Saturday, September 30, 2017

EVOLUTION: OFFBEAT IDEAS

Evolution: Offbeat Observations

Georg Lichtenberg said “It is impossible to carry the torch of truth through a crowd without singeing someone’s beard”, according to James Geary (2005, The World in a Phrase, Bloombury Publishing, New York, 229 pp.).  It somewhat comforts me as I write about the multiple errors earnest and intelligent researchers of evolution have made, errors I am trying to replace with a more accurate depiction of the tree of life.

One, of the two worst research reports establishing a faulty superphylum, Ecdysozoa, had a lady as the primary author; it made me realize the sexist nature of the aphorism quoted above.  I also do not know if the gentleman first author of the publication setting up the other faulty superphylum, Lophotrochozoa, had a beard to be singed.

The most influential zoologist of the last hundred years could well be Libbie Hyman.  See http://evolutioninsights.blogspot.com/2015/03/abandoned-theories-and-libbie-hyman.html  She deserves the respect given her, mistakes in her work are minimal, and I also do not want to detract from other work by the two authors whose work is criticized in http://evolutioninsights.blogspot.com/2013/05/science-screw-up-no-1.html , after all, “to err is human”.  I guess that proves I am human too.

When offbeat becomes main-stream evolution

Three of the last four blog posts have had bits about the abyssal ocean.  There are several facts about the abyss that can help us understand major consequences for evolution shaping life today in unappreciated but interconnected ways.

One, the stability of the abyssal region offered refuge from numerous early extinction events.

The extreme pressure, lack of light for photosynthesis, low input of surface debris reaching the abyss, near-freezing temperature, and sparse populations were ecological factors leading to the long-life, low reproductive rates, and emphasis on survival adaptations characteristic of K-selected life styles.  They contrast to r-selected life styles of organisms where abundant food and high predation lead to short lives, high reproductive rates, rapid growth, and perhaps higher evolutionary rates of most organisms in lighted, warmer surface habitats.

Two, the abyssal affects on embryology and metabolic rates

The low reproductive potential in the deep sea put such a high priority on survival that it selected for delayed specification of embryonic fate of cells so loss of a cell from an early embryo would not prevent normal development.  This led the transition from protostomes to deuterostomes that have the ability to have an early embryo divide and produce two individuals instead of dying like a protostome embryo would.  Pogonophorans are at the junction where this happened and they have a mix of protostome and deuterostome features.

As I have noted elsewhere, the extreme pressure is probably a factor slowing metabolic rates and extending life-spans in the abyss.  Several studies have shown respiration is slowed greatly beyond what colder temperatures alone would depress rates.  One of the most enlightening clues was that a brown bag lunch contained a sandwich and an apple, that sank to the ocean bottom many months before they were retrieved with the sunken research vessel, Alvin, and were both in fresh condition.  Similar food in cold seawater decayed within a few days.

The ocean layer and circulation patterns described in a recent blog show that oxygen levels below the oxygen minimum layer would be impossible to exist if respiratory rates at abyssal pressures were anywhere near rates normal in shallow water below the photic zone.

Three, it’s a bit complicated

but the things above help show the role of the pogonophorans as an intermediate that also accounts for some features of our development and structure that were first accounted for by the annelid theory of chordate origin, an abandoned theory that is correct when adjusted for the role of the pogonophorans.




Joseph Engemann    Emeritus Professor of Biology, Western Michigan University, Kalamazoo, Michigan    September 30, 2017

Tuesday, September 26, 2017

pre-Cambrian survival

I never knew  -  ‘till Kalamazoo

What did I not know until Kalamazoo?  There is a tremendous amount that I didn’t know, and still don’t.  But that is probably true for most of us.  What I am talking about is some of the events related to how we evolved over the past two billion years to become the dominant species on earth.  Our knowledge of evolution is riddled with gaps and errors, even though the general story of evolution by natural selection is probably close to the truth.  The last section tells of three important ways marine species may have been able to survive the intense extended period of pre-Cambrian asteroid bombardment.

Many that believe in God reject evolution because the sequence of chance and random events are not acceptable as work of a creator conforming to their concept of God.  Many scientists, especially biologists, have found it difficult to accept God as the creator because acceptance is not compatible with their concept of the chance and randomness involved in evolution.  Both may struggle with the chaos, disasters, evil, and other bad things they see in the world and want to blame God, or see it as evidence of God’s non-existence.

Stop for a moment, and think about something in your life that seemed bad, but in retrospect you see that it helped make you who you are.  There are numerous such occasions in the evolution of life that may have been essential for evolution to take its peculiar course over the last billion years it took to produce Homo sapiens.  If that doesn’t inspire you, read on, find out how important extinction events were in the course of evolution leading to us.

THE FIRST TEN BILLION YEARS

The “Big Bang” begs a question like the one asking “is there is a noise if a tree falls in the wilderness and there is no one there to hear it?”  Astrophysicists have an answer for the projected rapid expansion from the first relative speck to the slowing expansion, formation of elementary particles, elements, and the first generation of stars.  Condensation of materials into later generations of stars (after the extinction of some early ones) was responsible for the formation of heavier elements completing the materials needed for the evolution of life on planets with favorable conditions around stars like our sun.

We don’t need to know the details of the formation of our solar system.  It was probably similar to a billion other places of the expanding universe.  Whether the protoplanetary disks around the stars formed by condensation of more diffuse matter, or from emissions or explosions from the newly formed stars, sufficient matter ended up forming planets spinning and orbiting the sun.  Some planets had sufficient gravity to retain gases in their atmosphere and retain space debris striking them.  Planets tend to collect most of the debris as well as larger objects in their orbits.  The larger objects sometimes were captured in orbit as moons or impacted the planets with varying results.  The sun, with its massive gravity, probably collected many objects, even planets, that lost speed due to some collisions and fell into the sun.

Our moon does not have seas and atmosphere like the earth, so erosion has not obscured the craters produced by impacting meteors, comets, and asteroids.  In fact, the moon may have provided some protection to us from some that would otherwise have hit the earth.  Craters are much more numerous on the far side of the moon than they are on the lava fields of the near side.

Some worry more than necessary about the danger of an asteroid causing our extinction as part of a phenomenon much like he events terminating the dinosaurs.  It is remotely possible, but the solar systems planetary arrangement suggests that a much more stable system exists than the state several billion years ago.

Where would we be without asteroids?
 The irregular structure of some asteroids and craters or “pock marks” shows they had been stuck many times.  The presence of many moons and smaller satellites around the four largest planets, all beyond Mars, suggest that some were captured as moons and perhaps the collision with potential moons and or planets may have provided the fragments (asteroids) of the asteroid belt orbiting in space between the orbits of Mars and Jupiter.

Some of those fragments provided extinction-type events in decreasing frequency as they were swept up by earth, the moon, adjacent planets and their moons.  In the beginning impacting asteroids contributed mass to the earth.  They probably sped up some of the potential chemical evolution steps in the pre-biotic earth.  Perhaps their craters filled with water to make many experiments in addition to the intertidal pools where the chemical steps leading to organic life may have started. 

How life survived asteroids

The late pre-Cambrian is thought to have experienced a long period of more intense asteroid impacts.  The abyssal sea was so great a portion of the earth’s surface layer, and the cold polar seawater flowing toward the equatorial region had high density due to temperature and salinity that allowed it to gradually replace bottom water.  The process continued taking thousands of years to have bottom water reach the surface, just as happens today.  Animals able to adapt to the abyss had such an extensive area to inhabit it enabled some to survive even the worst asteroid hits.

A second method was the selection of cysts and other survival mechanisms used as overwintering, drought resistant, and dispersal stages that can emerge from somewhat suspended animation when conditions improve.  Such stages were already being selected by the rigors of surviving dry periods in freshwater temporary ponds as well as in saltwater pools along ocean shores.  Gemmules of sponges and statoblasts of bryozoans are cystlike asexual reproductive bodies, common among freshwater species but missing in marine species, suggesting such survival mechanisms are now less valuable for marine species in their more stable environment.


A third method is direct uptake of nutrients dissolved in seawater.  The mortality of marine species may well have boosted the dissolved organic matter content of seawater following an asteroid extinction event.  It may be an important method in today’s oceans for the survival of larval stages during dispersal, especially in species providing little yolk for nutrient reserves for the larvae.  Stephens, Grover C., and Robert A. Schinske  (1961, Limnology and Oceanography, 6:175-181.)  found that in ten phyla tested only arthropods did not take up amino acids from very dilute solutions in seawater.  Manahan and Crisp (1982, American Zoologist, 22:635-646) found dissolved amino acids could be taken up by bivalves from egg to adult stages.

The pogonophora benefitted by their living in the abyss, a relatively protected location of such great extent that remnants of the population might survive.  They also benefitted from the third method of direct uptake of dissolved nutrients in sediment water.  The "degenerate" appearance of the pogonophorans is part of an evolutionary step backward that laid the groundwork for the advance of animals to today's vertebrates.

Joseph G. Engemann   Kalamazoo, Michigan    September 26, 2017


Sunday, September 24, 2017

ISAIAH and EVOLUTION

ISAIAH

The Lord, via the author of Isaiah 55:7-9, advised the scoundrel to forsake his ways, and the wicked man his thoughts. “Let him turn to the Lord for mercy; to our God, who is generous in forgiving.  For my thoughts are not your thoughts, nor are your ways my ways, says the Lord.”

“As high as the heavens are above the earth, so high are my ways above your ways and my thoughts above your thoughts, says the Lord.”

Isaiah, in other chapters, also contains some of the best texts anticipating events surrounding the coming of the Messiah about seven centuries before the birth of Jesus.


Where does the above fit in with God’s method(s) of creation?

Just as Jesus tells us how people can look as the sky and predict the weather, he could tell us today to look at the evidence of the living organisms and their fossils and see the glorious power of God exhibited in all creation.  We might have to listen to Isaiah and accept the limitations of our thoughts where the evidence of nature is excluded.


Why didn’t Isaiah tell us about evolution?

Why should he?  If he did it was most likely abandoned- as unintelligible with all that stuff about subatomic particles, genes, and fossils- for having no relevance or value to things then known.  It is amazing, that ideas and information preceding computers and printing presses by 4000 years, got passed along as well as they did.

Is there anything that rationally connects God, science, and evolution?

Yes, a proper understanding of causality.


Joe Engemann      Kalamazoo, Michigan    September 24, 2017

Friday, September 15, 2017

OCEAN STRUCTURE AND EVOLUTION


OCEAN LAYERS

The tropical and subtropical regions of the oceans have three layers, an upper warm layer, an intermediate layer of rapidly declining temperature (the thermocline), and the bulk of the ocean extending to the bottom.  The intermediate layer is a zone where warm water mixes with colder deep waters.

The layers are maintained by density differences due to temperature and salinity; deep cold water is more dense or heavier than the upper layers.  The surface layer is typically from one hundred to one thousand feet thick.  It floats on top due to its expansion as it is warmed by the sun.  Most of the energy of sunlight that enters the water is absorbed in the first meter; below a few meters only blue light continues until it too is absorbed almost completely in the top 100 meters.

The depth, typically between 50 and 500 meters, of the mixing layer varies with wave and current action depending primarily on wind speed and density differences between the layers.  Constant winds produce higher waves and turbulence which induce deeper mixing.  Thus, the energy of the sun is absorbed and transported throughout the upper layer.  During a hurricane, the energy can be released from the water and strengthen the hurricane.  As the hurricane moves on, a new one may form if the surface water has not cooled much below 80 degrees Fahrenheit.

The winds of storms presumably enable the surface layer to be warmed to greater depths and thus store energy sufficient to produce additional and or stronger hurricanes.

Does global warming contribute to warmer oceans and more or stronger hurricanes?  Probably; a warmer air temperature increases the transfer of heat to surface water at the same time it reduces the rate of loss of heat from the water.

Do hurricanes contribute to ocean cooling, cooler weather, and a lull in hurricanes?  Presumably, hurricane winds increase cooling effect at the surface as turbulence in the upper layer transfers heat to an increasing depth of the upper layer as well as increasing the rate of heat loss at the surface from radiant energy, heat of vaporization of water, and direct water to air transfer.  The reduced water temperature increases the time needed to reach the temperature needed to generate a new hurricane.

THE CONSEQUENCES OF LAYERING

Layers make it more difficult to accurately measure the heat stored in the upper layer.  As warm water is pushed toward the margin of a continent it increases in height and depresses the layers below and forces water of the middle layer into a bulge of middle layer that moves as an internal wave.  The middle layer is squeezed between the lighter warm upper layer and the heavier lower cold layer, both being forced by gravity to seek an equilibrium of level layers.  At the border of the warm and mixing layers, the internal wave (called a seiche by scientists studying freshwater lakes) can have much greater height (relative to the upper surface of the middle layer) than surface waves and move more slowly across the ocean (lake).  I don’t know if oceanographers have studied hurricane induced seiches, but I would presume the initial movement would be a thickening of the near shore warm layer that would thin and push a bulge of the thermocline in a seaward direction.

The depth changes of the two interfaces, one of the mixing zone (thermocline) with the upper layer (epilimnion) and the other of the mixing zone with the lower layer (hypolimnion), may change by hundreds of feet in the ocean as an internal wave passes.  So calculating the energy stored in the ocean from a single location of a depth and temperature profile, or determining if the ocean is warming by a few measurements, is not very accurate if the profile changes with a passing internal wave or warm water is built up along a coast by constant onshore wind that then subsides.

The flooding from a storm surge in coastal areas rises above normal ocean levels as enormous waves break into low-lying coastal areas as they peak in shallow beachfront areas.  The magnitude of their intrusion is amplified by onshore winds, high tides, heavy rain, increased runoff from adjacent areas, and reduced runoff from normal channels or streams due to high ocean levels.

THE OXYGEN MINIMUM ZONE

Below the thermocline is an oxygen minimum zone where, light is insufficient for photosynthesis, and sinking dead organisms or their fragments provide nutrients for bacteria and other organisms to feed upon and deplete the oxygen in the process.  At the bottom of the deeper parts of the ocean, cold, salty, well-oxygenated water replaces bottom water that is slightly warmer.  The process of polar water replacing the deepest water continues until ten thousand or more years later the former bottom water approaches the oxygen minimum zone and becomes part of it until it enters the thermocline, eventually mixing with oxygenated surface water as well as being oxygenated by photosynthetic organisms when light is adequate.

The presence of oxygen gradually decreasing as water moves from the bottom to the oxygen minimum zone, and its long residence time, is evidence of the reduced biomass and long lives of individuals of the abyss.

EVOLUTIONARY CONSIDERATIONS

It should be obvious that the rigors and size of a hurricane have a potential to eliminate individuals less well endowed with survival adaptations of structure, physiology, and behavior.  It may be a tug-of-war between those survivors and ones better adapted to intervening weather and conditions. 

The stratification of the non-polar portion of the ocean, with the cold, sunlight-lacking, enormous abyssal zone covering over half of the earth’s surface, provides a place of refuge for species adapted to those conditions.  There are different ways of adapting, but one, the pogonophorans, have had security by living in a tube they secrete embedded in the sediments.  Like many others in the abyss, they have extremely long lives, low metabolic rates, and ability to take up nutrients from very low levels in the water.  Their circulatory system may be a critical component of their living deeply embedded in perhaps anoxic sediments while supplying oxygen to the embedded part for tentacles in the sea-water.  http://evolutioninsights.blogspot.com/2013/06/evolution-in-deep-sea.html

Joseph Engemann    Kalamazoo, Michigan    September 15, 2017