If you have been reading my blogs, you would know from an early entry what a paleoanthropologist is; but in case you are new, first of all, welcome, and secondly a paleoanthropologist is one that deals with extinct hominids. These include Homo habilis all the way back to Australopithecus afarensis. Take that information with what this blog is titled, I am sure you can guess what exactly the Olduvai Gorge is. In the following I will discuss the information about our ancestors we have obtained from excavations to the first and new hominid that used tools.
       First off, just where is the Olduvai Gorge? This gorge is located in the northern region of the country Tanzania, which is in Africa. I mention that it is in Africa because that plays a huge part in the findings there. The Olduvai Gorge was at first seen as something that geologists were interested in because of the fact it “is the product of both abrupt high-energy processes like volcanism and plate tectonics and the slower low-energy process of weathering and erosion operating together over millions of years. (olduvaiproject.org)” When all this was happening there were several layers of earth put down, again, over millions or years. It was not until the early 1900's when scientists began to look at these layers. The one that was doing his research there was named Hans Reck, a volcanologist from Germany. First he was there just for the earth, then he found bones from extinct animals, and what looked like those of a hominid. He would have gotten so much more if he was allowed to continue with his research, but sadly the first World War was upon him so he had to go back to his homeland. The bones they had found were placed in the Berlin Museum.
       It was not until 1931 when he would be going back, but this time with help from a man by the name of Louis Leakey. Once Leaky arrived in Olduvai he realized how much this gorge held for the study of early humans. With these two men excavating they made another huge step in the future of research. They took great care to document everything they would encounter as they dug. From tools to bones, these were described and placed in chronological order. It was not until 1935 when an archaeologist joined the excavations, Louis Leakey's wife, Mary. She is the one who directed the archaeological excavations. From 1931 to 1947 they were working on ways to establish a sequence of artifacts and remains that went back 2 million years. They had found many stone axes in sediment which told them that there were humans living in these parts as much as a million years ago. Although all this new information was exciting, the most exciting thing happened years later.
       The Leakey's had stayed in Africa (Louis Leakey was born in Africa), and in 1959 Mary Leakey made the most exciting discovery in the Olduvai gorge; a hominid skull. Before this discovery they would find fragment of bones, some that were in better condition that others, but when Mary found this hominid skull, it was, by far, their most exciting find. Mary named it Zinjanthropus, “Zinj” for short. Not long after, in 1960, Louis found another skull which he named H. erectus. Now there was a problem with this though. Earlier, in Asia, there was another specimine also called H. erectus. But these two skulls were very different. The one Leakey found has a brain case with thin walls while the one found in Asia has thick cranial bones. This reason is why many people at the time thought that Asia was the cradle of life, not Africa. This H. erectus is now placed, along with others found in East Africa under the specimeine Homo ergaster. Even though the Leakey's had made great steps in the history of humans, the most wonderful discovery was just around the corner for Louis Leakey.
       In 1940 Louis and Mary Leakey had a child by the name of Johnathan. This is important because their child made the most exciting find in November of 1960. Found mainly at the Olduvai Gorge were many hominid fossils, amoung this vast collection of fossils Johnathan found OH 7; at the time this new discovery was named “Johnny's Child.” We now know this discovery as Homo habilis. Reason for this name is because it was, and still is, thought that this species created the vast majority of the stone tools found in gorge. H. habilis is the first known tool user, 2.4 – 1.6 millions years ago. This knowledge is the cause of the bones that were found.
       The H. habilis' appearance is close to that of Australopithecus africanus, which was discovered in 1925, but the H. habilis had smaller face and teeth and no sagital crest. Because of these changes in bones, it had smaller chewing muscles, which meant there was more room for larger more complex brains. The Australopithecus had a 300-500 cm3 size skull, while the H. habilis had one a size of 510-755 cm3. In the gorge they are most likely responsible for 200 stone tools with elephant bones. Not only were they the first to make stone tools, they were the first to migrate extensively. They inhabited Africa, Asia (China, Indonesia, and India), then later, 800,000 years before present they were in Spain, France, Germany, Greece, and England.
       I know that the blog is title Olduvai Gorge, but it was the Leakey's and their discoveries that added to the fame of the Olduvai Gorge. Just 27 miles from the Olduvai Gorge Mary Leakey found the Laetoli Footprints. East Africa has been the host to many history changing discoveries. If we were still under the impression that our origins were in Asia, without the knowledge Africa has given us, from stone tools to the different hominids found, who knows what kind of minds we would still have. We would most likely still believe we evolved from chimpanzees or gorillas or in search for the "missing link." From the Homo habilis, to Homo erectus, all the way back to Lucy's kind, the Australopithecus afarensis, it is just so amazing how much we know about our evolutionary ancestors, but at the same time how much we do not yet know. I mentioned that were many stone tools found, but I already wrote a blog on stone tools; if you would like to read that one here is a link to it: http://anthropologicalconcepts.weebly.com/blog/-lithic-technology
       Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover. 

      Charles Darwin. At one time or another everyone has heard this name. When his name is heard people think of natural selection, and when they hear natural selection they think of Darwin. But how did he come up with this? In honour of his birthday, which was this past Thursday (2/12/1809), in the following blog I will discuss how he came to his findings, research, and why it was something dangerous to publish in the time he was living in.
       The grandson of Erasmus Darwin, Charles Darwin is thought by many that it was his grandfather who inspired him. Reason being is Erasmus had views about several species having one common ancestor; not only that but he also wrote letters about the environment playing a huge part in evolution. But even before he got his hands on his grandfathers letters he was already interested in natural history; he would collect shells, birds' eggs, and even rocks. As an adult he went to Edinburgh University to study medicine. This choice of study also played a huge part in the evolutionary interests. While at Edinburgh University he was exposed to the evolutionary theories of Lamarck (he “suggested a dynamic relationship between species and the environment such that if the external environment changed, an animal's activity patters would also change to accommodate the new circumstances”), and other theorists.
       Even though he was exposed to many views on evolution by several professors at Edinburgh University, he left because, quite simply, he hated medicine. Soon he went to Christ's College to study technology. That said, given his interests he was pretty much indifferent towards religion. While there he took up interests in botany and geology. Armed with the knowledge he had cultivated and wanting to learn more, when he graduated he boarded the HMS Beagle on December 17, 1831 at the age of 22. This 5 year voyage was the start of a huge life change for Darwin and all around change in science.
       When Darwin boarded the Beagle he was in the state of mind that species were fixed as one form, but as the Beagle sailed he began to have secret doubts. Although, when the Beagle reached the Galapagos (islands off the coast of Ecuador) those doubts were no longer doubts but fuel for research. Darwin could see that not only plants but the animals on these islands looked similar but they were different from those of South America. Not only that but from island to island, or even on the same island some animals looked alike, but, again, were different.
       The title of this blog has “the legend” in it, and that is true. The study that Darwin did on the finches from both the Galapagos and from the mainland is nothing less than legendary. He found that several finches had notable beak differences. As he observed them he saw how the beaks reflected on how they obtained good. The ones with long straight beaks had to go into bark to get food, but other with small, thick, and short beaks would find food that was in plain sight.
       Once he arrived back in England he was writing papers on fossils to different plants, but the love for the change in species he had seen on his voyage on the Beagle over came him. This is when he began to develop his thoughts on natural selection. What this meant is that traits that are desirable are passed on but those that are not died off. In 1844 Darwin had written this thoughts about natural selection but he did not have enough research done to support it, so he did more. Another reason he did not publish his article is because the theory of evolution was seen as a threat to the church, and back then the church controlled everything. But 19 years later in December of 1859 he published “On the Origin of the Species.” Once this book was published there was a roar of disapproval about it (even nowadays the storm still has not abated). Even though the public, and most of all the church, saw the book with many negative emotions, the scientific community was in support of Darwin and his book.
       It is amazing how much one man who lived more than two hundred years ago had, has, such an impact on the scientific communities. His book has inspired hundred of thousands curious minds to see what they can find using him as the start; extending on his research. Darwin was the first to find out and realize that natural selection happens on genetic and individual level, while as a population, as a whole they change, they evolve. “On the Origin of the Species,” was just one of more than 20 published works Darwin put out there. The following is a quote from one of them named “The Descent of Man” which covers the evolution of man and sexual selection (sexual selection is similar to natural selection; traits that are desirable will be more likely to live on).
       “In each region of the world the living mammals are closely related to the extinct species of the same region. It is, therefore, probable that Africa was formally inhibited my extinct apes closely allied to the gorilla and chimpanzee, as as these two species are no man's nearest allies, it is somewhat more probably that our early progenitors lived on the African continent than elsewhere.” This is an example of how ahead of his time Darwin was. He has never been to excavations or the such, but he knew what we have just started to realize and accept. Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover.
       Happy birthday, Charles Darwin, the man, the legend.

       Evolution; this word has so much to do in our everyday lives without us giving it a second though. We have lived through an entire evolutionary process. This process is the one of the evolution of technology. Not even 30 years ago were cells phones, even personal computers seen as possible in our lifetimes. Nowadays some of us cannot leave the house without a piece of technology with us; whether it be an ipad, an iphone, or even a laptop. But has this evolution in technology hindered our own biological one? In the following blog I will address possible features of future humans and the evolution we have gone through as Homo sapiens.
       You must be thinking how could we have gone through an evolution as Homo sapiens but we are still Homo sapiens. One answer is we still have left overs from early on when we just became H. sapiens. One of these left overs is the appendix, although there is much difference in opinion whether or not it is useful. In the early days of the H. sapien the appendix was to help to extract nutrients from plants and uncooked foods we were to eat, along with helping to filter out dangerous bacteria. Since we have learned to clean what we eat along with cook what we eat, many believe that this organ is just around to get infected. Taking that into account, there are some who have studied the appendix at length to find out what it does now. It so happens that this vestigial organ is seen as vital towards fetus and young adults. Professor Loren G. Martin of Oklahoma State University states “endocrine cells appear in the appendix of the human fetus at around the 11th week of development. These endocrine cells of the fetal appendix have been shown to produce various biogenic amines and peptide hormones, compounds that assist with various biological control (homeostatic) mechanisms.” After the fetal and young adult state, in full grown adults the appendix helps in the immune functions. Although, that said, the appendix does not exist in domesticated animals. So why do humans, the being that has domesticated these animals, still have that ancient organ? But there is another body part that is painful for some when it comes along: the wisdom teeth.
       Unlike the appendix in which forms when all humans are in the womb, the wisdom teeth is a totally different process. Let us start with why we need, or better yet, still have wisdom teeth. Just like the appendix, we used our wisdom teeth to better break up plant life and uncooked meats. I theorize that before the advent of fire, all H. sapiens would get their wisdom teeth in before we do now. But as we began to not needing them as much, the rate of the growth of these molars was pushed further and further back til we reached late teens early twenties. The reason I am saying is because several current modern H. sapiens some of those teeth do not come out all the way, and with some the wisdom teeth do not even to erupt. Also, just like the appendix, a majority of the population who do get their wisdom teeth, the tooth gets infected and must be taken out.
       The last form of evolution we have gone through as the same species, is the most noticeable: skin colour. Now skin colour is not only evidence of evolution within our own species, but also of natural selection. What I mean by this is as we moved to different areas of the Earth, we were exposed to many UV rays, or not enough. The areas were there is a great exposure the skin colour gradually turns dark to protect from skin cancer and sun burn. Darker skin equals thicker skin. The chance of skin cancer in these areas, like Africa, were the sun is strong to dark skinned inhabitants is less likely than to those who are born albino. This is an example of natural selection; if those who are bone albino in Africa, do no have much of a chance to live into their late 20's early 30's if they are exposed as much as those around them. Now think of it, if in areas were it is hot with much sun exposure we have dark skin, where would we have evolved to have lighter skin? If you think of areas such as Russia or Europe, you would be right. In those areas the inhabitants do not venture outside much mostly because of weather. When they do they need as much vitamin D from the sun as possible, which is why they would evolve to have lighter skin so the sun can get more easily into the skin. The natural selection factor for those who have lighter skin, mostly has to do with birth. The lack of vitamin D can not only lead to low birth weight in babies, but can also lead to problems in childbirth that leads to death. Other side effects of not enough vitamin D in light skinned humans, is it can lead to a bone disease called rickets (softening of bones which leads to bowed legs, and deformed pelvis.
       With all the evolution our species, Homo sapiens have gone through, we cannot possibly have room to evolve more. But frankly, it is possible. Let us go back to the evolution of technology example I gave at the beginning of this blog. You would think that with all the attention we are putting into having other things evolve we have stunted our own evolution. But what if, just what if we evolve even more to fit with the technology we helped evolve? Some theorize that our eyes will become bigger because of technology, but I theorize that they might get smaller. Think of what happens to your pupil when a light is shined on it, it gets smaller. If anything, bigger eyes would have proved more useful in our early evolution to make seeing predators easier. But now, when we are safe in our home, at work, at school, in front of a bright screen, being a lap top or phone, we have no need to be hypersensitive about our surroundings. Combine that with the brightness of our technology, what other conclusion is there that our eyes will slowly become smaller as to focus on the screen we have been looking at. Although, the kind of extreme physical change will take thousands, if not a million years, to occur; if we make it that far. That said, our own species, Homo sapiens, is still a very young one. For example, the neanderthal, they were on Earth longer than we have been.
       I hope that you have enjoyed this blog. Please feel free to comment on what you thought of the blog, or other physical anthropological subjects you would like me to cover. Also, I would like to know how you think we could evolve. 

      Have ever wondered how those scientists on shows, like on Bones, identify a skeleton as male or female? Read on and I will tell you just how they do it. This process is called “sexing.” Now, “sexing” can never be called “gendering” or of the sort because they are two totally different things. Gender is how an individual sees themselves, whether or not they get operations to change their physical appearance. But sexing is more than skin deep. No matter how many surgical procedures an individual undergoes, no amount of surgery could change their skeletal make up by which they are sexed as. Let me start with the male skull.
       The reason I am starting with the male is because it has formations the female skull does not. If you would look at the picture below, you can see the ridges on top of the orbits (eye sockets). This ridge is exclusively for the male skull. The mandible (lower jaw) is also a more square shape towards the chin. There is also another formation. When looking at the male skull from the side there is a notch towards the bottom of the skull, but not all the way towards the bottom. On the bottom of the skull that is more evidence that the skull is male. On the bottom there is something physical anthropologists call the Mastoid process. This part of the male skull is much larger than the female, which I will speak of soon.

       Next up how to tell if the skeleton is male is the pelvis. I must say, it is good that the male and female skeletons can be told apart by more than just the skull; because sometimes the skull is not accessible. This looks like a normal, pelvis, right? Nothing weird...for a male that is. After these pictures concerning the male I will get to the female, but before I do, pay attention to how the male pelvis is closed. The sacrum and coccyx (the tail bone) is bent far ahead, and the ilium (the wings of the pelvis), are mostly closed in. The male hip usual lines up straight with the femur (upper leg bone), but the with the female it is completely different.

       The female femur lines up more beneath the hips than for the male. Reason being is the female pelvis is much wider than the male because the gap between the ilium is open to make childbirth easier. Also, you may notice in the picture below, the sacrum and coccyx are both much further back; again this is for the reason of childbirth. No matter if the woman had given birth in her life or not, these bones are predisposed in this way because early on in our evolution new children were vital for our survival. Albeit the mother would most likely die giving birth. Side note: when we were still quadrupedal (walking on all fours), the birthing was much easier because of that walking position. It is because we are now bipedal that birthing is much harder for human females. I have included a picture of a human female pelvis and a female chimpanzee pelvis at the end of this blog to illustrate my point.

       We now end where we began, the skull, but this time the female skull. If you remember the reason I started off with the male skull is because it has formations the female skull does not. Look at the picture below. The human female skull is without the brow ridges, the mandible is more pointy and rounded towards the chin, no notch towards the back, and the Mastoid process is small compared to the male. Usually when a human skull is found in a crime scene, or just by physical anthropologists , the first thing they look for to sex the body if the skull is available are the brow ridges. This one formation or lack of, can sex the skeleton. Although, with that said, if the skeleton is that of a small child who has not gone through puberty sexing that is much harder because their skeletons are not distinguishable to confirm male or female.  

       I hope that I have satisfied your curiosity on how these super-sleuths, otherwise known as physical anthropologists, can deduce the sex of a skeleton they are presented with. As a matter of fact you can feel these differences while humans are still alive. If you are a female, press down on your forehead above your eyebrow then move your hand til your reach the outline of your supraorbital margin (top of your eye socket). You may not notice any difference, but if you go to a male friend and, with his permission, feel his forehead you will be able to feel the difference in your bones. And if you are male do the same, but you will be able to feel a slight ridge before reaching your supraorbital margin. This time go to a female friend and feel her forehead, again with her permission. The only sexing bone you will not able to feel are the difference between the pelvis. 
Now there is another method to sex a skeleton, but this one requires much exposure to different skeletons to be able to sex them using this method. Reason being is that a lot of long bones (humerus, femur, tibia), look the same to the untrained eye. Those who have been exposed to bones can tell the sex just by the size of the long bones.
       As promised, below on the left is a human female pelvis, and on the right the pelvis of a female chimpanzee (as we began bipedal our skulls grew, but we were once as small as permitted by the pelvis to slip through without any trouble).
       Please feel free to leave me a comment either about this blog or on an anthropological subject you would like me to cover.