May 24, 2019

Is There Purpose in Biology?  The Cost of Existence and the God of Love. By Denis Alexander, Chapter 2: Biology’s Grand Narrative

Is There Purpose in Biology?  The Cost of Existence and the God of Love. By Denis Alexander

Chapter 2: Biology’s Grand Narrative

We are reviewing the book: Is There Purpose in Biology?  The Cost of Existence and the God of Love. By Denis Alexander.  Chapter 2 is Biology’s Grand Narrative.  In this chapter Alexander asks the question: “What happens when we look at the general features of biological evolution – the overall “grand narrative” – in the light of the claim that it is necessarily purposeless?  What do we actually observe?”  His first chapter point is that we observe increased complexity over time.  The first 2.5 billion years things rarely got bigger than 1 millimeter across.  There were no birds, no fish in the sea, no animals wandering around.  Gradually, through photosynthesis and other factors complex and not completely understood, the oxygen in the atmosphere built up to the 21% levels of today.  Another major transition came with the development of multicellularity.   Once multicellularity evolves, there is a huge scope for increased specialization in cell functions and in the construction of organs.  There is good evidence that multicellular forms of life have evolved many times independently from all three forms of single-celled life, the bacteria, the archaea (archaea constitute a domain of single-celled microorganisms. These microbes are prokaryotes, meaning they have no cell nucleus.), and the eukaryotes (an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus).

Figure 1 from the book gives the example that Alexander is talking about.  Multicellular volvocine algae first started appearing 220 million years ago.  Somewhere at some time a single –celled alga divided and the two daughter cells remained embedded in a chemical known as a glycoprotein.  So from now on this chemical binding meant that different cells had to contribute to the common good, at least as far as that organism was concerned.  It is then possible to track through the fossil record what happened next.  Different cells became specialized for different functions already by 200 million years ago.  Some cells started specializing in motility, in movement, and so they had to sacrifice their own reproduction.  As the author of a recent review comments: “The importance of cooperation, conflict and conflict mediation in the early stages of the transition is likely a general principle for origins of multicellularity” (Herron, M.D. 2009. Many from One: Lessons from the Volvocine Algae in the Evolution of Multicellularity.  Communicative & Integrative Biology, 2:368-70).

Figure 2 from the book illustrates the main point in the present context that, taken overall, evolutionary history has seen a huge increase in complexity as assessed by the sheer diversity of plants and animals.  It is the “big picture” which is so striking.  Alexander quotes evolutionary biologist Sean Carroll from the University of Wisconsin-Madison in a Nature interview:

Life’s contingent history could be viewed as an argument against any direction or pattern in the course of evolution or the shape of life.  But it is obvious that larger and more complex life-forms have evolved from simple unicellular ancestors and that various innovations were necessary for the evolution of new means of living.  This raises the possibility that there are trends within evolutionary history that might reflect the existence of general principles governing the evolution of increasingly larger and more complex forms.

Alexander himself notes:

As we stand back and look at the sweep of evolutionary history, we see huge creativity in life, immense diversity, but in a highly organized way, in which the ways of being alive for both animals and plants are constrained by the physical necessities of living on a planet with light and darkness, with this particular gravity, with particular atmospheric conditions at particular times, with particular temperature ranges.  So, given carbon-based life, there do seem to be only so many ways of being alive on planet Earth.

Alexander then brings out the second main chapter point that has come to light in recent decades; that of convergent evolution.  Convergent evolution is the process in which organisms that are not closely related independently evolve similar features.  It is often thought that evolution is a purely random process and that over the billions of years since life began the process might have gone in any direction, not necessarily resulting in the kind of intelligent life-forms we see on the planet today.  The question of evolution’s predictability was notably raised by the late paleontologist Stephen Jay Gould, who advocated the view that evolution is contingent and unrepeatable in his 1989 book Wonderful Life. “Replay the tape a million times … and I doubt that anything like Homo sapiens would ever evolve again”.  Gould also famously likened evolution to a drunk on a sidewalk staggering around in a random manner.  Alexander takes up and unpacks the meaning of “random” and “chance” in Chapter 4, so I will wait for that chapter to have that discussion.

The person who has done the most in recent years to investigate and popularize the idea is Simon Conway Morris, Professor of Evolutionary Paleobiology at Cambridge.  His research group has also developed the Map-of-Life website highlighting many examples of convergence.  The site says: “The name “Map of Life” reflects the way that evolution has repeatedly arrived at, or converged upon, the same adaptive solutions from more or less unrelated starting points, as though evolutionary trajectories were following a metaphorical “map” to the same destination.”

In the chapter, Alexander spends some time discussing the development of “camera eyes” in cephalopods (octopuses, squid and cuttlefish), cubozoans (jellyfish), and vertebrates (i.e. humans).  This website lists “10 Striking Examples of Convergent Evolution in the Animal Kingdom” which would include:

1.       Ichthyosaurs and Dolphins

2.       Sparassodonts and Cats

3.       Phytosaurs and Crocodiles

4.       Foxes and Thylacines

5.       Hedgehogs and Echidnas

6.       Hyenas and Dogs

7.       Tapirs and Pigs

8.       Hyracodonts and Horses

9.       Mudskippers and Tiktaalik

10.   Placodonts and Turtles

Alexander notes:

This brief section on convergence in eye evolution has only just touched the surface of a huge subject.  If you live on a planet of light and darkness, you are very likely to get eyes at some stage of evolution.  The adaptive advantages are huge and obvious.  This even led Dawkins to suggest that evolution is “progressive”, a notion Darwin himself found problematic, Dawkins writes, “the cumulative build-up of complex adaptation like eyes, strongly suggests a version of progress – especially when coupled in imagination with some of the wonderful products of convergent evolution.”

In a commentary on Gould’s idea of ultimate randomness in evolutionary history, Conway Morris writes that it is:

… now widely thought that the history of life is little more than a contingent muddle punctuated by disastrous mass extinctions that in spelling the doom of one group so open the doors of opportunity to some other mob of lucky-chancers… Rerun the tape of history of life… and the end result will be an utterly different biosphere.  Most notably there will be nothing remotely like a human… Yet, what we know of evolution suggests the exact reverse: convergence is ubiquitous and the constraints of life make the emergence of the various biological properties (e.g. intelligence) very probable, if not inevitable.

Two other major evolutionary products that seem to be ubiquitous are cooperation and intelligence.  Another related striking feature of evolutionary history is the rapid increase in brain size in hominids that has taken place over the past 2 million years, in which the brain more than tripled in size from around 400 cc all the way up to an average 1300-1400 cc.

Alexander concludes that, as we look at the “grand narrative” of evolution, taken as a whole, the claim that it is necessarily Purposeless begins to look increasingly implausible.  There is an obvious arrow of evolutionary time – from ultra-simplicity to incredible complexity.  We cannot avoid the constrained features of the evolutionary process, dependent ultimately upon the laws of chemistry and physics.  Constraint and convergence are all around us.

I think he makes a very strong case here… and he’s not done yet.

Comments

  1. I find this very interesting and at times even understandable. My heart filled with pride that some of my ancestors and even living relatives are mentioned in this article. They may be labeled by some as drunks on a sidewalk staggering around in a random manner but if my family history research is correct they were either looking for the restroom or the next open bar. There was a pattern and purpose to their staggering leading to the evolution of the present day Barry gene pool that has a high tolerance for alcohol . They may have staggered but they staggered with purpose and drank with a goal, to get drunk, they had no constraint.

    Will be interesting to see how this series evolves. It is absolutely fascinating to ponder the mysteries of life including the complexity of this world. I at times stagger though life at random without being drunk and good or bad things just happen but probably would be replicated in the same precise manner. What a wonderful world.

  2. Adam Tauno Williams says

    Hmmm.

    > There is an obvious arrow of evolutionary time – from ultra-simplicity

    Yet very simple organisms [relatively speaking] continue to exist in the mix, potentially as a majoritarian share by volume. It doesn’t seem necessarily like a movement.

    > Constraint and convergence are all around us.

    Well, yeah. Respectfully, I don’t see “it”.

    Physics and the particulars of our atmosphere only provide a few particular ways to fly: wings generating lift, heat-to-decrease-density, or lighter-than-air. And you get air plains, hot air balloons, and dirigibles.

    > in which the brain more than tripled in size from around 400 cc all the way
    > up to an average 1300-1400 cc.

    Notably this only appears to have happened in one particular species [or one line of species of which only one sample currently exists]. There are some interesting possibilities why that is [aside from that we killed all the other ones].

    • Mike the Geologist says

      “Yet very simple organisms [relatively speaking] continue to exist…” That’s like asking if evolution is true, why are there still apes. C’mon you know better.

      “Well, yeah. Respectfully, I don’t see “it”.” He gave you the example of camera eyes and wings. Plus I included 10 examples of convergent evolution. What is it you don’t see?

      The Figure 2 Biodiversity graph, I thought, was pretty clear. The fossil record supports Alexander’s contention. It can be argued to what degree, and Conway Morris has his critics, but it is a defensible position.

      • Adam Tauno Williams says

        “””an obvious arrow “”” is what I do not see, and was referring to above.

        Yes, there is an increase in complexity.

        An arrow Moves, leaving where it was, going somewhere else. It has a trajectory. Yet in Evolution the previous Levels-Of-Complexity remain; all those things remain, they don’t move. In fact, it is those simple things that endure as the much more complicated things continually get plowed under, demonstrating far less durability than their simpler brethren. The Ant and the Roach have trundled through waves of mass extinction.

        Perhaps it is more like a branch which grows upwards and the gardener comes by every few months and lops it off again. 🙂

        Convergent Evolution is an Obvious Truth. I certainly agree with this: “””We cannot avoid the constrained features of the evolutionary process, dependent ultimately upon the laws of chemistry and physics. Constraint and convergence are all around us.”””

        Maybe all I mean is that, as a metaphor, I see more of a Trough than an Arrow. Of course the water will run down the Trough – – – it is water in a trough. Perhaps that is all he means.

  3. Christiane says

    JOE !

    🙂

  4. The main problem here is that it is impossible to extrapolate from a single example. This is why the search for a past or present extraterrestrial eco-system is so important. We simply don’t know what we don’t know.

    However the argument in this post is still a variation on our old friend Mr Argument From Design. And it has the inherent weakness of that argument. We tell design by comparing it to non-design. But if everything is designed how do you make that distinction? The argument undercuts itself.

    I look forward to the chapter on “randomness” since this idea is the source of much confusion.

    • David Greene says

      This is a very good point! We have a sample of one universe and if it is designed how would we know as we don’t have an example of a non-designed universe to compare it to. Paley’s watchmaker is an analogy of man designed things compared to non-man designed things extended to allegedly God designed things. The fallacy is while we have lots of man designed things and non-man designed things to compare we do not have that for God designed vs. non-God designed things given the sample of one universe. That is how I see it.

    • Very good point. If the universe is designed by a creator, then everything in it is designed. We indeed would have no way of comparing what is designed with what is not, because we have no instances of non-design.

    • Klasie Kraalogies says

      This is a excellent comment.

  5. Headless Unicorn Guy says

    There is good evidence that multicellular forms of life have evolved many times independently from all three forms of single-celled life, the bacteria, the archaea (archaea constitute a domain of single-celled microorganisms. These microbes are prokaryotes, meaning they have no cell nucleus.), and the eukaryotes (an organism consisting of a cell or cells in which the genetic material is DNA in the form of chromosomes contained within a distinct nucleus).

    Out of curiosity, does anyone remember the Eighties game Sim Earth?

    Where the game would announce “EUKARYOTES HAVE EVOLVED! (boop boop boop beep beep beep)”?

  6. No fan of intel design here but it makes sense to say evolution has goals and a direction in my opinion. The ability to fly evolved three separate times, at least; first with insects, then reptiles that apparently morphed into birds, and then mammals like bats. It is destiny that creatures will exist that will fly. What follows is my conjecture. If conditions are right, this could have occurred and be occurring on other planets. Likewise, on such other planets, it seems their higher animals could become social and organize into herds and packs. What would there be to stop that? And what happens when eventually some of them develop language ability? They develop religion. Eventually, agriculture breaks out. That changes their religion. They invent the wheel and move from stone tools and weapons to metal ones. That further changes how they organize and manage their ways of being. They have an axial age. They have their Buddha-like figure and their Christ. And perhaps other alternatives or examples of which we are not aware. This could be one way that the cosmic Christ has meaning. Nevertheless, given the vast distances of space this might never be discoverable.

    • flatrocker says

      So if I’m hearing you correctly…..

      One tiny little atom

    • Christiane says

      “the cosmic Christ”

      I love that phrase, Steve A.

      finally someone pulls the lens back far enough to reflect the Lord Who Is ‘from the ages to the ages’ 🙂

      I’m reminded of a story about the famous anthropologist Margaret Mead to do with the FIRST sign of ‘civilization’:
      “He (Brand) remembered a lecture he heard given by anthropologist Margaret Mead, who spent much of her life researching prehistoric peoples. She asked her audience, “What is the earliest sign of civilization? A clay pot? Iron? Tools? Agriculture?”
      No, she claimed, it was a healed leg bone.
      Brand recalls:
      She (Mead) explained that such healings were never found in the remains of competitive, savage societies. There, clues of violence abounded: temples pierced by arrows, skulls crushed by clubs. But the healed femur showed that someone must have cared for the injured person–hunted on his behalf, brought him food, and served him at personal sacrifice.”

      The idea that ‘order’ and ‘structure’ are eclipsed by ‘compassion’ and ’empathy’ as signs of ‘civilization’ appeal to my Christian sensibilities because the idea of self-sacrifice for the sake of ‘the other’ without thought of payment or personal reward seems somehow in line with the PURPOSE of Creation, at least in the final act, which would be befitting a Creator Who, by way of His own personal sacrifice, brings us from death into life.

  7. If you have selected an overcrowded room, it tend to be difficult you can get the jackpot quantity of.
    Once they are stacked, slowly lift the cards and bend them as if you are forming an arc. http://fwto.eu/22512liverunningstatus144933