The Science of Human Evolution

[sayak83]

I thought I would create a thread tackling the overall science of human evolution as whole instead of going around replying to isolated topics. I will discuss what scientists believe about human evolution and why they believe it. i hope to go over this as coherently as possible and answer any relevant questions that come up.

I am an interested person trained in science in general but not in biology specifically. So anybody who adds to what I am saying (based on what I have read ) is welcome to contribute.

1) Place of Humans among the biological world.

I have often seen people squirm when someone says "humans are apes". I have never understood the reason for this as nobody raises even an eyebrow when one says "humans are mammals." Both the word "ape" and the word "mammal" single out a group of animals and places humans in that group due to similarity of features.

So lets back up a bit. Humans, monkeys, apes, lemurs and several other animals like lorises, tarsiers and bush babies belong to the group called Primates. This group of mammals is very old, with earliest ones identified from 65 million years just after the dinosaurs went extinct and mammals became numerous. There are certain characteristic that primates have which other mammals do not. And humans have them all:-

1) Hand and feet have the ability to grasp with opposable thumbs and great toes.
2) They have nails instead of claws.
3) Movement is dominated by the hind limbs rather than the forelimbs. Forelimbs assist the locomotion, but both power and balance comes from the back legs. Humans have moved this to the extreme by walking exclusively on two legs.
4) Body is held fully or partially upright during movement.So most primates can and do walk bipedally sometimes in briefer or longer spurts.
5) Eyes face the front and are very well developed.
6) Sense of smell is comparatively less well developed.
7) The snout is short and the teeth are less in number than other mammals. Teeth number has decreased from 44 to 36 (new world monkeys, lemurs etc.) and then to 32 (apes, old world monkeys).
8) Larger brained in general than average mammals.
9)Are slow to reproduce. Smaller size of the litter with relatively slow growing infants.

As you can see, humans share all these features and hence are called primates.
In addition apes have certain specific trait that no monkey has
1) No tail.
2) Fully rotatable shoulders
3) Flexible wrists
4)Bigger brains than monkeys
5) Bigger bodies and different skull structure.

The changes are thought be brought about due to the reliance of hand and feet only for moving from tree to tree as they had no tail.

As one can see humans have the distinguishing traits of primates and within it, apes. Then humans are a group of apes.

Questions?

 

[AndromedaRXJ]

10) Defective Vitamin-C producing gene.
11) Lifespan is considerably longer than other groups of mammals, at least in relation to size (longevity seems to correlate to size in the animal kingdom, but even small primates live a relatively long time).
12) Shared social behavior and psychological characteristics. A lot of our psychological and social characteristics that we associate as being a human trait, is really a primate trait. E.g. jaws dropping when surprised. Hugging. Children primates staring at an adult doing an interesting activity with a locked gaze.

 

[Skwim]

Curious, what field of science are you trained in? I assume you don't have a degree in any of the sciences.

I also suggest that if you're going to be referring to the various ranks of mammals that you use the appropriate name, i.e. order, family, genus, species instead of the vague "group," which might be confusing. And a taxonomic diagram might be helpful to show why people refer to humans as apes, and why monkeys play no part in our ancestry. Otherwise, good start. And knowing some of the members around here, good luck.


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[sayak83]

Curious, what field of science are you trained in? I assume you don't have a degree in any of the sciences.

I also suggest that if you're going to be referring to the various ranks of mammals that you use the appropriate name, i.e. order, family, genus, species instead of the vague "group," which might be confusing. And a taxonomic diagram might be helpful to show why people refer to humans as apes, and why monkeys play no part in our ancestry. Otherwise, good start. And knowing some of the members around here, good luck.


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Chemistry PhD.

I would prefer to use technical language as little as possible. The jargon is useful mnemonic to "store" long pieces of information on the mind of a trained practitioner, but not useful before you know it. I always think of chemicals as small dance groups, men and women linking their arms and making elegant dynamic shapes and the "chemistry" that comes from it.

 

[Skwim]

Okay, then I'll do it.

Why humans can be legitimately referred to as apes.

.​

 

[sayak83]

Okay, then I'll do it.

Why humans can be legitimately referred to as apes.

.​

Thank you for the excellent post. As people can see, the earliest branch within the group of primates is between the Lemur-like and Tarsier-like primates. The Lemur like one give rise to modern lemurs and lorises while the tarsier-like one branch more to give rise to monkeys/apes-humans. The evidence for this branch has accumulated recently.

One of the many reasons scientists believe that some kind of evolutionary method explains life is because the patterns found in the fossil record. Remains of animals found millions of years ago look very different than those living today. However as the fossils come from rocks laid down more closer to the present, many of the animals begin to resemble the forms biologists see today. This is true for the case of ourselves too.

In the earliest times after the extinction of the dinosaurs (65-55 million years ago), most of the primates that lived were quite different from modern varieties. But around 55 million years ago, fossils begin to turn up that look like ancestors to modern day lemurs and lorises. These are called Adapids, and the best preserved fossil is that of a species called Darwinius that lived 47 million years ago in Germany. It is an entirely complete skeleton, along with impression of fur and soft tissue, entombed in hardened shale.
https://en.wikipedia.org/wiki/Darwinius

Meanwhile a somewhat older fossil (55 million years), also encased in shell was found in China. This one, called Archicebus, is an extremely small little primate and have features common to modern day tarsiers and monkeys. It is considered to be one of the species of a closely related group that will eventually lead to tarsiers and monkeys/apes.
http://www.nature.com/news/oldest-pr...veiled-1.13142

The slender-limbed, long-tailed primate, described today in Nature1, was about the size of today’s pygmy mouse lemur and would have weighed between 20 and 30 grams, the researchers estimate. The mammal sports an odd blend of features, with its skull, teeth and limb bones having proportions resembling those of tarsiers, but its heel and foot bones more like anthropoids. “This mosaic of features hasn’t been seen before in any living or fossil primate,” says study author Christopher Beard, a palaeontologist at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.

Here we see that by 55-50 million years the ancient primates have divided into the two big groups into which all modern day primates belong. One group leads to lemurs and lorises and have species that look like Darwinius , and the other look a mix of tarsiers/monkeys of which Archicebus is a good example.

It is also important to note what is not found. None of the modern day monkeys, lemurs, tarsiers, apes are found. What are found are quite distinct creatures that have traits in their body that resemble the modern day primates in some respects. The science of modern day cladistics identifies and quantifies all these traits and thus places these ancient creature in "trees" of resemblances between themselves and the modern primates. There will be many creatures in the millions of years afterwards that begin to resemble the modern creatures more closely until there comes a time (quite recent) when the actual modern forms crop up. This is a prediction of and good evidence for the theory of evolution in the living world.

 

[NoGuru]

A bit interesting that we've dug deep enough to find dinosaurs but have yet to find the remains of the "missing link." You'd think we find those before we got to dinosaur remains, no?

This is all well and good, but a logical fallacy. The false cause fallacy. Just because things are related to each other does not mean one came from the other. We look at all the similarities between us and monkeys and say "Ah Ha! that's what we evolved from! Eureka!" You also share 50% of your DNA with a banana, and 70% with a slug, did we come from them? "No, because we share 98% with monkeys!.... we just can't find any proof"

A logical fallacy.

I'm not making the case that evolution is a hoax either. We've experienced evolution in recorded history so it is a thing... but to take that evidence and then go way back and try to determine the start of it all, especially just looking at similarities is (IMHO) research bias and is a logical fallacy.

Can I say "Well there's this book.." and say God created man? Well no, I wasn't there either, nor am I naive enough to think a single book has every answer, ever. Life doesn't work like that.

I'm not going to pick apart evolution from apes with any kind of evidence or reasoning because again... I wasn't there, nor was anyone else here, it's all speculation at this point.

 

[sayak83]

A bit interesting that we've dug deep enough to find dinosaurs but have yet to find the remains of the "missing link." You'd think we find those before we got to dinosaur remains, no?

This is all well and good, but a logical fallacy. The false cause fallacy. Just because things are related to each other does not mean one came from the other. We look at all the similarities between us and monkeys and say "Ah Ha! that's what we evolved from! Eureka!" You also share 50% of your DNA with a banana, and 70% with a slug, did we come from them? "No, because we share 98% with monkeys!.... we just can't find any proof"

A logical fallacy.

Both bananas and ourselves are descended from a common ancestral group of unicellular organisms which is why we share genes. Slugs too are related to us by a common animal ancestor in the early Cambrian era (500 million years ago). However those distant relationships are not the topic of the current post. So far I have presented the reasons why humans are classed into the category of apes (based on physical and bodily similarity). I also presented fossil evidence that primates, the group which all current apes, monkeys, us, lemurs etc. belong to- arose at 65 million years and branched into two at 55 million years. Without evolution, there is no reason for such patterns to be found in the fossil record. Among the primates, lemurs and everything else looks most distant to each other. Evolution predicts that in early fossils we would see a very ancient point where lemur-like and tarsier/monkey-like creatures would be first seen, much before any of the other later divisions are seen. This is what we find.

 

[metis]

I'm not going to pick apart evolution from apes with any kind of evidence or reasoning because again... I wasn't there, nor was anyone else here, it's all speculation at this point.

But it is speculation based on evidence, both in terms of the fossil record plus genome testing. The 6 million year old Chad find has so many shared ape/human characteristics that there's been debate as to how it should be classified.

However, in science, nothing is considered to be an unquestionable fact, and that would include a common human/ape ancestor.

 

[Jayhawker Soule]

Both bananas and ourselves are descended from a common ancestral group of ...

The phrase "slippery slope" comes to mind.

 

[Jayhawker Soule]

A bit interesting that we've dug deep enough to find dinosaurs but have yet to find the remains of the "missing link." ...

It's a bit interesting that you do not seem to know what you're talking about. You could start here, but I have little confidence that it will help.

 

[Skwim]

A bit interesting that we've dug deep enough to find dinosaurs but have yet to find the remains of the "missing link." You'd think we find those before we got to dinosaur remains, no?

First of all, "missing link" is a non-scientific term for any transitional fossil that has not yet been found. And in paleoanthropology, just as in all other areas of paleontology, there will always be missing connecting evidence of some kind between two successional forms. However, because the implied connection is so very strong, it would be perverse to withhold provisional assent, which is how science regards all facts. So, there is no "the missing link," but many missing links, everywhere---it just depends on how particular one wants to be. Are you looking for the missing link that stands between the fossils of Homo heidelbergensis from Homo cepranensis? Well, you probably won't find any---principally because Homo fossils are so very scarce. However, it would be dim-witted not to see the virtually certain connection between the two. Just keep in mind that within science absolute certainty is never claimed. Then there's the false assumption among lay people that fossils are there just for the digging. That if there's truly a "missing link" it would have/will be found. NOT SO. The discovery of fossils is largely a matter of educated luck. One looks for them in places most likely to contain them. But it's really a big crap-shoot, and to find a truly transitional fossil, even more so. As for the old creationist challenge, "Show us the missing link," in an 1863 publication, Charles Lyell, who helped found modern geology proposed that human ancestry must be very far in the geological past, and that the linkage between humans, Homo sapiens, and their predecessors was, as of that time, missing. This linkage eventually became known as the missing link. Since then many transitional fossils have been uncovered showing a graduated change in Hominid development. So much so that 'the missing link" in the creationist vocabulary has been pretty much expunged.

This is all well and good, but a logical fallacy. The false cause fallacy. Just because things are related to each other does not mean one came from the other.

And it might well be if the process of evolution, a well accepted fact within science, wasn't seen as the logical machinery that functions as the cause in "cause and effect." Like it or not, there is absolutely no reason not to think evolution was the driving force behind the differences in Hominids, particularly when those difference show such strong temporal sequencing.

I'm not going to pick apart evolution from apes with any kind of evidence or reasoning because again... I wasn't there, nor was anyone else here, it's all speculation at this point.

Which must also go for the Revolutionary War. Nobody can say it actually happened because after all, you weren't there, nor was anyone else here.


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[NoGuru]

Both bananas and ourselves are descended from a common ancestral group of unicellular organisms which is why we share genes. Slugs too are related to us by a common animal ancestor in the early Cambrian era (500 million years ago).

Sure, the abiogenesis line of thinking, and everything spawned from that. This falls on it's face though when you ask the question of why we have both male and female counterparts of the species. Something had to produce asexually to start, think cell division or even a hammerhead shark. If you subscribe to evolution in it's entirety, then at what point did a male counterpart spawn and then a female counterpart? Was it in a single generation?

I get that we're examining MILLIONS of years, so it's surely possible. From a commonly accepted viewpoint of evolution, it doesn't seem to make sense why it would happen.

So far I have presented the reasons why humans are classed into the category of apes (based on physical and bodily similarity). I also presented fossil evidence that primates, the group which all current apes, monkeys, us, lemurs etc. belong to- arose at 65 million years and branched into two at 55 million years.

No real argument here. Again I'm not saying it's wrong, but's it's a stretch to say the least. As is creationism or any model you wish to create to explain how everything became what it is now.

We took a portion of Darwins book and built an entire science out of it, throwing out much of what else he wrote. Isn't that the problem with religious zealots too? Taking words out of context?

Without evolution, there is no reason for such patterns to be found in the fossil record.

Perhaps evolution (as we accept it en mass) is preventing us from seeing the real reason.

Ever heard a "Ghost" recording? That static white noise they record and then claim (however true or not) to hear voices in it? What's interesting is how well adept the brain is at recognizing patterns. So let's say someone plays a recording for you. You hear noise. Then they say "Doesn't it sound like a voice is saying [whatever]?" They play it again and now you can make out those words in the noise. Now, once your brain hears that pattern, it cannot hear anything else in that pattern and will always recognize that pattern in the noise. It takes much retraining just to unlearn a simple voice in static noise!

Again, and I'll say this over and over again because I don't know, I'm not saying it's wrong. It's a stretch though. There are links, no doubt. Those links do not, however, provide a consistent picture. In my mind, it's an over lay of patterns to see what we want to see, just like creationism, flat earth rhetoric or anything anyone believes. We build a pattern and then find things to fit the pattern.

Among the primates, lemurs and everything else looks most distant to each other. Evolution predicts that in early fossils we would see a very ancient point where lemur-like and tarsier/monkey-like creatures would be first seen, much before any of the other later divisions are seen. This is what we find.

Which could very well be the answer we're looking for. Could be explained by a better hypothesis as well. A good question though is why we haven't found that "missing link." One would assume that there should be plenty of evidence and remains to support this. There's not. What about the rock formations in South Africa around Adam's Calendar? There are no remains at all from the "people" who created all that. The lack of remains suggests some sort of intervention. How old is the universe? And we think nothing else could have interfered with our progression? The biblical timeline (i.e. been here 6000 years) is wrong, no doubt there (the Sphinx, Stonehenge, etc shatters that). But it's dangerous to automatically jump to the opposite. Our society is dividing everyone into two extremes. Creation vs. Evolution... I'm with the taco girl, why not both? Or maybe even neither, who's to know? Joining a side because there's only two is stupid (and this isn't directed at you). If given only two options, perhaps we start coming up with different options, because life is never that easy.

 

[NoGuru]

It's a bit interesting that you do not seem to know what you're talking about. You could start here, but I have little confidence that it will help.

... how so?

Define evolution. Is it not the natural progression and changing of an organism to better adapt to it's environment? And I'm not here to advocate creationism. Again this is a huge problem of any system where you simply have two choices. If I say choice A is bad, then I must support choice B right? No... I couldn't tell you if either were right. I'm simply pointing out the fundamental principle upon which the theory is established doesn't match the life we see around us and doesn't necessarily seem to add up logically given said life. Nor does creation from a purely biblical standpoint... it's silly to say the least. I'm sure there's some truth to it... and I'm sure there's tons of truth to the whole evolutionary belief system... but choosing A or B when both seem flawed is stupid and a lack of imagination IMHO.

First of all, "missing link" is a non-scientific term for any transitional fossil that has not yet been found. And in paleoanthropology, just as in all other areas of paleontology, there will always be missing connecting evidence of some kind between two successional forms. However, because the implied connection is so very strong, it would be perverse to withhold provisional assent, which is how science regards all facts. So, there is no "the missing link," but many missing links, everywhere---it just depends on how particular one wants to be. Are you looking for the missing link that stands between the fossils of Homo heidelbergensis from Homo cepranensis? Well, you probably won't find any---principally because Homo fossils are so very scarce. However, it would be dim-witted not to see the virtually certain connection between the two. Just keep in mind that within science absolute certainty is never claimed. Then there's the false assumption among lay people that fossils are there just for the digging. That if there's truly a "missing link" it would have/will be found. NOT SO. The discovery of fossils is largely a matter of educated luck. One looks for them in places most likely to contain them. But it's really a big crap-shoot, and to find a truly transitional fossil, even more so. As for the old creationist challenge, "Show us the missing link," in an 1863 publication, Charles Lyell, who helped found modern geology proposed that human ancestry must be very far in the geological past, and that the linkage between humans, Homo sapiens, and their predecessors was, as of that time, missing. This linkage eventually became known as the missing link. Since then many transitional fossils have been uncovered showing a graduated change in Hominid development. So much so that 'the missing link" in the creationist vocabulary has been pretty much expunged.

I'm not saying "picture or it didn't happen," and I'm here to debate for the sake of debating... I'm not proving anyone wrong with anything I'm saying. I get that. Sparking debate

Now then; we've not found this transitional fossil, may not. It may not exist.

That would seem to indicate that massive changes happened within a single generation... doesn't this go against the belief?

I can see the argument that one generation could have produced massive changes in response to a global event... some sort of threat, but it would stand to reason then that we should be seeing those exact same changes today. Maybe not "today", but in the coming years when the climate is massively different, we should see some exotic breeds, no?

Which must also go for the Revolutionary War. Nobody can say it actually happened because after all, you weren't there, nor was anyone else here..

History is written by the victor. A conquering nation goes in and first destroys literature, wipes the other civilization out of history and then writes their own. It's entirely possible there never was a war. Just because some book said it happened and millions believe it doesn't mean a thing. Another logical fallacy and probably the biggest beef any non-[insert religion] has with [insert that religion again]. I'm not saying there wasn't, might want to clarify that here since my intent is being taken too far to one side. What I am saying is that we rely too heavily on the rules and regulations we've been given.

How's that worked out for us thus far?

 

[Skwim]

I'm not saying "picture or it didn't happen," and I'm here to debate for the sake of debating... I'm not proving anyone wrong with anything I'm saying. I get that. Sparking debate

In other words, trolling.

Now then; we've not found this transitional fossil, may not. It may not exist.

That would seem to indicate that massive changes happened within a single generation... doesn't this go against the belief?

I can see the argument that one generation could have produced massive changes in response to a global event... some sort of threat, but it would stand to reason then that we should be seeing those exact same changes today. Maybe not "today", but in the coming years when the climate is massively different, we should see some exotic breeds, no?

I'm sorry, but I'm not up to dealing with your lack of knowledge and understanding. Have a good day.


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[Quintessence]

Questions?

I'm going to be that bother and ask where all the citations are.

 

[NoGuru]

In other words, trolling.

..? How do you get that? So because someone plays devils advocate it's trolling? If I were trolling wouldn't you think my responses be a bit shorter and bit more poignant? Disagreement and wonder is trolling?

I'm sorry, but I'm not up to dealing with your lack of knowledge and understanding. Have a good day..

Well, when you are I'd love to hear an intelligible response. I completely understood what you said, I'm just posing questions. "If you can't explain it simply, you don't understand it well enough" ~ Einstein. If you don't understand it well enough, why are you getting upset when someone posts a question about it? That's like a martyr being upset because someone offended their God. If there is such a being, it certainly needs no defense, therefore their ignorance gives way to anger.

Which of my prepositions had anything to do with a lack of knowledge? I'm trying to open a discussion but just like religious zealots, I find more and more and "science" types are no different. "Agree with me and if not, you're stupid and don't know what you're talking about."

I've said several times I claim no authority, I'm simply trying to elevate the discussion.

Have a good day as well, and I do hope to hear back.

 

[sayak83]

I'm going to be that bother and ask where all the citations are.

Apart from the links i posted (one is from Nature) the main scaffolding to arrange what I write is Human-Evolution and Illustrated Introduction.
https://books.google.com/books?id=x...evolution an illustrated introduction&f=false

 

[sayak83]

Sure, the abiogenesis line of thinking, and everything spawned from that. This falls on it's face though when you ask the question of why we have both male and female counterparts of the species. Something had to produce asexually to start, think cell division or even a hammerhead shark. If you subscribe to evolution in it's entirety, then at what point did a male counterpart spawn and then a female counterpart? Was it in a single generation?

I get that we're examining MILLIONS of years, so it's surely possible. From a commonly accepted viewpoint of evolution, it doesn't seem to make sense why it would happen.

At its core sexual selection is not about males and females at all. You must remember that life remained unicellular for the first 3 billion years of its 4 billion year history, and properly speaking multicellular organisms are simply an odd and peripheral group that had decided to come together in a colony to access certain specialized ecosystems. Sexual reproduction arose first in unicellular eukaryotic cells and continued in them for 2 billion years before multicellular "colonies" began to be made by some of these eukaryotes. And of course in these single celled eukaryotic cells there is full blown sexual reproduction without any idea of male and female. Its just two fairly closely related cells merging together, sharing genetic information among themselves and then subdividing to create a set of "hybrid" cells. Why is this useful? Suppose the only way you reproduce is by cloning. Then the only beneficial mutations you have access to are what comes to you from your clonal line and you can never access the good genes and good mutations of your neighboring lines. This is not optimal. So what you do is "exchange notes" every so often so that you stay up-to-date with the best genes available in your neighborhood. This is logic of sex. Of course the world is a big place and there are living cells that are too distant and speak too different a language for the note exchange system to work. That is the reproductive or species barrier.

Now when the multicellular colonies of clones formed, they needed to create a coherent strategy to keep exchanging notes between other related colonies. So every so often the colonies would create cells that would "travel" from the two colonies, meet, mix and then quickly replicate lots of time to create a new colony made of the hybrid descendants. But many kept the option of just cloning new colonies (asexual reproduction is quite common in many plants and animals) when needed, not being picky of which colony "sends" and which colony receives (bisexual organisms, again a common thing in many plants and animals), while a few (basically those colonies where actually hitting on new colonies or bodies is quite frequent) have decided to specialize a bit on who sends and who receives. The small changes in the colony structure based on such specialization is what we call "male bodies" and "female bodies".

Cool?

Ever heard a "Ghost" recording? That static white noise they record and then claim (however true or not) to hear voices in it? What's interesting is how well adept the brain is at recognizing patterns. So let's say someone plays a recording for you. You hear noise. Then they say "Doesn't it sound like a voice is saying [whatever]?" They play it again and now you can make out those words in the noise. Now, once your brain hears that pattern, it cannot hear anything else in that pattern and will always recognize that pattern in the noise. It takes much retraining just to unlearn a simple voice in static noise!

Scientists are specifically trained to rule out false positives. You are talking about trained audio technicians here whose task and entire learning is to separate signal from the noise. I routinely find trace chemicals in air at parts per billion level through training and instrumentation. Such capability is the basic bread and butter for every scientist. We can always be better, but would you not heed my advice if I say your water has ppb levels of a poison or a micro-organism that makes it unsafe? Why do you not ask questions about how we could ever do this and not follow the advice then?

Which could very well be the answer we're looking for. Could be explained by a better hypothesis as well. A good question though is why we haven't found that "missing link."

There is no such thing and there can be no such thing. Every species is a transition between one past species and one future species. Think of it this way. Suppose you have a twin . Age they grow older and older one becomes an athelete and another a bookish academic. Now look at the picture of them when they were a month old baby. You can tell now from the retrospective lens who has become the athelete and who is the academic, but could you tell just from looking at the round plump toothless sleepy one month old faces. But move the photo forward and bring to junior school, high school, college etc. As the years pass, you see clues in their clothes and body that hint that they have chosen different paths. Think of the twins as adult as the modern species, and think of each ancestor species as their sequential photo in the yearbook back back back upto when they were newborn. Which one of those photos will be the missing link showing a muscular body and a nerdy spectacled face? None! Yet even today, being brothers they look similar and as you go back more and more, they look more and more similar until as 1 month old you can hardly distinguish them. The same is the case for species and their fossil lineages. I showed you one such case where 55 million years ago we have ancestors of lemurs and ancestor of tarsiers/monkeys/apes just beginning to look different from each other. I will show you more in later posts. That's evidence. There are lots like it.

One would assume that there should be plenty of evidence and remains to support this. There's not. What about the rock formations in South Africa around Adam's Calendar? There are no remains at all from the "people" who created all that. The lack of remains suggests some sort of intervention.

How atrociously absurd! These are stone settlements created by the Bokoni people, a sophisticated Iron Age civilization in Africa from about 1200-1600 CE that were wiped out by the coming of the Europians. First Europeans wipe out all the great urban civilizations in Africa by slave trading, then they forget they ever existed, and then they create such fanciful tales believing that Africans could never have been so "civilized"! Dear God.

http://mg.co.za/article/2015-02-26-the-bokoni-story-unearthed

There are two books that I would highly recommend to balance the Eurasia centric perspective of history many of us have (and lead to such crazy notions that aliens made those stuff in those other places as surely these savages couldn't could they?).

One is "Africa:Biography of a Continent".
And the other is 1491.

How old is the universe?

probably eternal, but the Big bang happened 13.8 billion years ago.

And we think nothing else could have interfered with our progression?

As soon as there is evidence. Basic fact, aliens coming from outerspace would make things out of steel, titanium or other exotic materials, not granite and stone like pre-industrial civilizations. People were as clever and as intelligent 6000 years ago as they are today, and their expertise in the materials they used then (stone) far exceed ours. Heck, I can't even make fire without a match or a lighter. And SETI and exoplanet search is actively looking for aliens. It would be great news if we do see that they have visited here before. But remember..false positives? Scientists are trained to detect false positives first and foremost.

The biblical timeline (i.e. been here 6000 years) is wrong, no doubt there (the Sphinx, Stonehenge, etc shatters that). But it's dangerous to automatically jump to the opposite. Our society is dividing everyone into two extremes. Creation vs. Evolution... I'm with the taco girl, why not both? Or maybe even neither, who's to know? Joining a side because there's only two is stupid (and this isn't directed at you). If given only two options, perhaps we start coming up with different options, because life is never that easy.

Groupism is nothing new. If its not that it will be football...

 

[idav]

A bit interesting that we've dug deep enough to find dinosaurs but have yet to find the remains of the "missing link." You'd think we find those before we got to dinosaur remains, no?

Thats like asking why we can only find puzzle pieces before being able to complete a puzzle. Really every fossil is a piece of the puzzle, every last one of the ape fossils tells part of the story, and apes certainly weren't around during dinosaurs, species don't just rise out of the ground fully formed.