Scott Klarr Jr

History and evidence for human evolution

Did humans evolve from apes or were we created as-is with a superiority to all other organisms? A good portion of the uneducated United States public reject evolution without fully understanding how it works, let alone being aware of the facts that back it up. This is truly sad because evolution is ONE of the MOST IMPORTANT scientific advances of understanding - EVER.

The processes that drive evolution are absolutely amazing and one can find great joy and wonder in understanding the realities of our past. I have gathered and made transcriptions of four videos that explain human evolution and provide some of the evidence behind it.

Video 1 - Human evolution animation by Carl Sagan.

Video 2 - Dr. Ken Miller on the fusion of human chromosome #2.

Video 3 - Human Evolution Made Easy by Youtube's Potholer54

Video 4 - Basic evidence for human evolution by friendofdarwin

Video 1 Transcription

Lets take a closer look at who our ancestors were. A simple chemical circumstance let to one of the great moments in the history of our planet. There were many kinds of molecules in the primordial soup. Some were attracted to water on one side, and repelled by it, on the other. This drove them together Into a tiny enclosed spherical shell like a soap bubble that protected the interior. Within the bubble, the ancestors of DNA found a home and the first cell arose. IT took hundreds of millions of years for tiny plants to evolve, giving off oxygen; but that branch didn't lead to us.

Bacteria that could breath oxygen took over a billion more years to evolve. From a naked nucleus, a cell developed with a nucleus inside. Some of these amoeba like forms lead eventually to plants; others produced colonies with inside and outside cells performing different functions becoming a pollock attached to the ocean floor filtering food from the water; and evolving little testicles to direct food into a primitive mouth. This humble ancestor of ours also lead to spiny skinned, armored animals with internal organs, including our cousin the starfish; but we don't come from starfish.

About 550 million years ago, filter feeders evolved gill slits which were more efficient at streaming food particles from the water. One evolutionary branch lead to acorn worms; another lead to a creature which swam freely in the larval stage but as an adult still anchored firmly to the ocean floor. Some became living hollow tubes, and others retained the larval forms throughout the life cycle and became free-swimming adults with something like a backbone. Our ancestors now, 500 million years ago were jawless filter feeding fish. A little like lamp rays. Gradually those tiny fish evolved eyes and jaws. Fish then began to eat one another; if you could swim fast, you'd survive. If you had jaws to eat with, you could now use your gills to breath oxygen in the water; this is the way modern fish arose.

During the summer, some swamps and lakes dried up, so some fish evolved a primitive lung to breath air until the rains came. Their brains were getting bigger. IF the rains didn't come, it was handy to be able to pull yourself along to the next swamp; that was a very important adaptation. The first amphibians evolved still with a fish-like tail. Amphibians, like fish, laid their eggs in water where they were easily eaten, but then a splendid new invention came along; Hard shelled egg, laid on the land where there were as yet no predators. Reptiles and turtles go back to those days. Many of the reptiles hatched on land never returned to those waters. Some became the dinosaurs. One line of dinosaurs developed feathers useful for short flights. Today, the only living descendants of the dinosaurs are the birds.

The great dinosaurs evolved along another branch, some were the largest flesh eaters ever to walk the land. 65 million years ago, they all mysteriously perished. Meanwhile, the forerunners of the dinosaurs were also evolving in a different direction: small, scurrying creatures with the young growing inside the mothers body. After the extinction of the dinosaurs, many different forms developed.

The young were very immature at birth in the marsupials, in the wombat for example, and in the mammals, the young had to be taught how to survive. The brain grew larger still. Something like the shrew was the ancestor of all the mammals.

One line, took to the trees, developing dexterity, stereo vision, larger brains and a curiosity about their environment. Some became baboons; but thats not the line to us. Apes and humans have a recent common ancestor. Bone for bone, muscle for muscle, molecule for molecule; theres almost no important differences between apes and humans.

Unlike the chimpanzee, our ancestors walked upright freeing their hands to poke and pick and experiment. We got smarter, we began to talk. Many collateral branches of the human family became extinct in the last few million years. We, with our brains and our hands, are the survivors. Theres an unbroken thread that stretches from those first cells to us.

Lets look at it again compressing 4 billion years of evolution into 40 seconds.

Video 2 Transcription

The second thing you saw at the trial was that data was introduced at the trial which I and another witness introduced from whole genome sequencing. The intelligent design advocates just literally nothing to say. We weren't asked questions in cross examination; the other side never brought it up, they never argued against it, but they just left it.

Heres an example. Many of you may know that a few months ago the genetic code of the chimpanzee was published. Therefor we can compare our genome to these primate relatives. What do we find? I want to show you one striking finding that dates to about a year ago. You all know that evolution argues that we share a common ancestor with the great apes; the chimpanzee, the gorilla, and the orangutan. IF thats true, there should be genetic similarities and in fact there are. But there is something that is really interesting that has the potential if it were true, to contradict evolution common ancestry. That is, we have two fewer chromosomes than the other great apes. We have 46 and all have 48. Thats very interesting.

What does that actually mean? Well first of all, The 46 chromosomes we have, you have 23 from mom and 23 from dad, so its actually 23 pairs. These guys have 24 from each parent so they have 24 pairs. Everybody in this room is missing a pair of chromosomes. Where did it go? Could it have gotten lost in our lineage? no. It a whole primate chromosome was lost, that would be lethal. So theres only two possibilities. That is, if these guys really share a common ancestor, that ancestor either had 48 chromosomes, or 46. Now, if it has 48, 24 pairs, which is probably true because three out of four have 48 chromosomes. What must have happened is that one pair of chromosomes must have gotten fused. So we should be able to look at our genome and discover that one of our chromosomes resulted from the fusion of two primate chromosomes. We should be able to look around our genome and you know what, if we dont find it, evolution is wrong and we don't share a common ancestor.

So how would we find it? Biologists in the room will know that chromosomes have nifty little markers. They have markers called centromeres that are dna sequences used to seperate them during mitosis and then they have cool little dna sequences on the end called telomeres.

What would happen if a pair of chromosomes got fused? Well, what would happen is the fusion would put telomeres where they don't belong in the center of the chromosome, and the resulting fused chromosome should actually have two centromeres. One of them might become inactivated but nonetheless they should still be there. So we can scan our genome and you know what, if we don't find that chromosome, evolutions in trouble.

Well, guess what: Its chromosome number two. Our chromosome number two was formed by the fusion of two primate chromosomes. This was the paper from nature, a little more then a year ago. I put up a little bit of the paper and I'm sorry its technical, but look at what it says: chromosome two is unique to our lineage. it emerged as a result of a head-to-head fusion of two chromosomes that were made separate in other primates.

Those of you who have not kept up with how much we know about the genome should pay attention to this because you'll be amazed at how precisely we can look at things. The precise fusion site has been located base number 114,455,823-114,455,838 so in other words within 15 bases. You'll notice in multiple subtelomeric duplications; the subtelomeres that don't belong and low and behold, the cetromere that is inactivated corresponds to chimp chromosome number 13.

Its there, its testable, it confirms the prediction of evolution. How would intelligent design explain this? Only one way, by shrugging and saying thats the way the designer made it. No reason, no rhyme; presumably there is a designer who designed human chromosome number 2 to make it look "as if" it were formed by the fusion of a primate ancestor. I'm a roman catholic, I'm a theist in the broadest sense. I would say I believe in a designer but you know I don't believe in a deceptive one. I don't believe in one who would do this to try and fool us, and therefore I think this is authentic and it tells us something about our ancestors.

Video 3 Transcription

In previous videos I've shown evidence how the world around us was formed. but the fundamental question remains, how did we get here?

The void is always been filled by fantasiful stories. The Chinese believed that a dragon goddess wanted someone to talk to so she formed humans out of clay from a river bank. According to Jewish mythology, the god made man out of clay and fashioned a woman out of one of his ribs. Inuit mythology describes a raven god who filled the earth with pea pods and one of these burst open to reveal the first man. But 150 years ago one book shattered these myths and opened the door to a rational and evidence based understanding of our origins.

But while Charles Darwin and Alfred Wallace jointly came up with the idea of natural selection, they parted company on rather this evolutionary mechanism could be applied to humans. Wallace formulated the idea that animals could have evolved but he couldn't compromise his belief that humans were the work of a deity. Darwin came to the inevitable conclusion and called it my little heresy.

The little heresy was not first expounded by Darwin but by naturalist Thomas Huxley in an 1863 book called "evidences to mans place in nature." Huxley and his supporters had clear that evidence in evolution in animals; what they lacked was direct physical evidence to show that evolution also applied to humans.

The search was on for what is now known as the missing link. A fossil that was half human and half ape. We of course are all apes according to classification, but for the purpose of simplification, I will refer to human apes and humans, and our common ancestor with chimpanzees apes.

It didn't take long for this new branch of science to find its first piece of evidence. Just three years before Darwin published the origin of species, The bones of what looked like an oddly formed human unearthed in the Neander valley in Germany. Neanderthal man was not the missing link but did seem to be one of our archaic ancestors. In 1891 fossil bones from the first real archaic hominid called homo erectus were found on Java island. 32 years later, another Homo erectus skull "peeking man" was found in china. Neither of these fossils were the fabled missing link; they were closer to humans than to apes. But they did spark the idea that humans may have evolved in Asia. Africa was also beginning to yeild some valuable finds including the "Taung child" found in south africa in 1934. The problem was, these didn't fit with another discovery made 16 years earlier in southern england: "piltdown man."

But as more fossils emerged from south Africa in the 1930s, it became clear that piltdown man was the anomaly, not the Taung child. Piltdown man just didn't make any sense, either in its physiology nor in its geographic location. It only made sense in 1953 when the hoax was revealed. By then the distribution of hominid fossils had given rise to two schools of thought on human origins. An African origin, and a multi-regional origin - The idea that humans originated from archais hominids in different parts of the world. But over the next 40 years, paleo anthropologist uncovered the motherload of hominid fossils. [series of fossil images in video]

The idea of a missing link has long been relegated to the status of a quaint 19th century pre-occupation. Finding fossils that link humans to ancestral apes isn't the problem. The problem is that east Africa has produced so many of them that paleoanthrologists are having a hard time sorting out which are our direct ancestors and which are the evolutionary dead ends. We find what we find in most animal species, a wealth of relatives. Some of them branched off and reached a dead end quickly. Others evolved hundreds of thousands of years before becoming extinct. So our family tree turns out to be very rich indeed. Its kind of like trying to find the next of kind of an orphaned baby and coming with not only direct ancestors, but also their brothers, sisters, uncles and cousins. But together these hominid fossils tell a single story. As we work our way forward in time, just as expected, they become less and less ape like and more human like.

Believers of an instant creation have a couple explanations for this wealth of fossil evidence.

1. "fake fake fake fake" yeah, Ive heard that from a few conspiracy theorists, but even creationist organizations aren't suggesting anything so absurd.

2. "these are all just fossils of apes." Well, nobody disputes that! but what species of ape? Theres clear evidence that some of these apes could light fires and make tool and hunt with weapons. They walked on two legs, but they weren't human either. They had obvious ape characteristics like arms longer than legs. What were they all doing in the garden of eden? And why do we see a clear progression through time of ape-like creatures disappearing and more intelligent and more human like species appearing in the sedimentary layers above?We never see a species disappearing to be replaced by something less intelligent and less human-like.

3. "Some of the skulls have been wrongfully assembled." That might be true in some cases, but not in all. Skull shape is only one characteristic that separated humans from apes. A more slender body form, a larger brain size, walking on two legs, opposable thumbs; these are all crucial human features we see evolving gradually through time. Evolution from ape characteristics to human characteristics can also be found in the smallest details. From the shape of the pelvis to the thickness of tooth enamel.

When the field of DNA opened up, paleoanthropology got its first big break. This completely new field of science would either confirm one of the accounts of our mythical creation or it would confirm the evidence of slow evolution. Guess which one turned out to be right.

Genetic evidence is consistent with evolution from apes. or is it? When geneticists investigated, they discovered that humans only have 46 chromosomes and all the other great apes have 48. So we couldn't have evolved from a common ape ancestor... Unless, two of the chromosomes could have fused. well theres only one way to find out, Ill let Dr. ken miller pick up the story. ""So we can scan our genome and you know what, if we don't find that chromosome, evolutions in trouble. Well, guess what: Its chromosome number two."

DNA finds our common ape ancestor

Mitochondrial DNA (mtDNA) tells us even more. It shows that out nearest relative in the animal kingdom is exactly as the fossil evidence predicted. The great ape, the chimpanzee. And when did we last share a common ancestor? Around 5 million years ago, just before the date of the first ancestral hominid fossils!

Neanderthal mtDNA analyzed

Mitochondrial DNA from a Neanderthal fossil has also been analyzed and its completely different from every type of modern human. It shows that humans and Neanderthals last shared a common ancestor around half a million years ago.

mtDNA finds our common human ancestor

Mitochondrial DNA can only be passed from mother to child. It mutates at a fairly regular rate. Lets say this womans mtDNA develops a mutation, lets mark it red. The kids will share the same mutation, but only the girls will pass it on. Several generations later, another part of the mtDNA mutates, lets give this one a blue coat. Then another one mutates, a green coat. Then more mutate. Thousands of generations later we can see a clear pattern. Closely related people share a lot of common mutation markers. The less closely related they are, the fewer common mutations they share. But everyone shares the red mutation which means they can all be traced back to a common female ancestor. Since geneticists know roughly the rate in which these mutation occur, they can work out when and where she lived. The results coincided perfectly with the fossil evidence- around 150,000 years ago in Africa.

She wasn't the only woman around at the time of course, we have ancestors going much further back in time but she is our most recent common ancestor.

Ive laid out the twists and turns of the last 150 years because science doesn't move in a straight line. Ideas are constantly being refined, updated and amended as more evidence comes to light. There are no forgone conclusions and no preconceptions; instead, we feel our way into a darkened room, collecting evidence and getting closer and closer to an understanding of the layout.

When DNA analysis came along it was as if a light has been switched on. Almost nothing in the DNA evidence contradicts what we find in the fossil evidence. Together they give us the broad picture of our origins.

Video 4 Transcription

Creationists will have you believe that human beings are the result of 'special creation' by God. In reality human being, like all other life on earth, evolved from ancestral species. In this video, I will demonstrate why this is true.

There are four pieces of evidence for our ancestry:

1. Relation to living primates
2. Vestigial structures
3. The fossil record
4. Genetics

Evolution is the ONLY way to logically explain these pieces of evidence.

Its obvious that we share our basic anatomical structure with apes. These similarities are not superficial. Here are just a few common traits that all primates share:

1. Forward facing eyes
2. Grasping hands
3. Relatively large brains
4. Dental structure

Humans have a distinctive 2123 dental formula: 2 incisors, 1 canine, 2 premolars and 3 molars. The same as all old-world monkeys and all apes. This is no coincidence. Compare the ape formula with that of an opossum: 2123 vs 5134 (top jaw) and 4134 (bottom jaw). Mammal dentition is extremely varied. Any biologist, taxonomist or paleontologist will tell you that a mammal's teeth are worth a thousand words. Human beings and other primates look and behave similar as well.

Did you ever wonder why you have an appendix? The appendix is a vestigial structure that was once used for digesting cellulose in our largely vegetarian ancestors.

Wisdom teeth? They were used to help grind up tough plant matter before our diets changed and our jaws shrunk accordingly. Tailbone? Body hair? Goosebumps? Thirteenth rib? Yup, evolution is responsible.

The hominid fossil record is: hideously incomplete, fragmentary, and widely debated.. but still an extremely reliable piece of evidence for our ancestry. Although controversy is ripe within paleoanthropology, there is no dispute over whether ancestral hominid fossils exist.

Despite being very incomplete, we will have a wealth of hominid fossils. Just have a look [3:42 series pictures shown in video]. Hominid fossils are indisputable, hard evidence that ancestral hominids existed - period.

Remember the dental formula for our primate relatives? The jaws and teeth of our ancestors demonstrate a clear transition between ape jaws and ours. [4:26 series of pictures shown of Chimpanzee jaw, Australopithecus jaw, Homo erectus jaw, Homo sapien jaw ].

The fossil record shows a hominid tree of life, not a linear progression. How a creationist can argue against evidence you can literally hold in your hand is truly perplexing.

Himans share 98% of our DNA with Chimpanzees. That is a higher percentage than zebras share with horses or than one species of mice shares with another of the same genus. So why do we assume we're different? Awfully arrogant, isn't it?

Geneticists have estimated when the chump and human lineages separated by measuring the differences in our genes. Guess what! The estimate matches the date when the early hominids first appear in the fossil record. How can creationists explain all of this evidence without evolution? They cant. Creationists ignore all evidence for human evolution because it threatens their worldview. its time to wake up creationists - we evolved!