Top 10 discoveries in archaeology in 2006

 

In its final 2006 issue Archaeology Magazine  listed the top 10 discoveries in archaeology made this year. Here are my favorites:

The discovery of a three million year old child in what is now Ethiopia.

I wrote about Baby Selam in another contribution.  Her discovery adds to a growing collection of fossilized remains. Occasionally you might find a reference in the literature minimizing the finds. Usually this is done in terms of the volume represented by these bones. Some authors think that the total volume of fossilized hominid remains might easily fit in a box, or a pick up. Aside from being wrong, this is totally irrelevant. Researchers continue to unearth more fossils every year. This not only adds to the volume of known bones, it also improves our understanding of human evolution. That is what is most important.

Pushing back the dates on the development of writing in the New World.

All too often people focus on the development of writing in the Old World. Researchers quite frequently fall into the trap of looking for the absolute earliest evidence of a certain achievement. By doing so, they fall into the trap that the earliest writing system was at the root of all other writing systems. Not so. The indigenous cultures of the Americas stand out in many ways, not in the least because of the fact that their civilizations made remarkable progress independently from the Old World. Diffusionists notwithstanding, the Olmec, Maya, Aztec and Inca people were capable of great things, which they learned on their own.
A discovery of a carved stone in the southern part of the Mexican state of Veracruz has pushed back the date of the earliest writing in the Americas . Originally estimated to date to about 2650 years ago, writing now seems to have been around 3000 years ago .

DNA analysis identifies human remains found near the tomb of China’s first Emperor to belong to a man from Persia.

A popular line in many of Hollywood’s movies is “You can run, but you can’t hide.”  It seems that some of that message is now rubbing off onto the archaeology world. Take the case of human remains found in the proximity of the tomb of China’s first emperor . At a distance of about a half a kilometer from the museum housing the world famous terracotta warriors, Chinese archaeologists uncovered a mass grave containing the remains of at least 121 individuals. Genetic testing was performed on 15 people. Much to the delight of the scientists, the DNA of one of these men pointed to a west Eurasian origin, possibly Persia, or what is now roughly Iran.  All kinds of speculation abound about who this man might have been and what he was doing in China. Professor Victor Mair of the Center for East Asian Studies at the University of Pennsylvania  is very intrigued by the find but has already cautioned that this only conforms what we already knew: there was an influx of foreigners into early Imperial China.

Not on the list, but worthy of an honorable mention, at least in my book, would be the following breakthroughs.

A better understanding of the Antikythera mechanism.

In 1900 sponge divers off the coast off the island of Antikythera , in the Aegean, encountered a shipwreck littered with artwork and one mysterious item. The device, which was heavily corroded, consisted of a several interlocking wheels. What was it? A time device?  A computer?  Not until recently did we finally find out.

Researchers from the University of Cardiff, Wales, studied the mechanism using cutting edge scanning technology. They were able to read the inscriptions on the device as relating to the motions of the moon and the sun . They established the date of the mechanism at 150-100 B.C.

This is a unique device, the likes of which were not seen again until about 1000 years later. One is left wondering what led to the disappearance of this knowledge. What might have been if such a loss had not occurred? We will never know.

Worth keeping track of: possible discovery of Aztec emperor’s tomb.

Anyone digging a pit in downtown Mexico City is bound to come across remnants from Aztec times. And so it was late 2006, when the following story hit the wires “Tomb of Aztec Emperor May Lie in Mexico” .  A large carved stone slab, said to represent the goddess Tlaltecuhtli  was uncovered in the Mexican capital. A date encountered on the stone places it during the reign of Emperor Ahuizotl . The size of the stone, as well its representation of a fearsome deity, have led archaeologist Eduardo Matos  to surmise that it could be a grave marker for the emperor. Excavations are ongoing at the time of writing.
If the prediction holds true, this would be the first imperial grave ever found in Mexico.

Lucy’s Kitties

Lucy’s World:

Big Cats Everywhere:
Fast Cats, Climbing Cats, Saber-Cats, Semi-Saber Cats, even Fast Saber Cats.

I love Lucy. Anatomically, that is. Her skeleton is a marvelous combo. She has our human joints – knee, ankle, wrist, backbone – for upright posture. And she has some chimp/gorilla-style components – short legs, slightly splayed big toe, long forearm, upper arms that could swing high above her head, and small brain. Plus some unique features we don’t see in any modern species – the ball on the thigh bone is set on a long neck that comes off the main shaft.

Modern australopith specialists seem to agree that Lucy was a triple-threat. She could run as we do, bipedal, on flat level ground. Short legs meant that she wasn’t super speedy. She could swim, with kicks and arm swings. And she could climb far better than we, since her shoulder was more ape-like, her big toe was a bit divergent and her shin was shorter.

Lucy and her kind needed three-dimensions to move because she was surrounded by a spectacular array of predators, all of whom loved Lucy in a culinary sense. The australopith age (5.8 to 1.8 million years ago) produced the richest and scariest variety of big feline meat-eaters the world has ever seen:

1) Leopards. Modern-style leopards were common in forested habitats. Just like their modern day survivors, the fossil leopards have short, wide, flexible legs and body, a build excellent for sudden ambush, great leaps, and agile climbing. Body weights went from 50 lbs to 200 lbs.

2) Lions & Tigers.  The lion-like cats are rare but present with australopiths at a few sites. Lion-like cats are huge, up to 500 lbs, with a build designed for open-habitat hunting in groups. Legs are longer, straighter than a leopard’s. Speed over level ground is higher. Because of the great weight, climbing is less agile.

3) Cheetahs. Turbo-cats – these speedsters have greyhound-like limbs, very long and tipped with nails not claws. Living cheetahs are leopard size – 120 lbs average. But fossil cheetahs got as big as lions and are  common in australopith sites all over Africa. Cheetahs sacrifice climbing ability for acceleration and velocity on the ground.

4) Semi-Saber Tooths – Dinofelis. These felids have the bodies of leopards with an enlarged upper fang. The saber isn’t as long and sharp as a true saber tooth’s but is far more formidable than in any modern cat.

5) Dagger-Tooth Saber Cats – Homotheres. The faster of the two kinds of true saber-tooths, homotheres grew to lion size but had longer forearms and often longer paws, with nail-style claws. Climbing would be slow but speed on the ground higher than a lion’s. The jaws are frightening – the mouth could open very wide, baring huge upper teeth shaped like daggers. The tooth crown was flat side to side, wide front-to-back, and exceptionally sharp front and rear.  Like a meat-eating dinosaur fang, the homothere killing tooth was saw-edged.

6) Sword-Tooth Saber Cats – Smilodonts.  Shorter in the limb with more jaguar-like paws, the smilodonts were, on average, far slower than their homothere cousins but much better at climbing. Sizes ranged from leopard to tiger, 50 lbs to 500 lbs. The killing fangs were longer but thicker and stronger – better for stabbing deeply.

Ok – imagine that you are Lucy, 3.4 million years ago. Can you outrun any of these five cat varieties? Nope. Even the thickest-limbed leopard or smilodont could catch you in a hundred yards. The cheetahs and homotheres would get to you even more quickly. What do you do? Go up. Leopards and Dinofelis and small smilodonts could climb well, so you better go even higher in the trees, holding on to branches too thin for the cats.

Remember – australopiths didn’t make stone tools. Their best defense would be to escape to a cat-free micro-environment. The threat from cats probably explains the combination of design features we see in australopiths – with an emphasis on superior climbing ability. The ape-like shoulder was a key joint – it let Lucy grasp small branches above her head as her toes held on to a lower branch.

Texas Connection. And yes, the Lone Star State had every one of the five types of big cats.  The Bering Land Bridge let new cat species spread from Old World to New World and vice versa as soon as they evolved.

How do we know: dating techniques

It is fairly easy for all of us to grasp events that happened a generation or two ago. Quite often, we heard stories from our parents and grandparents relating to these. Most people don’t have problems either with things that occurred centuries earlier.  We know Napoleon existed, and so did Julius Caesar.  Babylon was a reality as well,  but as we keep going further back in time, questions arise. How do we know that Lucy lived 3.12 million years ago? 

The approaches used in dating the fossil remains of early humans vary from region to region. In Africa, there are regions where we can use volcanic ash to help date the layers in which, or between which early human fossils have been found. This technique, known as paleomagnetic dating, has been used in East Africa, including on the site where Lucy was found. Volcanic ash layers, unfortunately, are not available in Southern Africa. Here another technique has been used, known by its fancy name as biostratigraphy.

Biostratigraphy, or the dating of layers of rocks and dirt based on the presence of animal fossils, relies on the known and dated presence of specific animal species. If animal remains are found in association with human remains, then one can compare the animal remains against those found elsewhere, specifically those found in areas where other dating techniques are available. Scientists prefer working with animal species that had a great geographic range and with short lived history. (The latter is important so that the period of time during which they could be incorporated in the sediment is relatively narrow and therefore easier to date.)

These approaches reflect flexibility on the part of scientists.  You may be aware of a technique that would help you date a fossil, but if you do not have the right material (like volcanic ash) to work with, then you have to resort to other approaches, such as biostratigraphy.

A dating technique that is very well known is radiocarbon or C14 dating.  This does not apply here.  Radiocarbon dating can only help us go back in time 50,000 years ago, give or take a few thousand years. Since Lucy lived well before that, radiocarbon is of no use to us in this case.

Paleoanthropology: making the past come alive.

Here are some questions you might have: Lucy and her relatives lived millions of years ago.  How do you find out what Lucy looked like? How do you know what she ate?  What was the environment like when she lived? Who can answer these questions?

Paleoanthropologists.

Paleoanthropologists, or people who study early humans, specialize in finding answers to these questions.  Working with scientists in other fields, these scholars act like detectives, although the trail they follow is truly cold. They tease information from the material remains of a distant past, sometimes millions of years old. This is not an easy job, but it is a fascinating one.

As a paleoanthropologist, you will spend a lot of your time outdoors.  However, before you do, you need to develop your research plan. Imagine that you are interested in who walked around on our planet 4 million years ago. You will need to be able to locate those areas on our planet where you can easily access 4 million-year old geologic layers. Geologists can help you to find these layers. At that point, you and your team will go to work. Your training, as well as patience and luck will contribute to your success.

You will be looking for bone fragments that are visible on the surface. This is the most practical approach to finding early human and animal bones. Since these early people did not leave any buildings behind, you only have their bones on the surface to go by.  Random digging into the ground to find early humans would waste your time and money.

If you are lucky enough to have found bone fragments, you will want to know what they are and exactly how old they are. Geologists and physicists can help with the dating of the soil in which the bones were laying. Your own training and that of animal specialists will help identify what or who you have found.

If you are extremely lucky, you may have found enough fragments to reconstruct parts of a skull or even parts of a skeleton, like that of Lucy. Using casts of these bones, skilled artists can then layer in the various muscles and slowly reconstruct the face.  

Dietary clues may be found in the teeth.  Some early humans have massive jaws with huge teeth covered by thick layers of enamel, capable of cracking the toughest nuts. Compare that to our jaws and small teeth and consider what we eat. 

Using clues like plant pollen and soil typology, other specialists can help reconstruct what the environment looked like when the early humans you found were around.

What emerges from this research, which can take an entire lifetime, is a snapshot of a distant past. It presents the best possible approximation of what these early creatures may have looked like, what they may have eaten and what the landscape looked like when they walked around. In other words, you have found some answers to your questions.