Skip to comments.THE THIRD WAVE (Sympatric Speciation)
Posted on 02/03/2011 7:44:55 AM PST by James Oscar
I was fortunate enough to interview her on a wide variety of topics. That conversation has lasted several years. The first four discussions are linked below. This is final discussion in that series.
I have tried to be as accurate as possible in reporting this work. Any errors that appear stupid are obviously mine.
A: Be glad to help.
Q: I titled this project as The Coming Wave due to the first conversation we had up at the lake. What I would like to do now is to go back and address that issue in great detail.
When I was writing the first article in this series I tried to give a rough image of your worldview and your vision for the future. I did a terrible job transmitting that information and as a result several websites that were hosting my work were flooded with complaints.
Now that I have laid a better foundation on which to build that conversation, I would like to explore your concept of the Coming Wave with you.
A: It seems a perfect day to do so.
Q: You have been retired for a very long time now; do you miss working in the field?
Q: When we spoke at the lake, for the first time, your opinions were very new to me and, in all honesty, somewhat shocking. I had never known someone with strong religious beliefs who also believed in evolution.
A: It is not as unusual as you might think. In fact the more you study the workings of the universe the more you find yourself in awe of the beauty.
Q: And you feel that man is subject to both evolution and to God's will?
A: Why would you think that evolution is not God's will?
Q: Well I don't know. Isn't evolution a physical system that functions independently?
A: So is the morning dew and so is the rainbow. But to insist that the Creator did not create the operating system for his work is a bit naive.
Q: Operating System?
A: Why yes, evolution, gravity, electromagnetism and sex are all part of the big picture that makes this rare and wonderful experience not only exist, but change and constantly evolve. If you ever study fractals you can see that there may even be simple patterns or elements used over and over in varying magnifications. Sort of like building blocks but way more complex.
And, of course, we know now that the condition we once called chaos is all smoke and mirrors. Chaos is simply highly complex rhythms that, at this time, are beyond our understanding. And this is not a sermon about not knowing God, but simple mathematics.
We know for a fact (thank you Mitchel Feigenbaum) that the mathematical process whereby an orderly system moves into the realm of chaos is highly structured and a mathematically beautiful rhythm.
Then we lose our way. The rhythms are just too complex. That does not mean they don't exist, because they do - just that we do not have that level of perception yet.
Q: Perception. I see. Actually I have done some reading that has helped me understand why you always cite order vs. chaos as an example of perception. I have very limited math skills, but I can understand the significance of being able to predict events right up to, and a little ways, into chaos. It is interesting reading.
A: It is that predictability that is so important. The more in tune we are to our environment and the dynamics that it operates under - then the more we can understand and predict change.
Q: That makes very good sense to me. So when you speak of being worried about challenges to our continued population growth (as a species) are you using that predictability?
A: Very much so. While we may be the overwhelmingly dominate species on this rock, it would be sheer vanity to believe that we exist out of the normal, natural processes of life. It just is not true.
Our species is subject to all the forces that influence, regulate and contain population growth - we are not Gods. However it is our ability to understand and react to those forces - and that is our strong suit.
Q: What kind of forces are you talking about?
A: Well the most basic dynamic is simply this: Is the birth rate larger than the death rate? If the answer is yes then you are in an era where the species is expanding.
Q: Haven't we always expanded as a species?
A: No, not at all. We have had a number of events that we call bottlenecks. A population bottleneck is where a significant percentage of any species is either killed or prevented from reproducing.
There have been a number of these events in our history, but the time-line, severity and number of bottlenecks is a very hotly debated subject. It depends a lot on which gene you backtrack.
But there is a general consensus that we might have been reduced to perhaps only 5,000 reproducing females around 70,000 years ago.
That is a very large event and the genetic implications of such a bottleneck are equally significant.
Q: So there is a history of dramatic reductions in the size of the population of our species?
A: Of course, we are not above the biological forces that regulate all life.
Q: I have a bit of a faux pas to admit to you.
A: And what would that be?
Q: In my first article, where I was trying to summarize your views on this subject, I used the term the thinning of the herd - and was severely castigated on several of the sites that were posting my thread. It almost crashed my project.
A: It is a very loaded expression. Many very ugly ideologies are associated with that phrase. It implies human intervention and some sort of selection process - like in animal husbandry. Bottlenecks in species are not like that at all. Often it is just a function of geography or climate.
There are, of course, dominate trends in these occurrences. I had a colleague who put it this way: "Among the classical markers of a species in crisis are sexual dysfunction and disease."
Q: Sexual Dysfunction?
A: Well to put a finer edge on it - reproductive dysfunction. We mammals have evolved a behavioral and physiological response to any population crisis.
When a mammalian population becomes dangerously dense, there is a reversal of behavior. Co-operation is replaced by competition, dominance and aggression.
If this sounds familiar to you - it should. Also in these times of population stress you will find infanticide and gross neglect. The resulting stress and violence also impairs both the immune and the reproductive systems. That is why epidemics often complete the crash of the population.
In some mammal species, crisis and crisis response recur regularly, leading to cycles of population growth and relapse, oscillating about a fixed mean. Here you can think almost any wildlife species - deer and coyotes are very much in the news now because of exactly these factors.
Q: Is it true for humans as well?
A: Well, in man successive advances in food production have made possible geometrically growing populations, and unlike other animals, we can choose to check population growth by reducing the birth-rate, instead of raising the death-rate, as in other mammals.
However, even with a flood of abortions, China's single child policy, Europe's low birth rate and other measures we are still on a very sharp curve.
No - we are very much in the same stew as our more furry friends.
Q: When we first met at the cabin you told me that you had grave concerns about our near future as a species. Is that still your position?
A: Yes it is.
Q: When you try and discuss it with people do they think you are odd?
A: Why do you ask?
Q: Because I believe that you see way more than you have ever discussed with me and that you are super careful not to disclose any of these theories with anyone - because people are largely idiots.
A: People are not idiots.
Q: Yes they are, if you in any way upset their perfect little vision of reality they get defensive and nasty. Now I am not saying the people who read your threads are like that but those folks are a very small minority of the population.
Your everyday Joe wants to hear about how hope and love always conquer and if you tell them truths they do not want to hear - they will get violent. That is why I say that. But I believe I am not telling you anything you don't know. You live the recluse lifestyle and keep your own counsel because your true thoughts disturb people.
A: I believe that you paint the picture much too dark. It is true that this is a subject more suited to Hollywood than casual conversation. But it is not true that people would rather not know.
We must never put ourselves into a position where we believe that information should be filtered. The heart of science is that knowledge is shared. Even our conjectures, opinions, and observations are distributed. The very soul of science has been tempered on ridicule and even persecution.
The road to understanding our world is paved with open discussion. So being challenged in ones belief is no roadblock to any true person of science.
And if I may say so, it should never be an impediment to your profession as well.
Q: Touché, I didn't mean any offense.
A: I know that.
Q: It is just that I would like to go even farther into your observations but I fully intend to publish your comments on the Internet. And I do not care to diminish your reputation.
A: (Laughing) - my reputation?
Q: Well you know what I mean.
A: Yes I do, and God bless you for caring but I am so far past such considerations that it seems a bit unnecessary. These are the days in my life where I am only concerned with God's opinion of my actions.
So perhaps we can agree to just have our little discussion and let others form their own opinion. OK?
Q: Good by me.
A: What is it that you would like to know?
Q: I have read some of your writing about the great apes; do you feel they are near extinction?
A: Well the non-human great apes are not doing that well, but we humans are quite successful. All non-human great apes are endangered species. Actually there are very few breeding populations outside of captivity.
It is a sad story and it is not getting any better. Great apes or Hominidae not only include humans but chimpanzees, gorillas and orangutans.
In Africa the bushmeat trade is wrecking havoc on the primate population in the wild, and the periodic outbreaks of Ebola are killing breeding adults also. We have about 200,000 western gorillas and only about 6,000 eastern gorillas left. It is crunch time for their species and with the exception of those in captivity the prognosis is poor.
These are our closest relatives. This is not an abstract lesson in Biology - this is real and it very bad.
Homo erectus and Homo neanderthalensis, at one point in time, were in exactly the same situation as our mountain gorilla is now. Their populations became isolated and their breeding numbers declined to the point where their species failed.
Q: Well our numbers arent declining.
A: No they are not. We have about 6.8 billion humans spread out over every ecosystem on earth and a few brave souls living off the earth in orbit.
We are, in fact, living in a human population explosion. Tens of thousands of years passed before our species reached the one billion mark, around 1804, it then took only 130, 33, 15, 13 and 12 years to add each succeeding billion. This accelerating rate of increase is what is meant by the term population explosion. Not that hard to see really. We are expanding as a species at a faster and faster pace.
Would you agree that we are indeed in a human population explosion?
Q: Seems clear to me.
A: Then there are only two outcomes available. When we speak of population explosions within a species we normally resort to a bit of geek speak where we describe the two outcomes as either a r-selected species or k-selected species. What this means, in simple terms, is that an r-selected species is one that reproduces quickly, has a short maturation time, breeds at a young age, has a short lifespan, produces many offspring quickly, has small offspring, has a high mortality rates for their young, and give little or no parental care.
The "K-selected species" usually live near the carrying capacity of their environment. Their numbers are controlled by the availability of resources. In other words, they are a density dependent species. The attributes of a K-selected species include a long maturation time, breeding relatively late in life, a long lifespan, producing relatively few offspring, large newborn offspring, low mortality rates of young, and extensive parental care.
The main point of R/K selection theory is that evolutionary pressures tend to drive animals in one of these two directions towards quickly reproducing animals whose specialty is to adopt as many niches as possible using simple strategies or slowly reproducing animals who are strong competitors in crowded niches and invest substantially in their offspring.
The quick summary of R/K selection theory can be thought of as quality vs. quantity.
Q: Then we are obviously K-selected species?
A: It is open for discussion.
Q: You said only two outcomes, what are they?
A: Well in the R-selected species their populations explode, filling all the ecological niches they can endure and then they suddenly collapse with the glide ratio of a rock.
The K-selected species also explodes while food and habitat are abundant, and then they slow down as regulatory factors such as lower birth rate and reduced food availability come into play. The rate of population growth slows down to zero, and the population reaches a fairly stable level.
Q: Are we leveling off?
A: Yes and no. No - we are still increasing the human population on earth but yes we are now slowing that rate of increase.
Q: When did it start slowing down?
A: Somewhere in the early 60s we reached our peak of a 2.2% increase and then we began to moderate that rate of growth. We now have about a 1.14% rate of growth which translates to doubling in 61 years.
Q: Has it been continually slowing?
A: Yes, for the last 40 years.
Q: So if I understand correctly, we are modulating our population as we reach the limits of the environment.
That sounds like good news, is it?
A: Well, lets take a look at a very simple equation that will help us decide the answer to that equation.
r = n - m
This simple equation means that the realized intrinsic rate of growth is measured by the difference between natality (birth rate) and mortality (death rate).
And obviously zero population growth is reached when r = 0, natality equals mortality, and the population size remains constant, even though individuals are being born and are dying.
It seems simple. To follow the perfect example of a perfect k-selected species - we would simply expand to the limits of our environment or as we often say the habitat’s carrying capacity - we would then modulate our birth rate to equal our death rate and live in the land of milk and honey.
But it is, as are many things in complicated systems, not that easy. We now understand that there are both k-selected and r-selected traits in many populations. Our species is riddled with such contradictions.
Let’s start with a simple concept like rate of population growth. While it is true that the overall human rate of increase is modulating - that is not true for all components of that set.
Most European countries have low growth rates. In the United Kingdom, the rate is 0.2%, in Germany it is 0.0%, and in France, 0.4%. Germany’s zero rate of growth includes a natural increase of -0.2%, without immigration, Germany would be shrinking, like the Czech Republic.
The Czech Republic and some other European countries growth rate is actually negative (on average, women in the Czech Republic give birth to 1.2 children, which is below the number to yield zero population growth, approximately 2.1 children). The Czech Republic’s natural growth rate of -0.1 can not be used to determine doubling time because the population is actually shrinking in size.
So in these numbers we have a very strong trait for k-selection. But there is another current equally as strong - if not stronger. Many Asian and African countries have high growth rates. Afghanistan has a current growth rate of 4.8%, representing a doubling time of 14.5 years.
Q: I thought k-selected species also had rapid population expansion?
A: The answer is yes; of course k-selected species have periods of rapid population expansion. But the kicker is the conditions under which this occurs.
Do you remember the brief phrase I said summarized the k vs. r selection?
Q: Was it quantity vs. quality?
A: That is correct. But what it also means is that these two strategies are designed to function in different environments. Your K species uses the rapid growth to take advantage of a stable environment with ample resources while the R species responds to a disturbed environment by mass reproduction - obviously hoping that some members will survive the certain crash that always occurs.
So it is not just the growth rate but the environment that frames that growth that really defines which strategy is in play. We have in the k-selected species a stable environment that is density dependent. They produce few offspring with extra investment on the part of the parent, they have late maturation (again with much parental care) and they live long lives.
The r-selected species thrives in an unstable environment where there is density independence, they produce many offspring with limited parental investment, and they have early maturation, and live short lives.
Q: I don’t understand are you saying we are not a k-selected species?
A: No, we are both. Although some organisms are primarily r- or k-strategists, the majority of organisms falls between these two ecological extremes and may display traits of both. Because this concept of a continuous spectrum is such an important concept to understand - I would like to take a moment and discuss it with you.
One way to speak of a continuous spectrum is to frame it in terms of variations within a species. You are quite aware that within any species you have wide differentiation. Size, coloration, abilities etc, it is a never ending list of differences that make God’s creation such a wondrous joy.
These differentiations are the result of all the possible combinations of genes in an individual member of any species.
So we can say that the intermediate expression of genes results in a wide variety of variations within any species. Pretty much ABC stuff but it is incredibly important in the discussion we are having.
Q: Why is that?
A: Because not all answers are yes and no. And not all problems are black and white. We were discussing how it is impossible to describe the human species as either a r-selected or a k-selected species because we present traits of both evolutionary strategies.
Our species presents a range of these traits across a wide spectrum of expression. It is not one way or the other. Even among the scientific community there is great confusion about this dynamic. We have scientists who have attempted to attribute these variations in strategies to race.
It was a foolish error from the beginning. The variations within any given race are as great as or greater than between any two races. When you read about this type of speculation always remember that this type of racial stereotyping has been postulated for generations and it is as bogus as it comes.
The variations are real, but they are exclusively related to behavior and nothing else.
That behavior is motivated by countless different factors but it is not attributable to race.
Q: OK, I think I understand that we are largely a K species but that within our species there are many different behaviors, some of which are K and some of which are R. Is that close?
A: Yes, this bit of explanation has to do with the famous r = n m, the equation that lets us see if we are expanding, stabilizing or shrinking as a species. Now we know that r (the rate of increase has been modulating downward for the past 40 years) but it is still in the positive range.
Because we as need to determine if the species is indeed modulating it’s r to the point of 0 and achieving balance with it’s environment and not just posting a small dip in a 600 year upward trend - we must examine the data closely.
And, as we have been discussing, that data is very mixed. Some cultures are into negative population growth (think the Czech Republic and some other European countries) while some cultures are expanding rapidly. (Think Latin America, the Middle East and Sub-Saharan Africa).
China is at 1.7 and India is at 2.8 in total fertility rates. So even among the most populous countries there is a difference. And these differences can lead to huge outcomes. With India above the 2.1 replacement rate in fertility and China below the norm it would only take to the year 2040 for India to be the most populous country on earth.
But again, predicting future growth rates of any population is very risky business - that is why we are taking such pains to be as accurate as possible in our evaluation of that old pesky r = n - m.
Q: OK, so if I read this right you are saying that there still might be a case for the r-selected behavior to overwhelm the k-selected behavior and instead of leveling off either continue expanding or to crash? Is there any way to know for sure?
A: Yes there is.
Q: In all honesty, I don’t see how, over the short term, k type behavior can overcome the population explosions evident in some parts of the world.
A: Remember, there are trends and countertrends in many countries or cultures - even modernized societies.
Let us take England for a moment. That is as about as proper an established modern country as can be found. Do you know what the most common name given boys at birth in England was last year? Here is a hint Jack has been the most popular for 14 years in a row.
Q: William or Harry?
A: No, the correct answer would be Mohammed.
Q: For real?
A: Yes of course, it is once again the collision between two different evolutionary currents. Immigration from other countries is sparking a baby boom in some areas while the resident population is declining as a whole.
It is an uneven picture. One wave is reproducing and spreading while the other current is falling further and further behind even meeting the fertility rate necessary to maintain their population.
That is what we mean when we speak of differentiation between members of a species. Differentiation in reproductive strategies to the same environment is a pretty telling marker of evolutionary conflict.
Q: I believe that I have a good handle on this subject now; can I summarize what I have heard?
A: Of course, go ahead.
Q: This discussion originated when we speculated on the future of our species in a changing environment. You have since tried to teach me some of the dynamics involved in making such a prediction. What I now understand is that from the beginning our species has been subject to at least two different evolutionary strategies involving reproduction, fertility rate and species expansion. Good so far?
A: Excellent, and especially the part where you say at least two, because there are many factors involved - but these two paradigms are easiest to understand. Please go on.
Q: Our current large population numbers are the results of countless surges, crashes and plateaus of population growth. During this long evolutionary development, some varieties of humans have risen to prominence then completely disappeared due to competition from a better adapted group.
A: There is nothing wrong with the word variety but you might be better served to use the term groups.
Q: Point taken. These surges in population growth by one or more groups are described, by you, as waves. I am assuming you are drawing that term from something like the sine wave
A: Of course.
Q: There have been large waves like the one out of Africa, the one across the Bering Strait and the expansion of the Old World into the new. But there have been lots of smaller waves within those events - like Clovis Man and others.
The current wave started after the Black Death and the migration to the New World. That wave (which you and I have been calling the First Wave) rolled across the planet and finally peaked in the early 60s.
From that time on the rate of increase in the total number of humans has been slowing. However, there are cross currents within that decrease in rate - as there are with many other species.
I also understand that there are very distinguishable traits associated with what is called an r-selected species, such as early maturity, a large number of offspring, limited or no parental long term investment in these offspring, and that this behavior normally leads to a rapid expansion of that species and a sudden collapse in their numbers.
There are also distinguishable traits associated with what is called a k-selected species, such as late maturation, few offspring and a large investiture in those offspring, and that this behavior typically leads this group to fully occupy the habitat, at that point their numbers level off and arrive at some type of balance with their environment.
A: That is pretty close.
There is one caveat that I should add. In old school Biology we would normally think of any single species as either K or R selected. The understanding that there are multiple expressions of both these traits within any given species, while not controversial, is new. Not a large point but one that could be questioned.
Q: I understand that, although it is difficult to see how you could not see the different strategies in our species.
A: Agreed. OK, now that the first wave is modulating, what else.
Q: Well, there is now The Second Wave rising out of the developing world. As the developed countries have lower and lower fertility rates, other parts of the world are doing exactly the opposite. I am not sure where the rates are the highest but I would guess Africa.
A: When you look at just births per woman in her lifetime you come up with Niger at 7.19, Guinea at 7.07 and Afghanistan at 7.07. But why is that still misleading?
Q: Because of infant mortality?
A: Oh, not just that but life expectancy at birth. While fertility may be very high in Niger the life expectancy at birth is only 40 years old. Africa, as a whole, has a life expectancy of around 54 years, but it obviously varies from area to area.
Q: That sounds like exactly what an r-selected group would try to do. In a challenging environment where life is short you try to produce a lot of offspring. Right?
A: Yes, and that was an excellent summary. As you point out - due to the sub-replacement fertility of much of the industrialized world - population decline is a real factor. Japan, for instance, has been in a state of population decline for a number of years.
We know this by using our handy little r=n-m formula. After the 2005 census we discovered (in Japan) for the first time that r was a negative number (meaning that the number of deaths outnumbered the number of births).
But it was to be expected, Japan has the second lowest birth rate in the developed world after only South Korea. That rate of 1.4 is not enough to sustain a population thus r = less than 0. And when r = less than 0, you may have a problem. What do you think?
Q: Well not necessarily. If you are modulating your growth at an optimum level then an r of 0 or slightly less than 0 might be expected.
Q: The problem, I suppose, is determining whether you are leveling or plunging.
A: Population decline, or depopulation, can be cyclic or benign but it is sometimes a harbinger of bad times.
Some Japanese towns facing depopulation are offering cash. Yamatsuri offers parents $4,600 for the birth of a child and $460 a year for 10 years.
The Republic of Singapore offers $3,000 for the first child, $9,000 in cash and savings for the second; and up to $18,000 each for the third and fourth. Why isn’t this option being offered in Europe and other areas with sub-replacement fertility rates?
Q: Because of immigration?
A: Yes. Were it not for immigration a large number of countries would be facing very serious depopulation issues. In the past decade the UK population level has been rising as fast as it did at the peak of the post-war baby boom in the early 1960s.
About 45 per cent of last years population rise was brought about by immigration and 55 per cent by a greater number of births than deaths. However the rising birth rate is itself a product of immigration one in four births last year were to mothers who were born outside Britain.
To summarize, we have the First Wave modulating growth and the Second Wave rushing in to fill the gaps in desirable locations where depopulation is an issue.
This immigration results in a rapid expansion of the new group with large, extended families. It would seem a balanced response when viewed in this manor, but it is not.
Q: Are you talking about the culture conflicts that develop?
A: No, culture is like Jello. It is always changing and reshaping itself. The issue we need to concern ourselves with - is the one of species survival. Our problem, as a species, is that we are facing a Third Wave.
It is the factor that makes any extrapolation from the data we have been discussing moot. The Second Wave rising out of the developing world is being overtaken by the deadly Third Wave - and it is targeted at our very existence.
Q: You say there is a Third Wave coming. Is this to be in our lifetime?
A: It is not coming - it is here. While we discuss very small outbreaks of every exotic disease known, the real killer keeps penetrating our species until it has reached global saturation.
And that saturation of geography and culture is now complete.
Say hi to Mother Abigail!