis

• Longer and thinner with a larger pelvic inlet (birth canal)

• Adaptation for a longer gestational period?

Skeleton from Kebara Cave, Israel

Neanderthal Body

Proportions

A short, stocky build with relatively short limbs in comparison to modern people.

Body Size and Proportions

• Interaction with Environment

– Bergman’s Rule

• Ratio of Body Mass to Surface Area of Skin – As mass increases, relative surface area decreases

• Greater mass is more adaptive in colder climates – Heat conservation

– Allen’s Rule

• Ration of Appendage Length to Surface Area of Skin – As appendage length increases, relative surface area increases

• Shorter limbs are more adaptive in colder climates – Heat conservation

Body Proportions as a Thermoregulatory Adaptation

• Ice Age Europe?

– Really Cold!

• Neanderthal Adaptations to Cold

– Body proportions

– Broad nasal cavity

– Overall robusticity

Premodern Neanderthal Cro-Magnon Inuit

Body Proportions as a Thermoregulatory Adaptation

• Ice Age Europe?

– Really Cold!

• Neanderthal Adaptations to Cold

– Body proportions

– Broad nasal cavity

– Overall robusticity

Premodern Neanderthal Cro-Magnon Inuit

Note: Please excuse the inexcusable misrepresentation of

skin color. The Inuit is accurate and the Neanderthal is

possibly accurate as Neanderthals had been adapting to

Northern latitudes for some time but the Cro-Magnon (H.

sapiens in France about 30kya) would have had dark skin

because they were very recent immigrants out of Africa and

the Premodern (probably Homo heidelbergensis) would just

as likely have had dark skin depending on the time and place

of that particular individual. This, in my opinion, represents

the Eurocentric bias and the insidious nature of unexamined

racism in our culture. Additionally, the fact that all of the

individuals represented are male reflects the insidious nature

of unexamined sexism. It is my hope that in the very near

future we will have better materials that represent humanity

more accurately, not automatically making all

representations of late humans white or light-skinned and not

representing only one half of the species, reinforcing the

notion that male is the standard human and female a

variation.

Energetic Costs of Being Neanderthal

• Thermoregulation

– Warming the body in the cold temperatures of the mid- to late Pleistocene

– Up to 4000 calories a day required during the warmer months

– Up to 7000 calories during the colder months

• Relied almost exclusively on animal products

– Accomplished hunters of big game

– Calorie and Nutrient Dense

Early theories concerning the Neanderthals

…a barbarous

and savage

race

Modern Interpretations of Neanderthals

Running into a Neanderthal...

Levallois Technique

• Prepared Core

• Thin flake

• Virtually continuous cutting edge

• Saves raw material

• Greater variety of tools made this way

Neanderthal Toolkit:

Mousterian Tools

Uses of Mousterian Tools

Neanderthals lived very vigorous,

dangerous lives. Many

Neanderthal fossils show evidence

of healed bone injuries. This

graph (left) compares the rate of

healed broken bones from

Neanderthal fossils to modern

rodeo riders. The image above

shows a Neanderthal rib bone that

shows evidence of having been

broken, then healed.

Faunal Evidence for Hunting Many sites show a predominance of large game. Techniques probably included drives, hurling spears or bolas, and setting snares and some scavenging

LEFT: Atrophied right arm from Shanidar Cave,

Iraq. Shows an individual who must have been taken

care of to survive for several years after the arm no

longer worked.

ABOVE: Evidence of deliberate burial at Shanidar

Neanderthal Mortuary Practices

• Some believe that burial was solely utilitarian; disposal of an unpleasant nuisance.

• Others see burials as ritualized activities with a well-developed symbolic content.

Neanderthal Clothing

Stone tools such as scrapers were no doubt used to prepare skins for use as clothing.

Lack of bone needles in Mousterian assemblages

Neanderthal Housing Molodova (Russia) contains evidence of a dwelling with 15 hearths, and the use of mammoth bones as construction materials.

Post molds at Combe

Grenal (France) suggest

fairly substantial

constructions.

Shanidar • Several types of flowers and red ochre appear to

have been included in one burial

• Rodent burrowing makes some people doubt this evidence.

Shanidar Cave Site in Northern Iraq

Neanderthal Music?

• 43,000-82,000yo Flute – Bear femur

• Some controversy

Neanderthal Jewelry

• Little evidence of body adornment

• Pigments to color skin?

• Lack of social integration?

Neanderthals and Language

Neanderthal skeleton from Kebara

Cave

Kebara Hyoid

What Happened to the Neanderthals?

• Ultimately, Neanderthals disappeared. Why?

– Climate Change

– Competition with Moderns

• Direct

• Indirect

– At least a few absorbed into modern populations

• Genetics?

• Stay tuned for more…