Differences between human and ape

[Glee]

Hey all. So what exactly are the differences between a human and an ape? By reducing each difference down to their component level, why is it considered by some that it is just not possible for humans to have evolved from them? What individual change cannot be the product of 'microevolution', and when does it change to 'macroevolution'?


I shall use the dog as an example for microevolution in some cases, as they all developed from the same 'kind' via 'micro'...

For example:

Skeletal structure? - The number of bones is almost identical at certain stages of development. The lengthening of certain bones and fusing of others really isn't that much of a jump to make in terms of microevolution. If a jack russel and a great dane evolved from the same animal via microevolution, how is this change any different? Same goes for size.

Skull shape? (tied in with skeletal structures)- The difference between a greyhound and a bulldog?

Hair? Really, there are a lot of really hairy people out there, and some that have no hair at all. Is it that far a strectch to image a minor genetic change that reduced the amount, or that once some ansector was that hairy?

Intelligence? See http://www.medicalnewstoday.com/medical ... wsid=31235 - most of the difference in intellignece are because of different levels of hormones in the body. The hormones are all there, just different quanitites regulate the size of growth and brain development. We have many genetic conditions today which create different levels of hormones which influence intelligence, growth and development within humans already today. Is there really that much of a difference?


Is there any single change which is not possible between the two? Where is the line drawn for microevolution?

[Cathar1950]

Maybe the line is really arbitrary. It is a convention. Our human qualities alow us to share these things and is most likely a product of adaptation that has worked for us. At least so far. I suppose there maybe some legitimate doubt as to it's future value. I was watching the National Geographic Channel this morning on clever birds. Ants kind of look stupid on their own if you look at the individual ant but together they got something going. Look at the dung termite opening and closing little doors to keep the dung heap the same temperature. Cool stuff.

[QED]

Gorillas are incredibly "human". They like a bit of peace and quiet too. Our family visited Longleat Safari Park earlier this year and they have a place called Gorilla Island. In the middle of a lake is said Island populated by Gorillas who have their own house complete with satellite TV! Apparently gorillas see in full colour and their favourite programmes are Scooby Doo and the Tweenies! It's so amusing to see an 'animal enclosure' with its own satellite dish

[jcrawford]

Hey all. So what exactly are the differences between a human and an ape? By reducing each difference down to their component level, why is it considered by some that it is just not possible for humans to have evolved from them? What individual change cannot be the product of 'microevolution', and when does it change to 'macroevolution'?

I shall use the dog as an example for microevolution in some cases, as they all developed from the same 'kind' via 'micro'...

For example: Skeletal structure? - The number of bones is almost identical at certain stages of development. The lengthening of certain bones and fusing of others really isn't that much of a jump to make in terms of microevolution. If a jack russel and a great dane evolved from the same animal via microevolution, how is this change any different? Same goes for size.

Skull shape? (tied in with skeletal structures)- The difference between a greyhound and a bulldog?

Hair? Really, there are a lot of really hairy people out there, and some that have no hair at all. Is it that far a strectch to image a minor genetic change that reduced the amount, or that once some ansector was that hairy?

Is there any single change which is not possible between the two? Where is the line drawn for microevolution?

The details of dog evolution notwithstanding, the human problem of going into the details of human evolution out of Africa require us to imagine a very gradual step by step process of non-human primates of some sort being slowly transformed into human beings like ourselves over several million years or so.

Let's start with a chimpanzee like Lucy. She was considered to be a superior candidate for human ancestry only 20-30 years ago by the Leakeys, even though australopithicine apes are no longer considered contenders for that ancestral distinction by most neo-Darwinist paleoanthropologists today.

Now, chimpanzees average 3 feet in height, swing from trees or hobble along on all fours when not reaching up for higher branches or bananas.

http://www.janegoodall.ca/chimps/chimps_behav_phys.html

From the professional data provided thus far, let us begin to imagine what physical and morphological mutations would have to occur in order for chimp-like non-human primates in Africa to gradually start looking a little more human over a period of several million years.

We obviously have a lot of evolutionary time in which to imaginatively accomplish this super neo-Darwinist feat of a non-human African primate evolving into a full human being in Africa, so let's start with any part of the chimpanzee which you feel is in need of some tissue modification and skeletal reconstruction in order to start looking a little more human.

Those of you who feel especially qualified to demonstrate neo-Darwinist evolution in action may go first if you like while the rest of us scratch our human heads for some evolutionary inspiration regarding gradual genetic mutations which allow some creatures to environmentally adapt and survive while others gradually or eventually become extinct.

[Glee]

The details of dog evolution notwithstanding, the human problem of going into the details of human evolution out of Africa require us to imagine a very gradual step by step process of non-human primates of some sort being slowly transformed into human beings like ourselves over several million years or so.

Let's start with a chimpanzee like Lucy. She was considered to be a superior candidate for human ancestry only 20-30 years ago by the Leakeys, even though australopithicine apes are no longer considered contenders for that ancestral distinction by most neo-Darwinist paleoanthropologists today.

Now, chimpanzees average 3 feet in height, swing from trees or hobble along on all fours when not reaching up for higher branches or bananas.

http://www.janegoodall.ca/chimps/chimps_behav_phys.html

From the professional data provided thus far, let us begin to imagine what physical and morphological mutations would have to occur in order for chimp-like non-human primates in Africa to gradually start looking a little more human over a period of several million years.

We obviously have a lot of evolutionary time in which to imaginatively accomplish this super neo-Darwinist feat of a non-human African primate evolving into a full human being in Africa, so let's start with any part of the chimpanzee which you feel is in need of some tissue modification and skeletal reconstruction in order to start looking a little more human.

Those of you who feel especially qualified to demonstrate neo-Darwinist evolution in action may go first if you like while the rest of us scratch our human heads for some evolutionary inspiration regarding gradual genetic mutations which allow some creatures to environmentally adapt and survive while others gradually or eventually become extinct.

From your site:: "Chimpanzees can also walk upright (on two legs in the bipedal position), when carrying something in their hands or when looking over tall grass." This seems to fit in with evolution's model that groups of hominidae moved from the forests to the plains (or forced, if climate change resulted in the death of forests in that area) where standing on hind legs allowed them to spot both predators and prey with much more ease.

I'm having trouble finding any decent comparisons of chimpanzee and human anatomy at all - there are lots of sites out there with generalised knowledge, but few that site anything worth being that reputable. I have found none that decisively says with any credibility anything about the internal organs of chimps in comparision either.

Probably the best I have come across is http://uts.cc.utexas.edu/~bramblet/ant301/seven.html , which is taken from the "Department of Department of Anthropology, College of Liberal Arts , UT Austin". They state at the top of each page that "These pages are in development and will contain errors" though, it is the most comprehensive comparison I have found. No pictures though.

It lists skeletal differences between humans and chimpanzees. With teeth, for instance, it describes how the canine teeth in chimps are much larger, robust, and project far above their tooth row. Trivial differences such as the relative size of teeth are negliable, right? One could see how a change in diet over centuries could lead to certain teeth being less useful, etc.

The big differences in relation to skeletal structure seem to be ::

Human skull capacity: On average, 1,201cm^3 for humans, while only 400 cm^3 for chimps. I believe the site i quoted in the original post was evidence of how this could have happened.

Vertebral Column and Thorax: Chimps usually have one more thoratic vetebrae and one more set of ribs to match this extra vertebrae. Humans have 12 paired ribs while chimps have 13. Is this a mere coincidence? Don't know exactly how it happened... prehaps it's like how some children are born with 6 fingers, occasionally people are born with 1 rib less or more. The article does seem to imply the the exact number of vertebrae is variable by +/-1 in both humans and chimps.

Arms and legs, hands and feet: Fairly obvious visaul differences just from the appearance, but there are no extra bones in these limbs. Mucsles are much more under and over developed in each species - Human arms are comparitively much weaker and shorter, while the legs are much longer and stronger.

I have a passing knowlegde of how evolution is supposed to explain the change in limbs, however I would prefer to leave that to someone who knows their stuff better than I.



As an aside, because this site has no credibility whatsoever as far as i know, http://personal.uncc.edu/jmarks/interes ... saaa99.htm raises some interesting ideas. The 98.6% match between human and chimpazee DNA is quoted alongside the suggested 33% match between human and daffodil, as a prompt about how DNA comparisons work- that being there are only 4 bases in DNA. Take from that what you will. Also, they mention that "since humans are tetrapods, it means that humans fall into that paraphyletic category we call fish. In other words, we are phylogenetically apes, but only in precisely the same sense that we are phylogenetically fish." They have a cute little picture to match it too. Apart form that it is just a general history of the attempts to compare via DNA and amino acids the similarity of humans and apes.

(personally i find the number of ribs issue to be very interesting, and am putting more thought into that matter...)

Edit: Fixed link

[jcrawford]

From your site:: "Chimpanzees can also walk upright (on two legs in the bipedal position), when carrying something in their hands or when looking over tall grass." This seems to fit in with evolution's model that groups of hominidae moved from the forests to the plains (or forced, if climate change resulted in the death of forests in that area) where standing on hind legs allowed them to spot both predators and prey with much more ease.

Habitual bipedalism seems a good place to start with our chimp transition into the first human 'species' in Africa, assuming that the emergence of Homo habilis eventually led to the full habitual bipedalism of Homo erectus or ergaster in Africa.

So we have some chimps standing on hind legs from time to time which
allows them to "look over tall grass and spot both predators and prey with much more ease." The chimps have no choice but to be out in the grasslands because some unknown and unexplainable climate change has caused all the trees in the forest or jungle for miles around to die. Under those conditions, I would imagine that thousands upon thousands of chimps would be out on the grasslands having being deprived of their ancestral trees.

In trying to adapt to their new environment on the grasslands, after the catastophic climate change, and the absence of trees, some chimps would manage to catch more prey and avoid more predators than other chimps by being able to stand on their hind legs in the tall grass for longer periods than other chimps and subsequently developed stronger, longer and faster hind legs. At the same time, not having to swing from trees any longer, their arms eventually got shorter through disuse on the ground, and all these physical limb changes were passed on to their descendents as new generations of grassland chimps came into existance.

Now, I'm not sure if these shorter armed, longer, stronger legged chimps are starting to resemble the first people on earth in Africa at his point, because nothing else in the environment seems to be cause for any other physical changes in the chimps. Maybe someone with a little more knowledge about how chimps could evolve into more human-looking African people could take it from here and show us how natural forces could cause other bodily and facial features of chimps could gradually look a little less ape-like.

[Glee]

Ice ages, etc may caused dramatic climate change, and we know that certain trees only grow in particular envrionments. If the envrionment changes, then this may eventually lead to deforestation, or the forest at least lacking the abundance of fruit and food the animals need to survive. Alternatively, forest fires, overpopulation, a lack of food, or an abundance of predators may have also driven groups of hominidae out into the plains as an alternative home.

Environmental influences would not have been the only driving factor to the eventual outcome, although deforestation may not have been the only reason.

Much of it may have been to do with breeding and courtship rituals - Because the fastest runner, the smartest, the most co-ordinated with using their hands, would most likely have been the leader of the group, or potentially, the largest and strongest of the group would have had priority in who mated with whom. Or maybe each of these features at one stage or another was the determining factor, creating an effect similar to that of peacocks, where an almost useless but decorative plume has evolved to attract mates.

If only the 'chimps' that are stronger/taller/faster/smarter are breeding, then the genes that have been beneficial in these regards will be passed down the line, while those chimps that don't have these beneficial mutations will not continue to pass on their genes.

There is also the idea that only the stronger/taller/faster/smarter survived, for without these attributes, similar to a herd of deer, the slowest/lame/unprepared will be the ones picked off by predators first.

Opinion/idea, not fact: One last feature that might also have played a role is that of genetic diseases, such as the one Robert Pershing Wadlow suffered from. http://en.wikipedia.org/wiki/Robert_Pershing_Wadlow or http://en.wikipedia.org/wiki/Gigantism for reference... something that may have been a 'disease' may have actually accelerated the growth in a paticular group tremendously, which, if the geneology were passed on, all future generations of that group may have that trait. Gigantism may lead to death at a somewhat early age, but it would have been enough time to mate and pass on the genes, if they were accepted by their group and not outcast. And eventually, there may have been some mutation which allowed for a normal or longer lifespan, such as a larger or stronger heart, or an improved circulatory system. Who says the changes have to be one small step at a time?

Then again, we know that diet and the health of the person affect the average height as well, and if the diet and lifestyle had changed dramatically, then there may be, after a few generations, quite a change in height naturally. See http://en.wikipedia.org/wiki/Human_height for more about that...

[Glee]

Facial features
I believe the commonly accepted idea for creation/ID microevolution is to allow for a wolf like dog to become a great dane, a jack russel, and everything in between. This is done so Noah can fit all 'types' of creatures into the ark.

So if this principle is accepted, i present the bulldog and the greyhound.

Bulldog: http://www.boneclones.com/BC-128.htm

Greyhound: http://www.skullsite.co.uk/Grhnd/grhnd.htm

Both came from the same 'type', yet the skulls are dramatically different.

The changes in both shape and size of the skull, and dental features of these animals is far less different to that of a human and a chimp.

Possible?

Chimp: http://www.talkorigins.org/faqs/homs/chimp.html

Human: http://www.gwc.maricopa.edu/class/bio20 ... atskul.htm

Time
It should probably be right to delve into time periods of which this all happened.

http://anthro.palomar.edu/earlyprimates ... _Earth.htm - Primates first appeared in the Cenozoic era, which started around 65 million years ago. The apes and monkeys evolved to some level from 35 million to 23 million years ago. 'Near human' species were present from roughly 5 million years ago. So a reasonable time frame for this evolution (ape to humanlike) to happen would be around 18 million years.

According to creationist population growth mathematics, 4000 years is enough time for a population of humans to grow from 8 to 6 billion. (8 - 6,000,000,000 - just to see it expanded) Exponential growth of apelike species, with faster brithrates, earlier sexual maturity but lower expected life expectency would probably result in a similar growth pattern...

So over 18 million years, there would be a lot of apes born. The diversity in size and shape amongst humans is fairly well documented over their small time scale of existence, so it can be assumed that in 18 mil there will be some diversity in the size of hominidae? Considering the change from the greyhound-to-bulldog skull can happen within 4000 years, could the changes in the chimp-to-human happen within 18 million?

[USIncognito]

I shall use the dog as an example for microevolution in some cases, as they all developed from the same 'kind' via 'micro'...

For example:

Carnack holds the envelope to his turban - "What is pi** and vinigar?" The open envelope reads - Name two things Glee is likely to analogize in the future based on the logic of this post.

Skeletal structure? - The number of bones is almost identical at certain stages of development. The lengthening of certain bones and fusing of others really isn't that much of a jump to make in terms of microevolution. If a jack russel and a great dane evolved from the same animal via microevolution, how is this change any different? Same goes for size.

Well, your whole premise is faulty since we know that all dogs are the same species effected by human selection, but we don't find some dogs with curved spines and others with straight ones. We don't find some dogs with splayed knees, but linear shoulders but others not, as we do with chimps and humans. And don't find virtually identical carpal structure, but different tarsal structure in dogs like we do with humans and chimps. Oh, and there's a very important skeletal structure, but since you're trying to get to much mileage out of this issue....

Skull shape? (tied in with skeletal structures)- The difference between a greyhound and a bulldog?

Oooo! It was almost painful to read this. Do you know what the Foramen Magnum is? I'm assuming you don't since it eviscerates your argument. It's the hole at the base of the skull that allows the brain stem to connect with the spinal collumn. In quadrapeds, it's always posterior, but in bipeds, it's ventral. (Keep in mind a biped ventral is it's feet, not it's frontside) In Chimpanzees the Foramen Magnum is mostly posterior, but in each of the skulls we find of Australipiticus and Homo species we find, it moves progressively to the ventral.

Such a progression is exactly what we'd expect from evolution and common ancestry.

Hair? Really, there are a lot of really hairy people out there, and some that have no hair at all. Is it that far a strectch to image a minor genetic change that reduced the amount, or that once some ansector was that hairy?

This is rediculous. By this logic, since whales, manatees and rhinos are as comparatively hairless as humans, they were either specially created or are not mammals since one of the phylogenetic parts of being mammal is being covered with hair. And humans are covered with hair despite what Playboy would have us believe. Well, except for around our eyes (excluding eyebrows) on our palms and feet... just like chimpanzees.

Your intelligence objection isn't worth consideration because giving a Stanford-Binet to a Frenchman, New Guinea highlander or Honduran Mayan is about as worthless as applying human intelligence standards to a Chimp, Gorilla, Orang, Gibbon, Dolphin, Bandicoot or Rat. There are definate analogies to be drawn, but unless we can really communicate with these species in their language, we really have no idea about their level of intelligence.

On a contrarian note. I finished reading "What it means to be 98% Chimpanzee" by Jonathan Marks a few weeks ago and while I found a lot of his points maddening, he does make some great ones about approaching the issue of evolution from the standpoint of his specialty - molecular anthropology.
(for the record, he does support the neo-Darwin synthesis, but he calls a lot of assumptions on the carpet)

[USIncognito]

Time

According to creationist population growth mathematics, 4000 years is enough time for a population of humans to grow from 8 to 6 billion. (8 - 6,000,000,000 - just to see it expanded) Exponential growth of apelike species, with faster brithrates, earlier sexual maturity but lower expected life expectency would probably result in a similar growth pattern...

Umm, yeah, except that Creationist "population growth mathematics" (is that different from regular mathematics?) would have there being about 1,000 people to populate the entire Earth and maybe a few dozen of them to build the Pyramids, and only several hundred thousand humans in existance when we know Rome alone had a population of 1,000,000. Exponential extrapoloations work great in theory, but tend to fail in real life.