There are multiple lines of evidence that indicates that humans share a common ancestor with the other ape species alive today. I wish to look at some of these lines from genetics.
Often, OE vs YE discussions of genetics descends into an endless discussion of whether the genetic similarity between the many species is due to a common designer or due to common descent. I have issues with why YEers think that a common designer is an adequate explanation once you get away from whatever definiton of "kind" they chose (or not chose usually) to give. But, in the end, those discussions are usually fruitless because there is a convenient out even if calls for evidence are generally lacking.
Instead, I prefer to delve into areas where similar form is no longer expected to yield similar genetics. Some of these still involve coding genes. For exampe cytochrome C seems to work in a myriad of forms, can be successfully transferred across widely varying species, and yet still follows a pattern consistent with common descent. There have been a few other such areas that have been touched upon recently on the sidelines of other threads and I thought it might be useful to bring them into their own thread.
Now this is going to take the form of things such as pseudogenes and retroviral insertions that are non-coding. The most common objection raised is that we might not always know that the gene in question does not actually play a role. And for most of these cases, you can even present a few examples of cases where function has been found for such. For example, in a recent thread on whether new information can arise I gave an example of humans acquring a new gene through a retroviral insertion that proved to be useful. Some pseudogenes have been found to actually have functions. But the key is to not let the few outliers fool us. Giving a use for one or two pseudogenes does not mean that they all have a function.
And often, we can know that they do not have a function. I'll use this as a lead in to my first example: pseudogenes. Most animals make vitamin C through a series of four enzymes. Both humans and the other primates are unable to do this. They all share a very specific mutation in the same gene. This is an example of where we can compare the function of a gene directly in other animals and se that the function has been lost and what mutation caused it to be lost.
My first reference.
"Genomic divergences between humans and other hominoids and the effective population size of the common ancestor of humans and chimpanzees," Chen FC, Li WH, American Journal Human Genetics, 2001 Feb;68(2):444-56.
I want to look at pseudogenes can be used to trace the evolutionary history of apes. For this paper, they used "53 autosomal intergenic nonrepetitive DNA segments from the human genome and sequenced them in a human, a chimpanzee, a gorilla, and an orangutan." These segments included "Y-linked noncoding regions, pseudogenes, autosomal intergenic regions, X-linked noncoding regions, synonymous sites, introns, and nonsynonymous sites."
When all the various sequences are considered as togther, they "supports the Homo-Pan clade with a 100% bootstrap value." This is pretty clear evidence of the shared common ancestor for humans and chimpanzees.
So, at least for this one analysis, the common ancestor of the chimps and humans is almost certain.
Often, OE vs YE discussions of genetics descends into an endless discussion of whether the genetic similarity between the many species is due to a common designer or due to common descent. I have issues with why YEers think that a common designer is an adequate explanation once you get away from whatever definiton of "kind" they chose (or not chose usually) to give. But, in the end, those discussions are usually fruitless because there is a convenient out even if calls for evidence are generally lacking.
Instead, I prefer to delve into areas where similar form is no longer expected to yield similar genetics. Some of these still involve coding genes. For exampe cytochrome C seems to work in a myriad of forms, can be successfully transferred across widely varying species, and yet still follows a pattern consistent with common descent. There have been a few other such areas that have been touched upon recently on the sidelines of other threads and I thought it might be useful to bring them into their own thread.
Now this is going to take the form of things such as pseudogenes and retroviral insertions that are non-coding. The most common objection raised is that we might not always know that the gene in question does not actually play a role. And for most of these cases, you can even present a few examples of cases where function has been found for such. For example, in a recent thread on whether new information can arise I gave an example of humans acquring a new gene through a retroviral insertion that proved to be useful. Some pseudogenes have been found to actually have functions. But the key is to not let the few outliers fool us. Giving a use for one or two pseudogenes does not mean that they all have a function.
And often, we can know that they do not have a function. I'll use this as a lead in to my first example: pseudogenes. Most animals make vitamin C through a series of four enzymes. Both humans and the other primates are unable to do this. They all share a very specific mutation in the same gene. This is an example of where we can compare the function of a gene directly in other animals and se that the function has been lost and what mutation caused it to be lost.
My first reference.
"Genomic divergences between humans and other hominoids and the effective population size of the common ancestor of humans and chimpanzees," Chen FC, Li WH, American Journal Human Genetics, 2001 Feb;68(2):444-56.
I want to look at pseudogenes can be used to trace the evolutionary history of apes. For this paper, they used "53 autosomal intergenic nonrepetitive DNA segments from the human genome and sequenced them in a human, a chimpanzee, a gorilla, and an orangutan." These segments included "Y-linked noncoding regions, pseudogenes, autosomal intergenic regions, X-linked noncoding regions, synonymous sites, introns, and nonsynonymous sites."
When all the various sequences are considered as togther, they "supports the Homo-Pan clade with a 100% bootstrap value." This is pretty clear evidence of the shared common ancestor for humans and chimpanzees.
So, at least for this one analysis, the common ancestor of the chimps and humans is almost certain.