I am delighted with this question. Maybe this will sound weird to you, but there is Pierre Teilhard de Chardin, a jesuit priest who wrote extensively about "hominisation" and "humaniization" in the first half of the 20th century. There is one book that is particularly amenable to your question, La Vision du passé (1957). There is an english translation that is ok, titled The Vision of the Past. In this book, written under te spell of Darwinist theories of evolution, Teilhard de Chardin proposed that man does no evolve "physically": the human ability to develop tools that will improve the body's capacity to build and/or work has allowed for a fast-paced human "evolution" that has not had to wait for mutations or for the "survival of the fittest". Humans have evolved through the invention of tools that act as prosthetics of the body. Le Corbusier probably read and appreciated Teilhard's proposal. When Le Corbusier pondered about "primitive man" he said that "There is [or was] no primitive man. There were primitive resources. In man, the idea was strong from the start." The invention of resources [tools, etc.] was humanity's answer to the challenge of being in the world. The human body did not need to be strong in order to survive: humans had a peculiar intelligence, accumulative memory, imagination, with which we were able to creatively transform the world's materiality into tools that would allow us to build shelter.

There are several books that could help you see through this huge question you have posed: Jo Odgers et al, Primitive. Original Matters in Architecture [Rouledge, 2006], which I believe is out of print. It has a great bibliography that could be of use to you.

It bears noting that apparently humans at first would "find" shelter (caves, huge trees, tree bark, even the slightly-fired mud used by Tierra de Fuego's inhabitants to cover their bodies during winter, as described by Charles Darwin in his Voyage of the Beagle. It bears noting that when Odysseus lands in Alcinoos' island after a shipwreck in Homer's Odyssey, he covers his naked body with mud and leaves to fight the freezing weather. Dress can be interpreted as shelter also or, as Renaissance architecture theorist Filarete brilliantly proposed in one of his drawings, just covering your head by joining your own two open hands to form a gable. 

Great question!

The use of tools could now be found already in the Lomekwi-culture, 3.400.000 years ago in Ethiopia when we have been still very close to the apes.

In the Olduvai-valley 1,800.000 Years ago, humans have been sitting in the trees to select the animals they wanted to hunt, passing underneath. Then may be they have been sleeping there as well?

Going beyond caves and guessing: The Neanderthal men have been digging "earth-nests" and covered them with branches to form a hut. This is proven, the entrance was to the east.

The difference I mentioned persist, dear Thomas. What I can gather from your examples is that humans started to differentiate from other "animals" very early and, I must say, very emphatically and creatively. We've come a long way in just a few millennia and we did not have to be strong or fit to survive. Maybe Darwin should have counted intelligence as a "physical strength! He actually witnessed how creatively the "fueguinos" from Antarctic Chile "dressed" themselves in a kind of clay pot to survive the violent winter. Your example of the Neanderthal's orientating their huts towards sunrise  shows precisely my point (a similar case is examined by anthropologist Pierre Bourdieu in his much-discussed study of the Berber house: the role of the sun in the orientation and symbolism of the house; of course we can also remember that all medieval gothic cathedrals have their entrance facing the west, but once you are inside you walk towards sunrise...). I suggest a reading of Norbert Elias book on the measure of "time" —Über die Zeit, 1984—and the slow development of what are the uses of time: it has everything to do with how we humans started to associate very complex concepts from very early. The issue is not what archaeological material you can bring to the fore. The real issue is how to interpret those materials. That is was Teilhard de Chardin did: interpret information in a new manner, which is my suggestion to Chloe. I am not saying that he was right, but that he was developing a research tool that I still find very valuable. Thank you for the conversation! I'm learning a lot here! 

I normally reply individually to each of those who have responded but maybe this will be easier and just as conversational.

@Thomas and @Lilliana: I find your ideas intriguing. There are still many cultures that climb trees and very well without much evolutionary changes between cultures. I may not have as flat of feet but if I practice (as it is not my culture), the skill is the same. With my professor I actually questioned the relation of tools. We have seen ancient tools that are similar to our own modern tools such as the knife, club, or hammer. The argument I had though was to determine why we would automatically assume that the "hammer" is truly a hammer. Why do they need a hammer for a cave dweller? They aren't building anything (nails?). Who is to say that the cave was for special occasions and not just for dwelling. That would explain burials, drawings, and even food prep. Even our own modern day practices imitate the same traditions, we gather in large buildings, prep, eat, feast, and even sleep (i.e. Thanksgiving). We also gather, sometimes at the same building, for worship, ceremonies, weddings, council meetings, private interviews, etc. Thus the argument could be that the did dwell in caves but what if that is not considered living there (compare modern day work and home environment). Maybe they did live in trees but gathered in caves. Eventually they did actually live in caves (because of convenience, they were there all the time anyways?) but that wasn't its original purpose.

It is also fair to argue why the east? Is it because of the rising sun and the start of a new day? Couldn't they get the same sunlight facing NE, SE or even strictly N or S? The sun is pretty big and the horizon is vast. In which case, wouldn't this be where religion was actually rooted? Based on religious practices, their homes and temples face the east, the rising sun as a symbolic gesture, still practiced by some. How would they know direct E anyways? Being so close to animals wouldn't they go for convenience and ease, especially if the earth or mountain was fairly different material composition?

@C. Lewis: I am a Masters student at the BAC studying DHH (Design Studies for Human Health). Currently I am in a Human Behavior class, thus this particular relevance, but I have been pursuing the thought process for a few years now (probably since 2011-2012, before 2013 my Bachelors graduation). This research project is relevant to my research and eventual niche for the long run.

My background includes an Interdisciplinary program combining Art and Psychology. I was an Fine Arts Major, started taking health and psychology classes (pursuing CAM: Complementary and Alternative Medicine) where I discovered PNI (Psychoneuroimmunology) through which I started pursuing Expressive Art Therapy. Then through many other research avenues I discovered the philosophy that my entire world is a canvas and why not build therapeutic architecture?

There is much more to my program than just a nice thought. There is science behind this and people with need of better design elements based on their situation. The avenues could be psychological and physical whether it is a mental disorder, an allergy, disability, age, or something as simple as the common cold, stress, and depression. By understanding the root of our practices, culture, understanding, beliefs, etc. (thus the anthropological and archaeological research) we can understand the thought process, behaviors, needs, culture, and even unnecessary elements to our built environment, which could be argued very traditional, even "genetic." Is architecture just an art form or is there a reason (psyche, spirit, or physical) to our habitat. Are we making it harder or worse for us or is it just mental or personal? Many of my questions stemmed, or will stem, from this branch of thinking to fully understand what I can do for another in my line of practice.

Facing the orient (hence, the verb, "to orientate") is usually a combination of necessity and symbolism, as so many experts have stated. The issue is whether there was a symbolic instance already at work when these Neanderthal huts were "oriented". It is not true that any position of a house is the same vis-à-vis the sun's path: It depends on when do you need light the most: usually in the morning. when you are preparing to got  out to carry out some activity. Besides the fact that sunlight wakes people up and is a marker of time. Hitting nails is not the only thing a "hammer" is useful for: you can use a hammer-like object to flatten materials, to drive objects into the ground, to hit away any obstruction on your path, to reshape objects by clobbering them, to kill or numb animals or enemies... to ground hard nuts or other food... If you cannot identify the "hammer" as such, you can possibly identify "hammered" objets, or objects that have been reshaped by deliberate impact, menhirs may be an example, arrow points too, as well as neolithic stone cutters.  Deliberate orientation has a huge bibliography, with architectural and anthropological proposals, as well as "primitive" tools, whose bibliography spans quite a lot of specific or related subjects. On the other hand, most caves that contain traces of human activity were either used for diverse purposes or do not bear concrete evidence of continued habitation. Il could be a rather recent myth to say that caves were the first human shelter. The ancient Greeks used to mock Ethiopians because they were primitives who lived in caves ("spelunkai" in Greek), according to Thucydides. That, evidently is not true. These subjects should not be taken lightly, dear Chloe. Best regards!

Thank you for the feedback. It is true that hammers could be used for more and you pointed out very obvious ways that it could have been used. I failed to use more critical thinking in identifying more creative ways to survive. That could possibly be from the modern era where such things are so obvious they are forgotten. I also realize that this is not to be taken lightly but my curiosity and questions still push on and with little restraint. I will have to do more reading on these studies as it is a subject that has not been touched in my life since grade school. Thank you for your continued input Lilliana.

Chloe, these are important questions for me because I teach architectural history and most programs shun this topic that I find essential for the education of an architect. Vitruvius had to look back based on logic, just  systematically reducing the complexity of a Roman house until he got to what he deemed to be the "primitive house". But doing that, as you just said, talks about our present artifacts as the peak form in the evolution of an object, in this case, the "house" o "the shelter", which I find is the better word when touching this subject. This focus on the present as depositary of the necessary outcome of past commutative developments implies that everything that was the better solution to an ongoing challenge —let's say our houses are the perfect outcome of any and all houses of the past, the best that could happen— is what we are enjoying now. This lack of perspective, which is the offspring of the idea of (lineal) progress concocted during the Enlightenment makes us blind to archeological findings that fall beyond the present architectural imaginary. This also has a terribly racist slant: the idea that the present Wester civilization —considered white, educated in a specific way and having the certainty of its superiority above any and all other cultures— is the best that could have happen. If our idea of house is considered as the best possible house for humanity, our archaeological and anthropological enterprises are doomed to ignore anything that does not lead to this "optimal" conclusion of the evolution of the "house". Reason why Napoleon was impressed by the treasures of Egypt and could not believe that Africans con have built these monuments, or the idea that de Nazca lines were made by extraterrestrials. The hardest part of archaeological studies is to be willing to accept that the object we just unearthed might have nothing to do with the present, that this "primitive" object could very well had been "a road not taken" by humanity but that can teach us a lot about the past. Probably, Humanity has not followed a straight path to the present. The mere fact that we refer to "prehistoric objects" means that history began with the invention of written language because objects cannot speak for themselves. And that's a terrible fallacy. Ancient objects are willing to speak to those willing to listen. 

Your class must be fascinating. Most of my historic knowledge comes from what I remember from grade school and then my Art History classes from college which touched base on architecture, anthropology, and other forms of history in the form of art, a popular representation of culture and movements in society. The challenges that society went through and the outspoken non-verbal forms presented by people both rich and poor. The thought process of what was beauty or what was accepted was challenged. Music did the same thing in its history but both of these, though related, is a separate discussion.

I had a similar discussion about race and evolution/architecture with my professor earlier today. Despite our cultural differences across continents and the span of years before contact was made, evolution did not change as it may have with animals. The evolution of intelligence is also debatable. It is good to consider, as you stated, that maybe what we are seeing is not the way it was used in comparison to our modern society. That being said, who is to say that they were much more advanced than we gave them credit for? What if it was culture that influenced their "primitive" way of life rather than the lack of "civil practices."

I had the opportunity to live in Indonesia for a year. It is a third world country although it has the technology and the ability to be more, culturally it just will not happen, at least in recent years. There is hope however with the slow progression of a more just government. In which case, is it a matter of cultural acceptance, cultural evolution, cultural disruption, cultural war or infringement? When living their, the architecture looks similar to that of Brutalism but without the "art" added. The colors are very bright and displays the culture but the way the buildings are structured makes any expat wonder where these people are being educated if at all (which the answer is barely and horribly done in comparison to other countries standard of intelligence, i.e. their idea of  graphic design, college level, in marketing is working with Microsoft publisher, something middle school kids do in the states long before they graduate high school.) By culture it is easy to see them as without logic or common sense. In some cases I had to agree that the intelligence just wasn't there. However, they have survived without help for many years despite the lack of freedoms and being possessed by other countries for many years (a huge influence on their idea of way of life, thus architecture modified to fit that lifestyle thought). Although their life expectancy rate is still fairly low in comparison to world demographics (60 y.o.) based on life choices and cultural "lack of evolution." On other islands, they may still have brutalism like structures but it is a matter of economical availability. Otherwise they would be living in bamboo and grass huts as you would see in more "primitive" cultures. It is good to remember though that this is also a whole other climate. I would not find a bamboo hut in the Rocky Mountains of the US. They engineered and adapted around their environment and have some things that are just absolutely brilliant and should be accepted in other countries.

I believe that the exotic outlook is also what holds the appeal and architectural and cultural adoptions in societies as they cross over through various interactions. Most of our architecture has stemmed through that as we can see through the reins of various kings, rulers, and emperors from the Greek, Roman, British, Spanish, Aztec, and other reins as each personality and conquests of each ruler takes hold. Architecture could be seen as another art form, used to emulate culture and it's greatness.

Hi Garcia

You have raised too many questions at the same time- for which you will find answers in prehistory/ palaeoanthropology books and journals. The discussion could be more focused had you raised only one or two related issues. Otherwise all of us will go astray and will address different points.

Anek, I do raise a lot of questions and you are right, people will be addressing different points. Maybe it would be better to ask them separately but I did it this way because of how they are related and interconnected for the sake of other researchers who are interested in the topic.

The main question is the rudimentary inquiry but the note was to hopefully dissect my thought process, which is how I normally write to myself. I am also open to a wide variety of perspectives. I personally simply do not agree that there is one profession that knows the answer nor is there a simple answer to any question. I also follow the advice of Richard Feynman, a theoretical physicist, "What I cannot create, I cannot understand." In other words, unless I explore the avenues myself, just trusting "truth" or just trusting the "textbook" will not be beneficial to my education. I have to truly understand it. Thus hopefully by opening other avenues and resources I can contemplate and look at the resources of others thoughts and not just my own.

However, I will separate my thoughts more clearly into separate prompts so as to make this more user friendly.

The issue seems to be primarily one of genetic inclinations.  For those I believe you would have to look to spiders, some insects, or birds, in which the building of shelters is more or less "hardwired."  In humans you are dealing with a different way of adapting to the environment.  Human adapt culturally, so what is genetic is the tendency to invent solutions to problems and share them with others.  A recognition of a need for shelter, and the invention of a solution, can in fact be seen already in our closest relatives, the chimpanzees.  When it rains, they will sometimes break off some small, leafy tree branches and hold them over their heads.  Culture is cumulative, so shelters become more complex over time and they adapt to the local environment and available resources.

Ronald, I am fairly interested in the perspective of genetics. I have thought about the idea of "instinct" and I like the term "hardwired" more. Humans are a unique species and it is easy for me to debate between apes and humans in relation to evolution because of the huge gap (unless I am just not educated in this missing information). I fail to understand how something hardwired just changed like a light switch. There would have to have been some evidences showing some process of evolution through anthropology and archaeology the same way we would observe bones. There would have to be some information out there piecing together the missing anatomy (not all the bones can be found or placed on the right organism, some have to be fabricated based on theory or probability etc. until discovered) of architectural evolution.  Even if it was evolutionary, as previous people have commented concerning animals solve problems and watch their elders, in most animal societies, how to solve difficulties by observation. "Monkey see, monkey do" thoughts.

I will have to read more on our ape "biological" ancestors. I know religion is a whole separate debate but the "nature of man" is very real. 

I also appreciate your restatement of culture. It is developmental and changes as we evolve and interact with other societies, thus the development of beauty or exotic over the static, fit for survival.

It is also good that you brought to my mind a memory from my Metaphysics Philosophy class. People are unpredictable. No matter how strict one can create a standard or guide from A to Z, the Human factor will always find a way around a direct process. Chaos must exist.

Sometimes we adapt, sometimes we force the environment into adapting to us. It has never been one-sided. I suggest you read Oliver Dietrich essay he contributed to another debate. It is most eloquent about human skills applied to transforming the environment at the start of the Neolithic. In his article he shows positive evidence that points to a high human capacity for abstraction and symbolism. The idea of "adaptation" should be questioned. It is too passive, too submissive in the light of strong archaeological findings to the contrary. 

Exciting! Thank you everyone who has contributed thus far. I will have a feast for my eyes with the list of resources and discussions received. 

Hi Chloe,

Your raise a lot of very interesting and significant questions. I know of no research that specifically focuses on an adaptive value of homes or shelters. But I have argued in my book The Evolution of Human Sociability that two  major factors in human separation from apes was the much more dependent state of infants at birth and the fact that humans can give birth much  more often than modern apes. This led to a number of changes, not the least of which was pair-bonding among mating adults, the enticing of help (fathers, sisters, grandmothers, brothers) by mothers into child care, and an advantage of leaving the offspring behind, safely hidden, while one or the other of the parents when looking for food.

I postulate a number of emotional and cognitive developments that would have been advantageous as motivators of the above (which do exist in modern humans but not apes). One is that pair bonding must have included a degree of secret sex even among lower status males and females because in apes dominant males and females tend to predominate, which might mean that a female who was attracted to a male who went to the trouble to construct a nice, semi-isolated shelter (and he was motivated to be a sort of home type who would more likely aid in child care as part of his motivation to construct a shelter) would be favored by selection. 

Given that the evidence is now clear that humans evolved in semi-swamp, wooded areas rather than in savannas, where building material and chances for isolation would be more abundant, might support this. The above would set in motion selection pressures to build more elaborate, more eye catching, more sturdy shelters. This (along with things like body decoration and tool decoration) would provide selection forces for design and fashion. 

If these motivators grew strong enough they could go beyond survival and reproductive advantage. So, we create not only reed huts but palaces, not only clothing but high fashion, not only rhythms beat out with stick on the ground but orchestras; and on and on. In this way motivations for design could have been one of the driving forces in human social evolution.

Whatever the case, status display is a major human characteristic, and that requires, decorations, building, buying these for a lot of money and showing them off. Among modern humans being able to do these thing as well or better than ones peers certainly gives reproductive success; design certainly is significant

Best wishes,

Ron

Ron,

I like this idea. It also helps answer one of my other questions as to how culture may have started. I will have to look more into the resource you have mentioned as well. Thank you so much!

Thank you Ivo. I will be reading this thoroughly. I also understand the time change and being on RG at 2AM anyways. At least this is a worthwhile site to be occupied in at that time of night. Enjoy your rest.

Dear Chloe. Just a comment on living in caves. Caves are relarively rare so not many homo Sapiens , coming out of Africa, would have lived in caves. The reason human remains (including other species of hominins) are found in caves is because they stand a far better chance to be preserved there than would human remains ( including shelters) in more exposed areas. Nevertheless, caves when they were available were convenient shelters from the weather and predators, which is why one gets caves, like Swartkrans in South Africa, which have long histories of occupation by homo Sapiens and earlier hominid species

Johan,

Thank you for your contribution. It would make sense that caves were for convenience. What I still find curious however is how we evolved from caves to the architecture we have now. Each region, of course, has different landscape and materials. They would have to use their resources but even in cultures, many don't hold to their "original" housing techniques. We normally see just the decor and imitation especially in commercialized works. If caves did become permanent then why move out of them? Why bother to put in the effort to make a stone/brick house? Why stack logs and sticks for permanence rather than convenience for survival? 

There are no caves on the Africa savannah where we probably evolved. And there are not many caves in most areas. So apart from a lucky few who got to live in caves, most of our forebears had to make do in the open. And so we started to make shelters from the rain in Africa, and eventually the snow in Europe as we spread. It is because we can build shelters that we were able to take over the world. 

I like the topic and the guilt free questions. The participants are swell as well. So I will indulge. But first you all need to contribute to the issue below as well. It is obtusely related :-)

I have a lot of reading and reviewing to do before commenting. I'd like to avoid the veritable "foot in the mouth" syndrome if possible. LOL :-)

https://www.researchgate.net/post/Genesis_Fact_fiction_or_faith

I would work backwards.  We build arid cliffs and caves in cities today, adjacent to water, typically within 100' or so of sea level (or local lake level).  We gather in communities, large than family groups, but only recently in our mega cities, when technology has allowed us to bring resources in and wastes out much faster/farther than before.

There is a hypothesis that the reason we went 'out of Africa' was because we developed a form of cooperation that allowed larger groups than just close familial bonds allow.  Thus our ancestors wandered around in groups of families, meeting up with isolated families, and became the dominant culture. 

Shelters reduce the time required for people to meet their needs of homeostasis and security.  Simple branch and bark structures can be built with practically no tools and shelter a large family group.  I don't know if it would be sufficient to shelter a entire village.  If they were not, then new construction methods would be required, leading to 'architecture'.  

I understand there is a home on Vancouver Island that has been occupied for about 5000 years, being rebuilt in the same location every 5 to 10 years.  It can be disassembled, worn/decayed parts replaced, and reconstructed by a small group of young men in a weekend.

In Ontario, the people of the Anishenabe First Nation would build a family home by bending 8 poplar poles into a dome.  It would be tied together with wet leather, and covered with hides, bark, and earth.  Very much a dome, with an advanced hunter-gatherer society.  I would think in a paleolithic agrarian society that is not nomadic, the construction of solid structures would be an obvious evolution, leading ultimately to adobe and stone materials in the dome.

To throw in a little more historical content. Our nearest living relatives - the orangutans - also construct shelters with floors, roofs, and walls - effectively tree houses. There are variations such as sun shade shelters, but if one wants to think of this as instinct then it is certainly a species characteristics. Other great apes construct nests, even on the ground sometimes as in some gorillas (or chimps - don't recall which). But it is the orangutan that constructs the house - at least a great ape level of house - and this without a fully opposable thumb. With the evolution of the grasping hand in hominids there is no necessary known reason why these hominid did not continue to build tree shelters, but even with a similarly sized brain their new dexterity would have the potential for construction of a more elaborate structure. When humans evolved the modern terrestrial foot it may have still been the case that they continued to live in trees -  at least in the initial forest habitat. It is possible that preference for terrestrial housing did not occur until there was sufficient defensive ability. This model has been most extensively argued by Dr. Donald Perry. He has also argued that neanderthals were arboreal dwellers and not primarily cave dwellers, and their demise was at least partially in consequence of climatic deterioration and loss of forest habitat. 

Don Vannelli mentions pair boding among adults as a human developments, but it does occur in orangutans, although usually of comparatively shorter duration. However, modern orangutan habitat is relatively marginal and geographically restricted compared with pre-European colonial times. Even in the 1800's there were observations made that referred to seeing 'family' groups, but now there is no way to verify.

The beginnings of a decorative 'instinct' is seen in orangutans where individuals will sometimes drape vegetation over their bodies before visiting another orangutan.

That is an interesting thought and resource. Have orangutans always built with roofs, floors and walls? I know about the ape nests, we don't nest unless it is for a babe or sleep. I guess it would make logical sense to construct that kind of protection. Did they see us make it or has it always been just logical construction, basic needs of survival/comfortable living.

Orangutan housing has alway been that way. It has not been copied. The term 'nest' can be problematic. After all, a human house might also be called a 'nest'. I presume because great ape resting constructions involve interweaving of branches like in birds the term 'nest' has been applied. I prefer the general term shelter, and when hominids came down from the trees to live on the ground they brought their shelters down with them - in my opinion.

It makes sense. I guess a lot of our species may remain a partial mystery.

Culture has played a prominent role in the evolution of Homo sapiens. Within their groups, individuals often have multifaceted roles, based on age and gender, later humans began to hunt even the largest animals on Earth. The food chain processes progressed from gathering, hunting, agriculture, food processing etc.,

https://www.google.co.in/url?sa=t&source=web&rct=j&url=http://www.cabrillo.edu/~crsmith/Evolution_Cultural_Behavior.doc&ved=0ahUKEwjx59zrnLTLAhXCkY4KHUsLCRk4KBAWCBwwAQ&usg=AFQjCNHaKzswqvo_HXi-iJLaiJ3Fuc_eWQ

Hi Chloe,

have you seen this article? It is does not discuss about humans per se, but about the lower extinction risk of species which "sleep" i.e. hibernate, go to torpor or "hide", like use caves, tunnels or hollow tree trunks to get extra protection against environmental stress or predation.

Liow, L.H., Fortelius, M., Lintulaakso, K., Mannila, H. and Stenseth, N.C., 2009. Lower Extinction Risk in Sleep‐or‐Hide Mammals. The American Naturalist, 173(2), pp.264-272.

https://www.researchgate.net/publication/43072142_Lower_Extinction_Risk_in_Sleep-or-Hide_Mammals?ev=prf_pub

-Kari

Article Lower Extinction Risk in Sleep-or-Hide Mammals

Hi Chloe,

your question(s) are very complex ones. When talking about the "why" question, it is important to always keep in mind that following Darwinian Evolution the ultimate why question, which I gather is what you are interested in because you ask for evidence of a survival benefit, is always very hard to come by. It requires showing that a behavior has direct fitness consequences either by increasing reproductive success or by decreasing predation risks. So why did humans began living in shelters, and eventually building shelters? If asked for the origin, probably a combination of thermoregulatory and predation avoidance are the most likely candidates. There are a few studies on nonhuman primates that suggest these reasons for the use of caves by nonhuman primates (e.g. Limestone cliff - face and cave use by wild ring-tailed lemurs (Lemur catta) in southwestern Madagascar, by Michelle L. Sauther, Frank P. CuozzoI, Ibrahim A. Youssouf JackyII, Krista D. FishIII, Marni LaFleurIV, Lova A. L. RavelohasindrazanaII and Jean F. RavoavyII; 2013). Cave use by Fongoli chimpanzees probably has an additional effect, because it allows chimpanzees to hide from humans as they share their habitat with human populations. These chimpanzees also travel substantially at night, which other chimpanzees don't do, perhaps for the same reason. It is reasonable to assume that early hominins began using caves for the same reasons, but humans have probably further developed cave use and added making caves 'living space', which chimpanzees and other nonhuman primates don't seem to do. They do not alter the 'cave space' but only temporarily use it. Once caves had become 'living space' it is not so difficult to see how it further developed, step-by-step of course. Functional use is the most likely driver for modifying caves and eventually building free standing shelters. Relating these hypotheses back to your functional question "why" is difficult, because although we have these nice ideas about the use of caves and shelters there is - to my knowledge - no hard evidence that these behaviors indeed increase survival of those individuals who perform it. Thus, was living in shelters a necessity because it helped early hominins to better survive or reproduces? That's an open question.

Ulrich certainly points to the empirical impossibility of resolving why questions centered on assumptions of functionality. But further the initial questions can introduce another bias. For example, the question “So why did humans begin living in shelters, and eventually building shelters? “ Well, maybe the answer is that they did not “begin” doing so at all, but inherited the behavior from earlier ancestors, ancestral origins for which go back to the great apes if orangutans are anything to go by with their construction of tree houses (so-called ‘nests’ that may include floors, walls, and roofs). And for the question “was living in shelters a necessity because it helped early hominins to better survive or reproduce?” it might be said that early hominids built shelters and as a consequence they may have better survived or reproduced than without.

 As noted in other posts, cave dwelling seems to have been a sideline habitation, and even for Neanderthals for which cave dwelling has been regarded as their mode of habitation, there is insufficient evidence that it was a primary mode, and other evidence that they were principally tree dwellers.

Hi John

yes, interesting thoughts. If you consider human shelters extensions of great ape nest construction, then I certainly agree that humans probably did not 'begin' living/building shelters but inherited this ability (mental and physical) already from a common ancestor shared with great apes. I am unfortunately not aware of great ape tree-house building and would be grateful if you can point out the relevant publication that has extended nest construction in orangutans to habitually include structures with floors, walls, and roofs?

You suggest that "early hominids built shelters and as a consequence they may have better survived or reproduced than without." Sure, we cannot know if shelter living was a by-product of some other RS/survival-relevant behavior and thus may itself have been neutral regarding hominin RS/survival until it was co-opted into becoming RS/survival-relevant, but it cannot be excluded either that living in shelters initially increased RS/survival perhaps due to reduced predation or other yet unknown benefits. It seems to me both scenarios are equally possible.

At the end of your comment you mention that some evidence exists Neanderthals were principally tree dwellers. This is news to me and I would appreciate if you can point me in the right direction of a published study that has found evidence for this hypothesis.

Thanks, Ulrich

John n Ulrich- I saw some video wherein orangutan is shown to prepare a nest on tree. Could apes not  watch the bird nests as a safer dwelling?