Created: September 9, 2015
Revised:Synopsis Sept 2017  

The Creation Narrative of Science and the Bible
 

Dr. David C. Bossard

Dr. David C. Bossard
Biographical Information


The Big Bang Creation of EukaryotesM.70

"An organic being is a microcosm, a little universe  formed of a host of self propagating organisms inconceivably minute, and as numerous as the stars in heaven."
Charles Darwin (1887)M.71

"The origin of eukaryotes is a huge enigma and a major challenge for evolutionary biology."
E. V. Koonin (2010)M.72

The most visible difference between prokaryotes and eukaryotes is the existence of a nucleus which holds the cell's DNA (see figure). This is only one of many important differences, some of which are mentioned below.

ProkEukDNA 

The sudden appearance of eukaryotes at about 1.8 Ga (Billion years ago), with no clear predecessors and with major structural and genetic changes, has been described as a "Biological Big Bang". Not only do the eukaryotes appear on the scene suddenly and without warning or obvious predecessors, but even within the major types of eukaryotes there is no clear line of antecedence—no clear "archeotype". Indeed the first eukaryote appears to be an example of "the magnates walk first"M.73—the (unknown) ancestor is more complex than any of the descendents. This is a recurring theme in the development of species.M.74

The first eukaryotic cells were single-celled (the protists), as bacteria are. Multicellular structures formed by cyanobacteria are actually individual single-celled microbes that live attached, and may have some cell specialization such as the nitrogen-fixing heterocysts and akinetes. But the structural and transport features of the proper cell have the potential for far more, and thus led in time to multi-celled species, and eventually to the visible, multi-cellular plants and animals.

There are six major groups of eukaryotes (see Wikipedia), and the inferred "common ancestor" must have been more complex than any existing (very complex) group. Many traits  of eukaryotes are unique to them and have no analog in bacteria.M.75

Features include:

• Eukaryotes are a radical advance in organizational complexity over all prokaryotes.

• All eukaryotes display a large package of genes that are unknown—let alone separately existing—in any prokaryotes.

• The genes that do appear to be shared with prokaryotes seem to be selected from both archaea and bacteriaM.76. There is no plausible scenario in which this might occur by natural evolution—even given lateral gene transfer, which is well-established, demonstrated in the laboratory, and can occur between unrelated species.

The following table lists some of the Eukaryote innovations. The mitochondria are the "powerhouse of the cell"—main producers of ATP, and use oxygen to do this: this is the reason why all eukaryotes require oxygen (even plants—derived from photosynthesis).

Eukaryote Innovations

Prokaryote
Eukaryote

DNA
Single loop in cell body
non-looped chromosomes in nucleus

Mitochondria
None
Membrane-bound organelle:
Consumes O2 to generate ATP energy "batteries"

Cell division
binary fission, a remarkable and complex process.
mitosis and cytokinesis (non-sexual cell division with mitotic spindle for division of cell & nucleus)
Sexual reproduction
None Meiosis to form sperm and egg cellsM.77
Structure
balloon-like: Shaped by pressure.M.78  See the range of shapes displayed in the Merck Manual. Cytoskeleton: shape & internal structure. See a chart of the many ciliate shapes.
Membrane-bound organelles
Absent
Organelles with controlled micro-environments for specialized tasks: the nucleus, nucleolus, mitochondria, golgi apparatus, endoplastic reticulum, etc.

Internal Transport
Diffusion—but some species have actin filiments that use Myosin motors in connection with muscle movement
Kinesin and Dynein use cytoskeleton "highways" for transport (see Figure below). Myosin uses a different highway of actin filaments and is used to reconfigure the cell (muscles for shaping; relocating organelles, etc). These highways are quite dynamic, constantly reconfiguring into new shapes and routes as needed. All of these transport motors use ATP "batteries" to supply energy. See Peter M. Hoffmann (2012) Life's Ratchet.
Programmed death
Absent
Ubiquitin found in all eukaryotes. Directs protein recycling (programmed cell death).

Kinesin
Kinesin

The invention of the eukaryotic cell came at a critical time in the history of the Earth, at a time when most of the reduced minerals in the oceans and Earth crust had oxidized and the atmosphere's oxygen content had reached a level that could poison cyanobacteria.

The invention of the original eukaryote could be another example of starting with a "magnate" (see above).  With the advent of detailed gene studies, one might have hoped that the problem of complexity of the first "proto-eukaryotes" might be solved, but thus far, such is not the case. Consider the following statement regarding the identity of the very earliest eukaryotes, summarizing a decade of intensive genetic research on the origin of the six major groups of eukaryotes:

"There are therefore no grounds to consider any group of eukaryotes primitive... Rather it is becoming increasingly clear that most or perhaps all of them evolved from more complex ancestral forms by reductive evolution. Reductive evolution refers to the evolutionary modality typical of parasites: they tend to lose genes, organelles and functions when the respective functionalities are taken over by the host. So the archezoan (crown group) phylogeny seems to have been disproved, and deep phylogeny and the theories of the origin of eukaryotes effectively had to start from scratch."M.79




[*fn]M.70 Koonin EV: The Biological Big Bang model for the major transitions in evolution. Biol Direct 2007, 2:21, "Major transitions in biological evolution show the same pattern of sudden emergence of diverse forms at a new level of complexity. ... In each of these pivotal nexuses in life's history, the principal 'types' seem to appear rapidly and fully equipped with the signature features of the respective new level of biological organization. No intermediate 'grades' or intermediate forms between different types are detectable."

[*fn]M.71   Charles Darwin, Animals and Plants, p.ii, p399 (1887).


[*fn]M.72 Koonin EV, "The origin and early evolution of eukaryotes in the light of phylogenomics", Genome Biology 2010, 11:209. He continues, "There is a sharp divide in the organizational complexity of the cell between eukaryotes, which have complex intracellular compartmentalization, and even the most sophisticated prokaryotes (archaea and bacteria), which do not... [R]econstructions show that the characteristic eukaryotic complexity arose almost ‘ready made’, without any intermediate grades seen between the prokaryotic and eukaryotic levels of organization. ... it is becoming increasingly clear that most or perhaps all of them evolved from more complex ancestral forms by reductive evolution."


[*fn]M.73  "Even the most widely accepted notion that eukaryotes originated from prokaryotes is problematic because traits unique to eukaryotes, such as the nucleus, endomembrane system, cytoskeleton, and mitosis, are found in all taxa with no intermediate stages left as signposts of their evolution."


[*fn]M.74  This is sometimes called Reductive Evolution.

[*fn]M.75 Gross and Bhattacharya, Uniting sex and eukaryote origins in an emerging oxygenic world, Biology Direct 2010, 5:53.

[*fn]M.76 Bacteria and Archaea are the two domains of bacteria, with archaea also called "extremophiles" because they live under extreme conditions (such as near hot deep ocean vents). The name "archaea" implies greater antiquity, but this is probably not the case because in fact archaea are intermediate between bacteria and eukaryotes in genetic complexity. In my view the archaea are a later development of bacteria. See Margulis & Chapman, Kingdoms and Domains (2009). The ribosomes (which make proteins) of archaea are more complex than the bacterial ribosomes, and seem to be closer to the eukaryote ribosomes.

[*fn]M.77 Two cell divisions resulting in four cells. Tetrad spores reflect this: "Envelope-enclosed spore tetrads are taken as the earliest evidence of plant life on land" dated to 470 Ma during the Ordovician.

[*fn]M.78 Osmotic or turgor pressure.

[*fn]M.79 Koonin EV: The origin and early evolution of eukaryotes in the light of phylogenomics Genome Biology 2010, 11:209.


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