Additional Support for Out of Africa

As I understand it, there are two main competing models for the origin of modern humans. As Science News puts it:

The origin of modern humans is a debated topic. One leading theory postulates that the ancestors of all modern humans originated in East Africa and then left the continent around 100,000 years ago. From there, they colonized the world, displacing previously established hominids such as Neanderthals in Europe. The best evidence so far for this theory is the higher genetic diversity (and thus inferred older age) of the African population compared to populations from other continents.

A minority theory proposes that modern humans evolved simultaneously in different regions of the world from populations of archaic humans and that both contributed to the current human genetic pool. The modern Homo sapiens species is, therefore, seen as the result of the sharing of genes and behaviors between archaic and modern humans.

For more information see this.

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A new paper has been published that supports the leading model. Here is the abstract:

A leading theory for the origin of modern humans, the ‘recent African origin’ (RAO) model, postulates that the ancestors of all modern humans originated in East Africa and that, around 100,000 years ago, some modern humans left the African continent and subsequently colonised the entire world, displacing previously established human species such as Neanderthals in Europe. This scenario is supported by the observation that human populations from Africa are genetically the most diverse and that the genetic diversity of non-African populations is negatively correlated with their genetic differentiation towards populations from Africa.

Using a dataset of 377 autosomal microsatellite loci from 51 populations, the authors looked at the correlation between genetic diversity and geographical distance from Ethiopia, where the oldest human remains have been found. They found a pretty smooth negative correlation between the two. That is, the farther away the population sampled was from Ethiopia, the less genetic diversity was found.

Now this certainly is not my field and I am not qualified to critique the paper, but it does seem to support the leading model. Also in the news summary one of the authors says, "The lack of stark differences suggests that humans cannot be classified in discrete ethnic groups or races on a genetic basis."

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A Different Kind of Blog

Jeffery of Issues in Mormon Doctrine and I have launched a new blog called Mormons and Evolution. Before you get all bent out of shape about another blog in the bloggernacle, let me explain. The scope of the new blog is intended to be very narrow. I anticipate that it will not move as quickly as most other blogs because we are trying to be more methodical and thoughtful.

I anticipate that many of my posts there will be cross-posted here, but I plan on maintaining a broader scope here.

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A Chromosomal Argument with Strings Attached

Over at Times and Seasons they're talking about the conception of Jesus and whether it was sexually-based as some of the early brethren seemed to think it was. I have not had a strong opinion one way or another--I'm not creeped out either way.

In order to support the doctrine that Jesus is literally the Son of God, however, some (Stephen Robinson comes to mind) have argued that Jesus had 46 chromosomes--23 from each parent. I used to think this was a pretty persuasive argument, but now I'm not so sure.


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Enter Evolution: (Always with the evolution!) Our genomes seem to have been shaped by somewhat random forces. In terms of organization and sequence they appear to be quite similar to other primates, especially chimpanzees. Not only are they similar, but there are clues that allow us to infer common ancestry. One change that has occurred in humans since the split from chimpanzees is that two chromosomes in the common ancestor fused to form our chromosome #2. (For a little more on this subject see here.) I don't know if a successful human-chimpanzee hybrid could be produced, but I doubt it. The difference in chromosome number would cause problems. There is a certain point where chromosomal abnormalities lead to cell death.

What I'm saying is that there may be no reason to assume that if God has DNA, that he has 46 chromosomes. Now if you assume that Adam was literally the offspring of God then the chromosomal structure would match up, I suppose, but then we have to explain why other primates have DNA so similar to ours. Not only similar, but as I said, with evidence that suggests a directionality of change opposite of what we would expect under this assumption.

This leaves several possible senerios:

1. On the divine side, no DNA was involved.
2. God shaped our genomes to be like his.
3. God modified his DNA (in specific cells) to be like ours.
4. The problems from apparent chromosomal mismatches were overcome in some other fashion.

I doubt that Jesus's abiltiy to lay down his life and take it up again was due to any coding in his genome, so I don't think it really matters. Helaman 5:11 says "And he hath power given unto him from the Father to redeem them from their sins because of repentance." Furthermore we do not receive priesthood power by any biological means, so I don't see why Jesus's unique abilities were necessarily genetically based. Similarity in appearance could probably be achieved without much trouble. (Just a couple of weeks ago somebody told me that I look exactly like their younger brother. And for that matter, I've run into somebody that looked a whole lot like my younger brother.)

My point is that perhaps we should be more careful in using the 46 chromosome argument because it raises more questions than we are prepared to answer.

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Lewis, Freud, and The Question of God

Last fall I picked up and read (mostly) the book, The Question of God, by Dr. Armand M. Nicholi, Jr. A program by the same name, based on the book, aired on PBS as well. The purpose of the book is to compare and contrast the lives and worldviews of C.S. Lewis and Sigmund Freud. Dr. Nicholi is an associate professor of clinical psychiatry at Harvard Medical School where he has taught a course on Lewis and Freud for more than 25 years.

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The Book

The intention of the book is to engage Lewis and Freud in a virtual conversation and to examine how their philosophies influenced their lives. There is no evidence that they ever met and Freud died long before Lewis did, so in a sense Lewis has the last word. Lewis, of course, was an atheist for much of his life but eventually converted to Christianity and wrote prolifically. On the other hand, Freud was the foremost atheist and materialist of his time.

I do not claim to be a student of C.S. Lewis, although I have read Mere Christianity and Miracles, as well as several of the Narnia series--I am even less familiar with Freud. For those who have a casual interest, but do not have a thirst to read the many writings of these two men, this book is the one to read--even if you are only interested in one of them. The book deals with a number of topics including belief in God, conscience and moral law, and the nature of happiness, sex, love, pain, and death. Each chapter contains selected writings of both Freud and Lewis, as well as biographical components that relate to the topic under discussion.

Although the chronology may be partly to blame, it seems clear that the author favors Lewis's worldview. If you are an admirer of Lewis this book will not challenge--and will most likely enhance--your opinion of him. One of my favorite parts is the discussion of Lewis's conversion, which was facilitated in part by J.R.R. Tolkien. Although Lewis's conversion may not match my experience, I find it insightful and faith-promoting nonetheless. (Quick digression: When the first Lord of the Rings movie came out, a member of my ward said that his father-in-law, who probably had not seen the movie, called the movie "anti-Christian." I'll give you "violent", or "not appropriate for young viewers", but "anti-Christian?" I explained that this could not be as Tolkien helped convert Lewis to Christianity!)

I was not impressed by the picture painted of Freud. He seems to me to have been a prideful, miserable man who disliked most people. Although he was a poster-boy for atheism, one senses that deep down he was insecure about his rejection of God. In one way, Freud was somewhat redeemed in my eyes. If I understood Dr. Nicholi correctly, Freud used the term "sexual" in a very broad way. Thus the strange sexuality popular culture attaches to Freud's name appears to be a misunderstanding of his thinking. Also, in my view, Freud's confrontation and discussion of the dark side of human nature has merit in that it is a study of the natural man. I thought this connection was insightful:

One of Freud's theories that has proved helpful clinically relates to the unconscious process of transference, the tendency to displace feelings from authority figures in our childhood onto those in the present, thus distorting and causing conflict with the present authority...We must be careful that our concept of God--whether the God we reject as unbelievers or that we worship as believers--is firmly based on the Creator revealed in history and not on our neurotic distortion of Him.

The "discussion" between Freud and Lewis is a little disappointing in that Freud seems largely irrelevant to today's atheists--not that I'm any expert on atheism. However, if I'm not mistaken Freud has been largely discredited on other grounds, thus it seems to me that Lewis is largely shadow-boxing. I would be more interested in how Lewis's arguments fit into today's discussion.

Nevertheless, I recommend the book and think it worth reading, if only to understand Lewis better.

The PBS Program

The program was in two parts of two hours each. I only saw the first part but I was not all that impressed. The production had value in that it was somewhat of a documentary of the life of Lewis and Freud. Interspersed throughout the program were discussion sessions led by Dr. Nicholi. The guests were a range of believers (not necessarily Christian) and non-believers. One notable non-believer was Michael Shermer of Skeptic Magazine and Scientific American. For the most part I thought the discussions were worthless. I quickly tire of people rambling on about what they believe--especially when it consists of a bunch of platitudes and abstract ideas. Whereas a couple of the non-believers were pretty articulate, for the most part the believers did not seem persuasive to me. It reminds me of Elder Packer's story about "fighting out of context."

My advice is to read the book and pass on the PBS program.

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Homo floresiensis

If you are interested in hominid evolution at all, you should check out this article by Carl Zimmer discussing the recent Homo floresiensis find.

Here is a graphic to help orient you on relationships.

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Simon Southerton Responds

Simon Southerton, the author of Losing a Lost Tribe, has responded to several apologetic arguments. He'll have to excuse us (the believing LDS intellectual community) for not rolling over easy, but he is giving us an intellectual workout.

This criticism and response deserves highlighting:

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7. The bottleneck effect, genetic drift, and other technical problems would prevent us from detecting Israelite genes.

In 600 BC there were probably several million American Indians living in the Americas. If a small group of Israelites, say less than thirty, entered such a massive native population, it would be very hard to detect their genes today. However, such a scenario does not square with what the Book of Mormon plainly states and with what the prophets have taught for 175 years.

His answer confirms that this is a legitimate issue. At the same time, however, he tries to make us carry the weight of past commentary by church leaders and superficial interpretation of scripture. This is a critical point. It is like anti-Mormons who try to make us defend controversial statements by past prophets and apostles. I do not feel obligated to do so. I have no problem with most Native Americans being "adopted" Lamanites, if not literal descendants (see Stephens and Meldrum's article at FARMS).

I have not read Southerton's book and at this point am not inclined to, simply because I think I have a pretty good idea of the issues involved. His recent response seems like a pretty good summary to me. If anybody can give me good reasons to read it I might change my mind.

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Evolution of Snake Venom

The principle of natural selection has two components to it. First is the generation of diversity, which as far as we can tell is a random process. The second part is non-random--the survival and reproduction or death of an organism. The generation of diversity is often driven by mutation of genes. The definition of "mutation" that immediately comes to mind is usually the simplest kind--single base-pair changes. Critics of evolution often express incredulity that such a process could be responsible for the diversity of life. One out-dated argument calculates the probablility of a particular amino acid sequence coming into existence at random and comes up with some astronimical number, thus showing that mutation could not be responsible for the existence of the protein.

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However, if we broaden the definition of mutation to be any changes in the genome, the picture becomes more plausible. New genes can be created in several ways, one of which is gene duplication. There are at least a couple of ways a gene can be duplicated--the specifics are not important here. Once a gene has been duplicated, the forces of mutation (in the stricter sense) and natural selection can play on one copy while the other copy retains its original function. Often mutation will render the new copy junk, resulting in a pseudogene. However, sometimes a new function can be gained.

This is apparently how snakes evolved venom. New research indicates that most venomous proteins made by snakes are very similar to proteins contained elsewhere in the snake's body.

From Science News:

By comparing the venom gene sequences with other known sequences, Fry was able, in three-quarters of the cases, to infer which gene had duplicated. He found that the various toxins traced their way back to proteins that play diverse roles in an assortment of organs, from the brain to the testes. For example, proteins in the acetylcholinesterase group are common neurotransmitters for muscle control, but the snake's venomous form induces paralysis and difficulty breathing; similarly, kallikrein proteins regulate blood pressure, but the toxic versions induce a fatal drop in blood pressure.

From Nature News:

"Despite the incredible changes in bioactivity that occur, the basic molecular scaffold and three-dimensional shape doesn't change notably," Fry says. The results of his analysis appear this week in Genome Research.

So here we have an example of a novel biological function arising from existing genetic information.

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BYU: A House of Faith

A few of weeks ago I blogged about Michael Ash's article, "The Mormon Myth of Evil Evolution." I raised the question of documentation for a rumored rift between David O. McKay and Joseph Fielding Smith. Since nobody knew the source for sure, I emailed Michael Ash to find out. His computer files were not available at the time, but he was pretty sure his source was Brigham Young University: A House of Faith, by Gary Bergera and Ron Priddis. The book is out of print now, so I bought a used copy on-line for a few dollars--a good investment in my view. It does appear to be the source for the rift rumors. However, the supposed rift is only mentioned in passing and is contradicted by others, as pointed out by Justin.


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I find the book quite interesting since it details various developments and controversies at BYU over the years, with many behind-the-scenes views. There is a 40-page chapter on organic evolution at BYU which is certainly worth reading. I've been particularly impressed with Dallin Oaks's administration on a number of issues. Among them, he seems to have been instrumental in getting the sciences at BYU a little breathing room.

When Dallin Oaks replaced Ernest Wilkinson as BYU president in August 1971, he soon learned of serious problems on campus regarding the role of evolution at the university. In his first address to the faculty in September he asked that guilty parties, particularly among members of the religion faculty, "stop casting aspersions on [the] testimony and devotion of their colleagues" in the sciences.

(It strikes me that it isn't only science professors who can live in ivory towers.)

He also initiated a series of seminars to facilitate dialogue between the science and religion faculty, although some religion faculty apparently refused to attend. (Elsewhere, Duane Jeffery says that one of the religion faculty wrote a 4(?) page letter on why he would not participate in anything that Satanic.)

Shortly after Duane Jeffery published "Seers, Savants, and Evolution: The Uncomfortable Interface," the then Elder Benson spoke at a BYU fireside and said

"one of our church educators [has] published what he purports to be a history of the church's stand on the question of organic evolution...To hold to a private opinion on such matters is one thing,...but when one undertakes to publish his views to discredit the work of a prophet [ie. Joseph Fielding Smith], it is a very serious matter."

Jeffery promptly wrote to Oaks, emphatically denying that he was on a "campaign to disparage the reputation of anyone." While he had decided not to respond publicly, he explained, his "silence should not be construed as a concession" to Benson's criticisms. Sympathetic, Oaks replied, "I am hopeful and confident that with a little love and understanding and patience and patience and patience that these things will work out."

(Elsewhere, Jeffery says that the then Elder Benson had not actually read his article, but got his information from an aspiring underling who had distorted the article.)

At a later point, Oaks wrote the following to the then Elder Hinckley:

There is a clear issue here: Should the board continue or should it revise its policy that permits Brigham Young University faculty to teach the theory of organic evolution--teaching it as a theory and not as a proven fact?

...If we stopped teaching this theory, within a few years students from BYU would not be admitted to...graduate schools. At that point we would cease to function as a recognized university and would, in the eyes of the world (especially the world of higher education), be little more than a seminary with added courses in the humanities.

...There are thousands of our faith who feel threatened by that openness, and while I have sympathy with that as a personal point of view, in my judgment that kind of narrowness should never be allowed to impose the darkening hand of censorship on this university."

In fairness we should keep in mind, as Stephens and Meldrum point out in their book, that much of the best supporting evidence for evolution has come forth since 1970. Man, His Origin and Destiny was published only a year after the structure of DNA was solved. But the Jeffery episode does raise some interesting questions. Setting aside doctrinal disagreements, if Joseph Fielding Smith's book contained inferior scientific arguments, should the LDS scientists have remained silent--thus appearing to have no answer for JFS's claims? It seems like a tight rope to walk and I'm glad such tension is largely set aside these days.

It came much later, but the BYU packet (available on the side bar), I think, was a great idea and protects both points of view. It also diplomatically frees us from having to account for every statement made by every General Authority (including JSF) because it emphasizes the role of First Presidency Statements.

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