Re: "People first lived in Britain about 700,000 years ago" ?
- From: Matt Giwer <jull43@xxxxxxxxxxxxxxxxxxxxxxx>
- Date: Tue, 18 Mar 2008 22:47:21 -0400
bent wrote:
Looks like there are actually more than 3 motors on the shuttle itself, but you get the idea:
http://www.flickr.com/photos/trinity/170177/
The whole package:
http://ca.images.search.yahoo.com/search/images/view?back=http%3A%2F%2Fca.images.search.yahoo.com%2Fsearch%2Fimages%3Fei%3DUTF-8%26p%3Dspace%2Bshuttle%26fr%3Dsfp%26b%3D161&w=448&h=500&imgurl=static.flickr.com%2F53%2F184713390_6d3e50ef38_m.jpg&rurl=http%3A%2F%2Fwww.flickr.com%2Fphotos%2Fdoneastwest%2F184713390%2F&size=163.2kB&name=184713390_6d3e50ef38.jpg&p=space+shuttle&type=jpeg&no=172&tt=326,292&oid=d985504ce14d4a58&fusr=doneastwest&tit=Shuttle+Fuel+Tank+Camera.&hurl=http%3A%2F%2Fwww.flickr.com%2Fphotos%2Fdoneastwest%2F&ei=UTF-8&src=p Wow, a search of "space shuttle", images only, gives some very nice photography.
btw, being pertinent, I am beginning to understand the emphasis of the reference quote, but lets not get into details now (both sides).
Given what you have said below you have enough interest in learning not to be put off by the amount there is to learn. There is probably a single book or two which sum it all up but I have no idea. I simply read just about everything I come across in the sciences and this is one of the subjects.
One of the recent posts above mention the term subspecies. I think theres a lot of people right on track still wrt the original post (by me). I am just happily tagging along, but if anyone can imagine what my state of confusion is regarding how this species linkage works, please do expand if simple enough. Hate to push nmy luck. (wish I had that ref now) but the jist of it is like this (laymans terms): I was originally wondering what people were; now theres a comment on the 100,000 yr ago exodus of Homo Sapiens out of Africa. Then theres the comment on Homo Sapiens possibly existing in Africa 196,000 yrs ago. So far I am not confused, but I will be digging into these links more soon.
The more recent date is physical evidence. The older date is evidence from genetic drift which is still a new science. It assume a constant drift rate which may not be the case immediately after speciation occurs. Follow the findings in the field unless you go for a degree and get into it yourself.
I am not sure if the following is established science yet, or literally even a question. e.g there cannot be two species existing at any one point in time that both contributed to our current embodiment.
By definition you have different species when they cannot or do not interbreed. So different species cannot contribute to each other by definition. That is not to say the definition is satisfied. There is a huge variety of canines in the world and last I heard they can all interbreed and frequently do. But even where their ranges overlap, coyotes and wolves for example their environment selects the form of the survivors from a mixed litter. Point being even though there are differences in form speciation has not occurred. Given all the types of humans around the world we can all interbreed so no speciation has occurred. Applied to a later comment of yours, subspecies is not a defined word but a convenient term which could be used interchangeably with race when talking about Sapiens. However when that is said someone with a hangup about WWII goes ballistic so expect it.
Never the same. Never leading in a ny way to us: so there is a route. iow all others don't count as "us".
What you originally clarified for me was that you were interested in Sapiens not hominids in general.
But theres just so many (intriguing) names and to me, unknowns thrown around, I get lost, and I am not learning about this specific quest I started - soon I'll be on my own, don't worry. Looking at the evolutionary "tree" as a traingle it can either be oriented with the peak (one) at the top and the many at the bottom, or the many on the top, and the one at the bottom.
Keep in mind we are not the peak of the tree just the longest branch. Those near us died out. Neanderthal being the most recent die off we are sure of at roughly the end of the ice age. Evolution has not peak, no goal, no direction.
Where did we come from? Maybe the term subspecies could be used.
As above no such thing as a subspecies. One could consider coyotes and wolves to be subspecies and Europeans, Orientals and Africans to be subspecies. With canines the environment can select those which will survive from the litter. Humans don't select that way. While it might happen eventually our single birth and proclivity to marriage means an Englishman in China will have his genes diluted over the generations before there might come a chance for some form of natural selection. And with that there appears to be no natural selection means for humans in nature. All the races can adapt to any environment and human reproduction is so slow relative to our lifetimes that we can't observe these changes if they are occurring. And before Darwin no one was paying attention so we have less than 200 centuries of observation, maybe seven generations. If a dog lives ten years an intelligent one could observe nine generations. For us when people have great grandchildren, three generations, it is worthy of note.
Because can a being (thing) suddenly appear out of nowhere?
Obviously that did not happen. The speciation of Sapiens would have likely occurred when a tribe or clan came to be separated from the main body of the mass of the species. While separated some genetic change occurred that spread through the group. And the narrow family characteristics of that group were reinforced. This is just like tall parents tend to have tall children. Now as soon as that group rejoined the whole their genes would have been absorbed back into the entire population. Therefore something had to have happened in this isolation that prevented interbreeding. Figure out what that was and find a way to prove it and your name will go down in history alongside Darwin.
Whatever it was it became reinforced within this population like being tall. And because of the speciation event it was kept within the group.
But here is the problem with that idea, the genetic variation of Sapiens in Africa is huge compared to the trivial amount of variation outside of Africa. So it could not have been a small group that replaced all previous near humans as the genetic age of humans is less than double the out of Africa age. This requires some hugely beneficial genetic change that spread to the entire African human population without exception. It had to be almost crucial to survival. If it were not there would be no reason for it to become dominant any more than blue eyes.
But wait, there's more! As species do not exist unless they can survive whatever this crucial thing was could not have been a correction to a deficiency in survival potential of the general population.
Welcome to the wonderful world of impossible things that really did happen because we are here to see they did happen.
A long time ago, 4 billion years, I'll admit it wasn't one thing, but there were conditions condusive to this specifc start.
From what we have found it appears life is a natural phenomenon within some very wide physical conditions.
Is this still a question? I don't know if this (maybe the term subspecies of ....Homo sapiens) is a cop-out. Is there a rule about this: how can I think of something being related to, but not really being a member of "people"? While I want to learn about everything, I want to know "us" and how to get there. What exactly does it mean to be a sub-species. Does one say I don't know, we're just playing around with ideas here, or is there a rule, and is it proven empirically?
You need to read a lot more and think about it a lot more. Don't go with the journalism major science writers. Look for anthropologists talking about what is going on in plain language. And keep in mind there are fads in this field and that not everyone who claims to be an anthropologist really is. If what is said matches any current fad or political theory it is essentially guaranteed to be wrong.
We really have no idea why Sapiens became dominant. At the time it occurred the only competition was Neanderthal which appears to have been a European development of some prior African origin just as Sapiens. Africa is not a place conducive to preserving fossils so a lot more might have happened we have no idea about. Because of that it takes a long time for a significant amount of remains to be preserved not to mention the problem of finding them. Consider Tyrannosaurus was around for 20-30 million years and we have two mostly complete skeletons and ten partially complete skeletons and the rest are single bones here and there. How much does one expect to find from species measured in hundreds of thousands of years? It is hard to push back all hominids even ten million years.
All of that leading up to the problem with finding evidence of the actual event of speciation. I gave first the one way we know speciation occurs right from Darwin's seminal work and then the reason it cannot have happened that way of Sapiens because of the variation. (BTW: A single "tribe" of chimps has more genetic variation than the entire human species including Africa.)
Once I read a description of the evolution of intelligence. There have been millions of species where the selection was not for intelligence. Only hominids appear to have selected for intelligence so whatever caused that is extremely rare. Given all the hominids over millions of years we see that they were all but one failures despite intelligence. And then looking at Neanderthal we find intelligence is not simply the size of the brain but something more and we have no idea what that is.
The route from lemurs to us had to have been a long series of rare selection events such that at the end of it there was a species that no longer needed selection events but could take charge of nature and avoid being selected out. And even then do it in a way that even the closest Neanderthal disappeared and even Heidelberg man changed drastically before taking over the world.
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There is no official 9/11 theory.
An official theory exists only in the minds of those who attack the
questioners.
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