Quotes & Sayings


We, and creation itself, actualize the possibilities of the God who sustains the world, towards becoming in the world in a fuller, more deeper way. - R.E. Slater

There is urgency in coming to see the world as a web of interrelated processes of which we are integral parts, so that all of our choices and actions have [consequential effects upon] the world around us. - Process Metaphysician Alfred North Whitehead

Kurt Gödel's Incompleteness Theorem says (i) all closed systems are unprovable within themselves and, that (ii) all open systems are rightly understood as incomplete. - R.E. Slater

The most true thing about you is what God has said to you in Christ, "You are My Beloved." - Tripp Fuller

The God among us is the God who refuses to be God without us, so great is God's Love. - Tripp Fuller

According to some Christian outlooks we were made for another world. Perhaps, rather, we were made for this world to recreate, reclaim, redeem, and renew unto God's future aspiration by the power of His Spirit. - R.E. Slater

Our eschatological ethos is to love. To stand with those who are oppressed. To stand against those who are oppressing. It is that simple. Love is our only calling and Christian Hope. - R.E. Slater

Secularization theory has been massively falsified. We don't live in an age of secularity. We live in an age of explosive, pervasive religiosity... an age of religious pluralism. - Peter L. Berger

Exploring the edge of life and faith in a post-everything world. - Todd Littleton

I don't need another reason to believe, your love is all around for me to see. – Anon

Thou art our need; and in giving us more of thyself thou givest us all. - Khalil Gibran, Prayer XXIII

Be careful what you pretend to be. You become what you pretend to be. - Kurt Vonnegut

Religious beliefs, far from being primary, are often shaped and adjusted by our social goals. - Jim Forest

We become who we are by what we believe and can justify. - R.E. Slater

People, even more than things, need to be restored, renewed, revived, reclaimed, and redeemed; never throw out anyone. – Anon

Certainly, God's love has made fools of us all. - R.E. Slater

An apocalyptic Christian faith doesn't wait for Jesus to come, but for Jesus to become in our midst. - R.E. Slater

Christian belief in God begins with the cross and resurrection of Jesus, not with rational apologetics. - Eberhard Jüngel, Jürgen Moltmann

Our knowledge of God is through the 'I-Thou' encounter, not in finding God at the end of a syllogism or argument. There is a grave danger in any Christian treatment of God as an object. The God of Jesus Christ and Scripture is irreducibly subject and never made as an object, a force, a power, or a principle that can be manipulated. - Emil Brunner

“Ehyeh Asher Ehyeh” means "I will be that who I have yet to become." - God (Ex 3.14) or, conversely, “I AM who I AM Becoming.”

Our job is to love others without stopping to inquire whether or not they are worthy. - Thomas Merton

The church is God's world-changing social experiment of bringing unlikes and differents to the Eucharist/Communion table to share life with one another as a new kind of family. When this happens, we show to the world what love, justice, peace, reconciliation, and life together is designed by God to be. The church is God's show-and-tell for the world to see how God wants us to live as a blended, global, polypluralistic family united with one will, by one Lord, and baptized by one Spirit. – Anon

The cross that is planted at the heart of the history of the world cannot be uprooted. - Jacques Ellul

The Unity in whose loving presence the universe unfolds is inside each person as a call to welcome the stranger, protect animals and the earth, respect the dignity of each person, think new thoughts, and help bring about ecological civilizations. - John Cobb & Farhan A. Shah

If you board the wrong train it is of no use running along the corridors of the train in the other direction. - Dietrich Bonhoeffer

God's justice is restorative rather than punitive; His discipline is merciful rather than punishing; His power is made perfect in weakness; and His grace is sufficient for all. – Anon

Our little [biblical] systems have their day; they have their day and cease to be. They are but broken lights of Thee, and Thou, O God art more than they. - Alfred Lord Tennyson

We can’t control God; God is uncontrollable. God can’t control us; God’s love is uncontrolling! - Thomas Jay Oord

Life in perspective but always in process... as we are relational beings in process to one another, so life events are in process in relation to each event... as God is to Self, is to world, is to us... like Father, like sons and daughters, like events... life in process yet always in perspective. - R.E. Slater

To promote societal transition to sustainable ways of living and a global society founded on a shared ethical framework which includes respect and care for the community of life, ecological integrity, universal human rights, respect for diversity, economic justice, democracy, and a culture of peace. - The Earth Charter Mission Statement

Christian humanism is the belief that human freedom, individual conscience, and unencumbered rational inquiry are compatible with the practice of Christianity or even intrinsic in its doctrine. It represents a philosophical union of Christian faith and classical humanist principles. - Scott Postma

It is never wise to have a self-appointed religious institution determine a nation's moral code. The opportunities for moral compromise and failure are high; the moral codes and creeds assuredly racist, discriminatory, or subjectively and religiously defined; and the pronouncement of inhumanitarian political objectives quite predictable. - R.E. Slater

God's love must both center and define the Christian faith and all religious or human faiths seeking human and ecological balance in worlds of subtraction, harm, tragedy, and evil. - R.E. Slater

In Whitehead’s process ontology, we can think of the experiential ground of reality as an eternal pulse whereby what is objectively public in one moment becomes subjectively prehended in the next, and whereby the subject that emerges from its feelings then perishes into public expression as an object (or “superject”) aiming for novelty. There is a rhythm of Being between object and subject, not an ontological division. This rhythm powers the creative growth of the universe from one occasion of experience to the next. This is the Whiteheadian mantra: “The many become one and are increased by one.” - Matthew Segall

Without Love there is no Truth. And True Truth is always Loving. There is no dichotomy between these terms but only seamless integration. This is the premier centering focus of a Processual Theology of Love. - R.E. Slater

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Note: Generally I do not respond to commentary. I may read the comments but wish to reserve my time to write (or write off the comments I read). Instead, I'd like to see our community help one another and in the helping encourage and exhort each of us towards Christian love in Christ Jesus our Lord and Savior. - re slater

Showing posts with label Science and Population Genetics. Show all posts
Showing posts with label Science and Population Genetics. Show all posts

Tuesday, December 16, 2014

Biologos - Adam, Eve and Human Population Genetics, Part 3: Language, populations and speciation


Adam, Eve, and Human Population Genetics
Part 3 -
Language, populations and speciation
http://biologos.org/blog/adam-eve-and-human-population-genetics-part-3-good-butter-and-good-cheese

In this series, we explore the genetic evidence that indicates humans became a separate
species as a substantial population, rather than descending uniquely from an ancestral pair.

by Dennis Venema
December 12, 2014

In yesterday’s post, we drew an extended analogy between genetic change within a population over time, and change within a language over time. While no analogy is perfect, this one is remarkably good – and it will continue to be useful as we now turn to discussing how new species form.



Flags of Friesland and England

With a last name like Venema, it will come as no surprise to many that I have Frisian ancestors. Friesland is a province of the Netherlands with a distinct language, West Frisian, that is one of the most closely-related modern languages to English. My paternal grandparents, immigrants to Canada in the post-World War II era, spoke a delightful hodge-podge of English, Dutch and Frisian to each other, often using mostly Frisian and only reverting to Dutch or English if it happened to have a better word for the concept at hand. As a child, I remember hearing Frisian and noting how similar many of its words were to their English equivalents – far too many similarities, I thought, to be merely coincidence. A well-known sentence will serve as an illustration: it is pronouncedessentially the same in both Frisian and English:
Butter, bread, and green cheese is good English and good Frise.

Bûter, brea, en griene tsiis is goed Ingelsk en goed Frysk.

Later, I would come to understand the reason for these striking similarities – English and West Frisian are modern descendants of an ancient language – they share a common ancestral population of speakers. As we have seen, languages change over time. In the case of English and West Frisian, the original population, which spoke a language ancestral to both modern-day English and modern-day West Frisian, was divided: some remained on the European continent, and others travelled to what is present-day England. Once separated, each sub-group – which at the point of separation spoke the same language – went on to acquire differences over time that were independent of each other. In due time, the changes that accumulated in both groups rendered them mutually unintelligible to each other: they had become separate languages. The precise point at which they became “different languages” of course is impossible to pin down, since there was no such precise point when it occurred. Both groups changed their language over time incrementally, as a process on a gradient.

Species form through a process much like language development. Should two populations of the same species become separated, they too can accumulate genetic changes that shift their average characteristics over time – changes that are not shared and averaged across the two groups due to their genetic isolation. In many cases, geographic isolation acts as the first genetic barrier – much like the ancestors of the English parting ways with their continental cousins. Once separated, should enough genetic changes accrue between the two populations, eventually they will not recognize each other as members of the same species – which would be analogous to my experience as a modern English speaker in present-day Friesland.

Species, like languages “begin” as populations – and “begin” isn’t the right word

Our language analogy also helps to counter some common misconceptions about how species form. Often when I am speaking about human origins, folks who have heard about modern humans descending from around 10,000 ancestors wonder how on earth those 10,000 people suddenly appeared on the scene without ancestors. Of course, they didn’t suddenly appear – they too have a population that gave rise to them, and so on – stretching back to our shared ancestral populations with other apes and beyond. There is in fact no point in our evolutionary history over the last 18 million years or more where our lineage was reduced below 10,000 individuals – and 18 million years ago our lineage was not even close to “human” in any sense, since this timepredates any hominin (i.e. species more closely related to us than to chimpanzees) in the fossil record. The 10,000 number is simply the smallest population size we have in our history over the last several million years. The lineage leading to modern humans experienced what is known as a population bottleneck, a time when our ancestral population size was reduced to around 10,000 breeding individuals, only to expand again afterwards.

Despite these explanations, it is a common misperception to think that species, should one go back far enough, started off with one ancestral breeding pair “becoming different”. Hopefully our language analogy is useful here. It is of course not reasonable to expect that English or West Frisian got its start when two individuals began speaking a new language. The lineage that led to either modern language did so as a population of speakers – and each generation within both lineages was perfectly intelligible to their parents and their offspring. In the same way, species form as populations shift their average characteristics over time – but always remaining the “same species” as their parents and their offspring. So, to speak of a language or a species “beginning” is to hit up against the limits of language. Neither “begins” in some sort of discontinuous sense – they become, over time, in continuity with what came before.

So, one of the reasons for the common expectation that humans had a discontinuous beginning with a single ancestral couple has nothing to do with Genesis or Judeo-Christian theology: I have met many non-theists who also have this same expectation. We are used to thinking in discontinuous terms – species should have a defined beginning – and we are used to thinking that species therefore begin with a radical change to a single ancestral pair. For evangelical Christians, these incorrect assumptions about how species get their start fit hand in glove with the common view that since species require a discontinuous start, only God can miraculously provide it through an event of special creation. Once one understands how species form as populations over time, however, one is then prepared to investigate the question of how large our population was as we became human – a question we will begin to address in the next post.

For further reading:



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Dennis Venema is professor of biology at Trinity Western University in Langley, British Columbia. He holds a B.Sc. (with Honors) from the University of British Columbia (1996), and received his Ph.D. from the University of British Columbia in 2003. His research is focused on the genetics of pattern formation and signaling using the common fruit fly Drosophila melanogaster as a model organism. Dennis is a gifted thinker and writer on matters of science and faith, but also an award-winning biology teacher—he won the 2008 College Biology Teaching Award from the National Association of Biology Teachers. He and his family enjoy numerous outdoor activities that the Canadian Pacific coast region has to offer. Dennis writes regularly for the BioLogos Forum about the biological evidence for evolution.









Biologos - Adam, Eve, and Human Population Genetics, Part 2: A premier on population genetics


Adam, Eve, and Human Population Genetics
Part 2 -
A premier on population genetics
http://biologos.org/blog/adam-eve-and-human-population-genetics-part-2-a-primer-on-population-geneti

In this series, we explore the genetic evidence that indicates humans became a separate
species as a substantial population, rather than descending uniquely from an ancestral pair.

by Dennis Venema
December 10, 2014

Evolution as gradual change at the population level

One of the most common misunderstandings about evolution is failing to appreciate that evolution happens topopulations, not individuals. But, you might interject, populations are made up of individuals – so how does that work? The answer is that yes, genetic variation enters a population through mutations in individuals – but that only when such variation accumulates within a population and shifts its average characteristics do we observe its effects.

Perhaps an analogy will help here – one that I have used before, that of language change over time. Languages are like populations – they have a large number of individuals who speak it. While each individual has their own particular quirks (favorite phrases, word preferences, and perhaps even chronic spelling mistakes) any one person cannot, on the whole, cause significant change to their language within their lifetimes. Additionally, any person who does change radically from their language group will effectively be placing themselves outside it – if their changes are large enough to hinder their intelligibility to others. So, language evolution is not an individual affair. Yet languages do change over time, and individuals do contribute to that change. Someone might invent a new word that catches on, for example. Others might be part of the “catching on” – hearing a new word, or new phrase, and repeating it to others. Over time (perhaps generations) a language will slowly adopt new words, new spellings, and new rules of grammar (such as split infinitives in English – to boldly split what no man has split before – but I digress). Yet, such adoptions are gradual. They enter the language as rarities, slowly become more common, and eventually become the “normal” way of doing things (much to the chagrin of English teachers). Thankfully, such changes typically take longer than one generation, sparing those of us who cringe at the novelties of our day. If the English words “there, their and they’re” ever officially collapse into one word determined solely by context or the use of apostrophes to form plurals becomes standard, I’m thankful I won’t be here to see it.

Just as a language has many speakers, a species has many members. They must be genetically compatible – i.e. speak the same language – but they are not all genetically identical – they have their own particular variation within an acceptable range to be in the group. In other words, though populations are a unit (they interbreed) they have genetic variation.

In the terminology of genetics we can understand this in terms of genes and alleles. While all members of the population have the same genes, they do not all have exactly the same version of any given gene. Different versions of a gene are called alleles, and they arise through mutations – that is, copying errors when chromosomes are replicated. For humans, we may have up to two different alleles for any gene – the allele we inherit from our mother, and the allele we inherit from our father. If have two different alleles, we are said to beheterozygous for that particular gene. If we have two identical alleles for a gene, we are homozygous for that gene. While any individual can have up to only two alleles, populations as a whole can have hundreds or even thousands of alleles.

In any given generation, the vast majority of the alleles present in a population were inherited from the previous generation – just like a language group learning from their parents, and picking up the language as a whole, but also some of their particular linguistic quirks. Each generation also can contribute its own novelty to the population in the form of new alleles arising through mutation – just like teenagers coming up with new words or phrases. These new alleles, are rare of course – they are only held by one individual at the beginning. Over many, many generations, however, such new alleles can become more common within a population if they are passed down, progressively, to more and more offspring. In time, the new allele might become the most common one within a population. Many generations later, it might be the only allele present for that gene in the entire population. Combined with the actions of other new alleles of many other genes, over time the average characteristics of the population can change. While it’s challenging to imagine this for genes and alleles, it’s simple to illustrate with language – for example, the change we see in linguistic trajectory towards present-day English in a verse from John’s gospel:


John 1:29, West Saxon Gospels, c. 990

Anothir day Joon say Jhesu comynge to hym, and he seide, Lo! the lomb of God; lo! he that doith awei the synnes of the world. (Wycliffe Bible, 1395)

The nexte daye Iohn sawe Iesus commyge vnto him and sayde: beholde the lambe of God which taketh awaye the synne of the worlde. (Tyndale New Testament, 1525)

The next day Iohn seeth Iesus coming vnto him, and saith, Behold the Lambe of God, which taketh away the sinne of the world. (KJV, 1611)

The next day John seeth Jesus coming unto him, and saith, Behold the Lamb of God, which taketh away the sin of the world. (KJV, Cambridge Edition)

The next day John saw Jesus coming toward him and said, “Look, the Lamb of God, who takes away the sin of the world!” (NIV, 2011)

Note well that these “forms”, as we see them here, themselves have many gradations between them, of course. These selections are useful for our illustrative purposes, however. Note that the overall shift to the “modern” text is the cumulative result of many individual changes. To return to our analogy, if every word is a gene, we see shifts in alleles over time as follows:

cwæð → seide → sayde → saith → said

synne → synnes → synne → sinne → sin

to hym cumende → comynge to hym → commyge vnto him → coming vnto him → coming unto him

Though the changes in each word contribute to the overall transformation, each word has only a relatively minor effect on its own. Yet the combined actions of changes in many words, over time, can change West Saxon to modern English. There are not, however, large jumps at any point along the way – each generation of speakers could easily understand their parents and their children – but over time, the shifts are large enough that West Saxon and present-day English are not even close to being the same language.

In the next post in this series, we’ll consider how changes in alleles can lead to new species – much like change over time can lead to new languages.

For further reading:


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Dennis Venema is professor of biology at Trinity Western University in Langley, British Columbia. He holds a B.Sc. (with Honors) from the University of British Columbia (1996), and received his Ph.D. from the University of British Columbia in 2003. His research is focused on the genetics of pattern formation and signaling using the common fruit fly Drosophila melanogaster as a model organism. Dennis is a gifted thinker and writer on matters of science and faith, but also an award-winning biology teacher—he won the 2008 College Biology Teaching Award from the National Association of Biology Teachers. He and his family enjoy numerous outdoor activities that the Canadian Pacific coast region has to offer. Dennis writes regularly for the BioLogos Forum about the biological evidence for evolution.









Biologos - Adam, Eve, and Human Population Genetics, Part 1: Scripture, science, and defining the issues


Adam, Eve, and Human Population Genetics
Part 1 -
Scripture, science, and defining the issues
http://biologos.org/blog/adam-eve-and-human-population-genetics-part-1-scripture-science-and-definin

In this series, we explore the genetic evidence that indicates humans became a separate
species as a substantial population, rather than descending uniquely from an ancestral pair.

by Dennis Venema
November 12, 2014

Note: In this series, we explore the genetic evidence that indicates humans became a separate species as a substantial population, rather than descending uniquely from an ancestral pair.

Back in 2011, Christianity Today ran a cover article on what was fast becoming a hot-button issue for Evangelicals – the genomic science that indicates humans descend from a large population, rather than from a single couple in the relatively recent past. Since 2011 Evangelicals have become increasingly aware that modern genetic studies of humans support this conclusion; however, there remains a great deal of confusion about exactly how this genetic evidence works, and, not surprisingly, suspicion about its accuracy. In this series, we will explore several lines of genetic evidence that shed light on our species’ past in an attempt to rectify these misunderstandings.

Defining the issues

Part of the challenge this subject generates for Evangelicals is due to confusion over exactly what the science can and cannot say about human origins in general, or the historicity of Adam and Eve in particular. Briefly stated, genetics is well suited to addressing scientific questions such as whether humans share ancestry with other forms of life, and what our population structure looked like as we separated from our evolutionary relatives. And what we see in the genetics of our species is unremarkable for a relatively large-bodied mammal – we do indeed share common ancestry with other species, and we descend from a large population that has never numbered below about 10,000 individuals throughout our evolutionary history. Scientifically speaking, these issues are straightforward and uncontroversial.

In addition to these scientific questions, however, Evangelicals are also strongly interested in the question of Adam and Eve’s historicity: were they a literal couple that lived about 6,000 – 10,000 years ago? Unfortunately, genomic science is not at all equipped to address this question – it simply does not have the ability to establish (or rule out, for that matter) the historicity of any particular individual in the ancient past.

For many Evangelicals (or for that matter atheists), the idea that we are the products of evolution and became human as a large population over time is on its face contradictory to the idea that Adam and Eve may have been historical individuals. The reason, of course, is not a scientific one, but rather an interpretation that the Genesis narratives preclude understanding Adam and Eve as anything other than the first humans, directly created by God without shared ancestry, who are the sole genetic progenitors of the entire human race. This is, of course, a very common evangelical interpretation of Genesis, but it is not the only one – several other options are available that attempt to respect both Scripture and science. After all, Genesis has long been noted to imply that Adam and Eve’s family is part of a larger unrelated population (for example Cain worries about being killed for his sin, leaves to build a city elsewhere, and takes a wife in the process). The fact that Genesis presents these facets of the story without comment or clarification also shows us, in my opinion, that the narrative is simply not concerned with telling the story of our genetic origins, but rather is focused on theological concerns.

So, the decision to equate the historicity of Adam and Eve with the expectation that humans descend uniquely from an ancestral couple is a hermeneutical one, not a scientific one. As such, the historicity question needs to be addressed hermeneutically, not scientifically – it simply lies outside the purview of what genetics can tell us.

Evolution as a population-level phenomenon

Aside from the hermeneutical issues surrounding human evolution and population genetics (which are confusing enough for many of us), there are the scientific issues – which, for many Evangelicals, are similarly fraught with misunderstanding. One of the main misconceptions is failing to understand that evolution is a population-level phenomenon: species form slowly, as populations, due to the accumulation of numerous slight genetic differences that shift the average characteristics of a population over time. All that is required to start this process is to have some sort of genetic barrier between two populations – perhaps a geographic barrier to start. Once two populations of the same species are reproductively isolated, genetic changes in the one population are not shared with the other – and vice versa. Over many, many generations enough changes may accumulate in the two populations that their average characteristics are different enough such that they would no longer recognize each other as members of the same species. At this point, even if the two populations were brought into contact again, these differences (perhaps behavioral or physical) would keep the genetic barrier in place by reducing or preventing interbreeding, and thus prevent the two groups from collapsing back into one large population.

If, on the other hand, one is used to thinking that species form when they are founded by a pair that has undergone a marked genetic change compared to their source population, one is more likely to think that it would have been possible for humans to get their start in such fashion. These sorts of misunderstandings are common among non-scientists, and Evangelicals are not immune to them. For example, even among Christians who accept that we share ancestry with other life, I frequently get asked what “the mutation” was that “made us human”. Sometimes, folks wonder how such a dramatic mutation could have occurred in two individuals at the same time to provide a male and female member of the same (brand new!) species – and speculate that God must have directed it to occur to form Adam and Eve. Their understanding of human speciation is that it was sudden, involved only one couple, and required dramatic genetic change. In reality, speciation is almost always precisely the opposite: it’s slow, takes place in a population, and requires the accumulation of many discrete genetic differences, none of which are particularly dramatic. In the next post in this series, we’ll begin to explore how a population can accumulate genetic changes, and perhaps shift its average characteristics over time – beginning with how genetic diversity arises in the first place.

For further reading



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Dennis Venema is professor of biology at Trinity Western University in Langley, British Columbia. He holds a B.Sc. (with Honors) from the University of British Columbia (1996), and received his Ph.D. from the University of British Columbia in 2003. His research is focused on the genetics of pattern formation and signaling using the common fruit fly Drosophila melanogaster as a model organism. Dennis is a gifted thinker and writer on matters of science and faith, but also an award-winning biology teacher—he won the 2008 College Biology Teaching Award from the National Association of Biology Teachers. He and his family enjoy numerous outdoor activities that the Canadian Pacific coast region has to offer. Dennis writes regularly for the BioLogos Forum about the biological evidence for evolution.



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