Topic 5: Archaic Homo

Learning Objectives

• What are the major species of the genus Homo?

• Why is human evolution not a linear process?

• What are the adaptive strategies of Homo erectus?

Species within the Genus Homo and the Relationships among them

• Homo rudolfensis (H. rudolfensis)

• H. habilis

• H. erectus

• H. antecessor

• H. heidelbergensis

• Neanderthal

• H. floresiensis (the “hobbits”)

Evolution is not a linear process!

Archaic Homo—H. rudolfensis

is based on KNM-ER 1470 skull found in Kenya in 1972.

• The earliest representative of the genus homo

• Cranial capacity larger than that of Australopithecus (775 cc)

• Large molars, more like Australopithecus

Archaic Homo—H. habilis

The first fossil of H. habilis (OH7) was found in Tanzania in 1960

• Called “The handy man” because they possibly made the Oldowan pebble tools

• Cranial capacity: between 600 and 700 cc—clearly separating them from austrolopithecines.

• Controversies surrounding its relationship with H. rudolfensis

Archaic Homo—H. erectus

• Range in age between 1.9 million and 50,000 years ago (coexisting with H. Habilis) they avoided competition with each other

• A highly successful and widely dispersed species

• The most complete fossil find—the Turkana boy, found in 1984.

• if we understand H. erectus better then we will know H. sapiens (us) better.

H. erectus - Adaptive Strategies

1. The Development of Stone Tools

2. Making and Using Fire

3. Biological Changes

4. Was language an additional advantage?

The Development of Stone Tools

• Proliferation in the number and diversity of tools

• Acheulean toolmaking tradition associated with H. erectus

  • Oldowan Pebble Tools:

    Australopithecus or H. habilis

    (picture provided)

  • Acheulean toolmaking tradition

    H. erectus

    more sophisticated

    aided hunting and gathering

Making and Using Fire

• Protection

• Survive winter’s cold

  • now humans could move to colder regions and expand their regional range

• Cooking

  • less calories wasted trying to eat tough raw meat

  • killed bacteria

• Social life

  • helped each other survive

  • very distinctive characteristic of homo erectus

  • civilization began when we started to support each other (proof from healed thigh bone)

Part of how humans evolved

Biological Changes

• The shedding of body hair and the ability for long-distance running (animals that pant are faster but can’t run further distances)

• Even smaller teeth, jaws, and torsos (as a result of cooking), compared with earlier hominins

• Less prognathic faces (our faces are more vertical)

• Increased cranial capacity (Australopithecine—500 cc; H. erectus—1,000 cc), vertical forehead, and thicker skulls

Was language an additional advantage? It is only a POSSIBILITY

• Cooperative hunting and making sophisticated tools may require or stimulate language

• Possibility of rudimentary speech among H. erectus.

• The adaptation of H. erectus is facilitated by culture/biology synergy

Expansion of H. erectus

• East and West Turkana, Kenya, dated 1.6 m.y.a.

• Upper Bed II, Olduvai, Tanzania, dated 1 m.y.a.

• Trinil, Java, Indonesia, dated approximately 700,000 years ago

• Zhoukoudian, China (a.k.a. “Peking Man”), dated 670,000–410,000 years ago

• A probable H. erectus cranial fragment found in Italy, dates to 800,000 m.y.a.

• The site of Dmanisi, in the former Soviet Republic of Georgia, has produced two skulls dated to 1.77–1.7 m.y.a.

Homo erectus needs meat rich diets to survive, but the earlier species, like Lucy, did not need as much meat to survive

Archaic Homo—H. antecessor

• Fossils entirely from caves in northern Spain

  • 6 individual skeletons found

  • their facial features started to resemble modern humans

• Possible common ancestor of H. heidelbergensis

First migratory wing from Africa

Archaic Homo—H. heidelbergensis

• Fossils found in Heidelberg, Germany

• Share features with H. erectus and H. sapiens

• Cranial capacity: 1250 cc (close to what we have now)

• It may gave rise the Neanderthals (could be a direct ancestor to Neandrethals)

Archaic Homo—Neanderthals

• First discovered in 1856 in a German valley called Neander Valley

  • When scientists first found this they were very confused, it looked so similar yet so different from modern humans

• Very large cranial capacity (1,450 cc)

  • larger brain than modern humans

• Rugged appearance

• This particular man suffered from arthritis, but scientists back in the day thought that the neandrethals just had difficultly walking as a whole. (No they didn’t)

Cold-Adapted Neanderthals

• An important environmental change faced by the Neanderthals is ice ages (glacial).

• Cold-adapted traits: large torso, short limbs, broad nasal passages

• Average of 50 degrees C colder back than than today

• Human brains don’t do well with sudden cold changes in temperatures, there is less oxygen which is not good for the brain, so that is where large noses come from.

Neanderthal tools

• Oldowan Tools: Australopithecines or H. Habilis

• Acheulean toolmaking tradition: H. erectus

• Mousterian toolmaking tradition: Neanderthals, who revolutionized the technique to make flake-tools

• We can identify 14 different kinds of tools used for different purposes

The Relationship between Neanderthals and Modern Humans

The prevailing view: H. erectus split into many separate groups, one group was ancestral to Neanderthals, and another one ancestral to Anatomically Modern Humans (AMH)

• Question debated by anthropologists for a long time: Why did Neandrethals die off/disappear

• About 60,000 years ago, humans moved Neandreaths to extinction (SEPARATE SPECIES)

• After homo sapiens moved to Europe, ancestry of neandreathas still live in DNA of asians

H. floresiensis (the “hobbits”)

Caves on Flores Island, Indonesia, where the specimens were found in 2004. 

Very mysterious species, they stood 3 feet tall, with a brain much smaller (about the size of a chimpanzee). Initially thought this species suffered from a disease causing their dawrfism and small brain, but this proved to be incorrect. Despite their brain size, they could make fire and had even more sophisticated tools than the other homo species, they also had sophisticated culture, all of which puzzles anthropologists. 

How does the discovery of H. floresiensis challenge conventional thoughts about human evolution?

• Could adaption change the general evolutionary trend? (the general trend was that animals would get bigger in evolution instead of smaller, but in some particular species some got smaller)

• Is cultural development directly related with the brain size?