Homo erectus

Homo erectus means ‘upright man’.  In the scientific classification system species are commonly identified by two names (binomial nomenclature). The first name is the genus and the second is the species (the first word is always capitalized, the second is not) hence; Homo erectus.  The time period for Homo erectus is 1.9 million years BCE (before the common era) to 70,000 years ago.

Homo erectus skull front view

The First Homo erectus Discoveries 

Charles Darwin published his landmark book ‘On The Origin Of Species’ in 1859.  In the book he presented his compelling evidence for how all species evolve through time.  There was a lot of resistance to this theory at first, especially when it came to humans.  And in fact there are still large groups of people that (mostly based on their religious beliefs) reject Darwin’s hypothesis. 

Now at the time of Darwin the actual fossil evidence for human evolution was basically nonexistent.  There were a few pieces of Neanderthal skeletal remains that had been found in Europe more or less accidentally but that was about it. 

'Java Man' is the first Homo erectus found.

Eugene Dubois was a Dutch anatomist and in 1886 he went to Asia on the first expedition solely focused and organized to search for the ‘Missing Link’ between man and ape.  He went to Asia because at the time Asia was considered to be the cradle of human evolution.  Dubois was rewarded in 1891 when his team discovered what ended up being called ‘Java’ man, the first Homo erectus found.  

The next big Homo erectus find was Peking man found in China by Johan Gunnar Andersson in 1921.  He uncovered 200 erectus fossil fragments from more than 40 individuals including five nearly complete skullcaps.

One of the 'Peking Man' skull caps.

Dubois’s find was prior to Raymond Dart’s African discovery in 1924 of the species he named Australopithecus africanus.  Australopithecines are now considered the first early man and established Africa as the birth place of mankind.

It wasn’t until the 1950’s that African discoveries of Homo erectus cemented what by then most had already assumed due to the Raymond Dart discovery that Africa is the cradle of humanity.  This view was further validated by a fossil discovery in 2013 of a jawbone dated 2.8 million years ago which seems to be a link between Australopithecus and Homo erectus.

The Fossil Evidence

Since the year 2000 there have been several new fossil finds and several new interpretations of what and who Homo erectus was based on those finds.  The more hominin fossil evidence that is unearthed with any species the clearer the picture becomes about them.  However, even given the same fossil evidence and data, different opinions can and are developed.  The other thing to keep in mind is that the total fossil remains that have been unearthed is still scant.  We are talking about dozens of individuals not thousands.

Here is a great example of the amount of skeletal remains at a dig site. The AsianScientist publication reported on November of 2015 of a new major Homo erectus find in China . They called it an important site for Homo erectus and indeed it is.  Here are the skeletal remains unearthed there.

 

I don't think anybody would call it the 'Mother Lode' but in fact there was quite a bit of material discovered as these things go. 

Here is another major Homo erectus Chinese find from 1964.  These remains where found in a small village and dated to one million years ago.

Now I would like to show you some astoundingly complete and well preserved Homo erectus skulls.  The first one was found in Java in 1969.  The second was found in Kenya.

 

As you might imagine a time period of a million years or more imposes a tremendous variety of environmental influences on any bone material. Ground pressure, erosion, soil make-up, all of these things and more contribute to the decompositional forces upon skeletal remains.

To me it is amazing scientists can find any hominin remains at all but they do and continue to do so.

Hominin fossil remains unearthed are just fragments of bones, partial pieces of jaw, teeth or skull cap or some other bone.  The picture of human evolution we have now has been developed by paleoanthropologists analyzing what amounts to nothing more than meager amounts of fossil material unearthed. However, with expert analytical skills and the collective body of skeletal remains, scientists have given us a very good idea of what our ancestors looked like and where capable of.

 The most complete Early Human Skeleton ever discovered.

Of course there are always exceptions aren't there.  The exception is the Nariokotome Boy found in 1984 by Richard Leaky (son of the legendary archaeologists Louis and Mary Leaky) in Nariokotome, Kenya.  The boy is presumed to have been about 10 years old and lived 1.6 million BCE. Except for the skull the boy looks very much like a modern human and it is believed he would have grown to 6'1" tall (1.86m).

This is what Leaky had to say in 1988.

And here he is, the Nariokotome Boy. 

Pass Me The Data Please

If we had thousands of complete skeletons from each early man species there would not be all that much room for diverse opinions about the evidence. But from the evidence we do have different interpretations arise that can be and are expounded upon.

As an example of how the same data can lead to different interpretations it now appears that during the early time period of Homo erectus there was only one Homo erectus species where a few years ago it was presumed there were several closely related species. 

In 2013 the documentation of the Dmanisi skulls (discovered in Dmanisi, Georgia) highlights the overall situation of paleoanthropology’s shifting view of human evolution and its dependency on the limited fossil evidence. 

Previous to the Dmanisi skulls it was assumed that there were a few different species of Homo erectus such as Homo rudolfensis and Homo habilis.  

This photo is of skull 5 from the Dmanisi skulls. Skull 5 is the first completely preserved adult hominin skull from 1.8 million years ago in the Lower Paleolithic.

The Dmanisi skulls (there are only 5 of them) are Homo erectus skulls but they have a large variation between them.  After careful study of the Dmanisi skulls views about there being separate Homo erectus species have changed and now at best there are subspecies considered or just variations on a single evolving species of erectus. The brain size for Homo erectus has been measured between 850 cc and 1100 cc.

In fact the variations so far found with the Homo erectus skulls are no more than found in the skull variations of modern Homo sapiens.

Let’s consider this, Homo erectus was around for a long time. Homo erectus skeletal remains have been unearthed throughout the ‘Old World’.  There are sites in Africa, Europe, Eurasia, and all of Asia. The oldest erectus fossils date to about 1.9 million years ago and the most recent fossils from about 70,000 years ago.  That’s a really long time and it makes sense there would be big variations in the fossil evidence over such a long time period.

Homo erectus represented a quantum jump in human evolution.

Let me list a few of the major advances Homo erectus made for human evolution.

  1. They made and produced sophisticated tools.
  • stone axes
  • sharp stone cleavers
  • sharp stone knives
  • wooden spears
  • wooden bowls
  • long fine spear points
  • big choppers
  • skillfully crafted tools from obsidian
  • tools with double sharp edges
  • wood tools
  • tools made with bone, antler and fangs

Stone tools by H. erectus

Acheulan tools is the name given to a tool set of stone hand axes used by Homo erectus for over a million years.

       2. They hunted in groups
       3. They hunted large prey like elephants, rinos, etc.
       4. They tamed and used fire to cook meat, tubers and roots
       5. They made stone hearths and clay ovens
       6. They made the first houses
       7. And let's have a drum roll please, the big one...

Language!

Language was undoubtedly developed to a fairly high degree.   Home erectus must have used language to be able to hunt in groups and make houses and achieve all the other things they did. It stands to reason that to pass along their cumulative knowledge they required the ability for abstract reasoning and for the use of symbolism and for that they needed to able to talk in clear terms.   

We have no idea exactly how advanced the language of the Homo erectus was but we know that complex hunting and gathering strategies involve conceptualizing and communicating about time.  This ability gave our ancestors a huge survival advantage. 

You can't grunt your way to greatness.

It is well established that erectus built houses by using limbs as a framework and stretching animal skins over that.  In one such structure excavated a mammoth tusk was presumed to have been used as a center pole.  One structure was 50 feet long.  You don't build structures like that with just grunting noises.  It takes coordination and planing plus being able to give and take directions.

There is a very long and complicated discussion about the physical structure of the head, ear bones, neck and spine that scientists talk about when speculating if Homo erectus had language or not. My position is look at the way they lived and what they accomplished.  Can you do that by grunting? 

Hand it to Homo erectus 

The bone structure of the hand is vital for tool use. The bone structure of Homo erectus has allowed the human lineage to develop one of the major milestones in our evolution which is the making and using of complex tools.

In order to make and use complex tools it is critical that the hands have the dexterity and strength to get the job done.  In H. erectus we first see what is called a “styloid process” which is a small projection on the third metacarpal in the palm of the hand. This small adaptation in the hand has made all the difference in the world to human evolution, it has given us the hands we have today.

The third metacarpal bone connects to the middle finger, and the styloid process on it connects to the wrist and makes grasping objects easier. 

Other non-human primates do not this styloid process.

Let’s take a look at this seemingly inconsequential physiological feature of the third metacarpal.  You can clearly see in the next photo, as indicated by the arrows, the styloid process on the human metacarpal and the H. erectus metacarpal found in Kaitio, Kenya.

Now let’s look at where the bone is in relation to the whole hand.  This feature allows for a much more powerful grip and increased dexterity.  Both of which are crucial in making and using complex tools.

Running, Running, Running

Because Homo erectus had basically the same skeletal structure as modern humans he could run!  Running upright is huge.  Consider this, erectus could run flat out with a spear in its hand or some other weapon or tool.

 Striking Death at a Distance

Using spears gave erectus a major, major survival  advantage. Other predatory animals have to physically come in contact with prey by clasping them either in their jaws or claws.  But with the ability to throw a lethal spear some distance, erectus could not only expand the kill zone to dozens of feet for itself but also drive off predators before they even came in contact with him. 

How good where the spears?  Spears found at H. erectus sites are the same length and balance as modern javelins.  

More Homos than you can count on one hand.

Interestingly enough Homo erectus gave rise to several other Homo species. 

And in fact around 300,000 years BCE there were seven known Homo species alive and in all probability there was a lot interaction between them even interbreeding. 

First you had Homo naledi and Homo erectus, there is evidence that Homo heidelbergensis was still alive, then Homo neanderthalensis, Homo denisova, Homo floresiensis and of course Homo sapiens. 

Homo denisova bone fragments were first discovered in 2008, Homo floresiensis was first discovered in 2003 and in 2013 Homo naledi was discovered.  There may still be more Homo species discoveries to be unearthed.  To me the relationships between the different Homo species is a fascinating story yet to be fully understood.  However, one point all paleoanthropologists can agree on is Homo erectus is in the Homo genus and the direct ancestor of us all. 

  1. Kingdom – Animalia
    2. Phylum – Chordata
    3. Class – Mammalia
    4. Order - Primates
    5. Family – Hominidae
    6. Genus – Homo
    7. Species – erectus

 Some Closing Thoughts

Anthropologists agree that H. erectus lived in a hunter-gatherer type of society.  They most likely cared for the weak and elderly and hunted in coordinated hunting parties.  They are the first artists also.  Shell engravings found have been dated to 540,000 years ago.

Here is a reconstruction of Home erectus built from the skull up.

I am not saying that if you saw a H. erectus in modern clothes walking down the street it wouldn’t make you wonder but then again it wouldn’t make you aghast either.  The upright gait would not cause any alarms and the body proportions would pass muster it’s just that a close look at the head and face might be a little disconcerting.

Homo erectus skull side view