What Are the Limits of Darwinism, U of T, Dr. Michael Behe

What are the Limits of Darwinism?

Michael J Behe Lehigh University

Bethlehem, PA

Disclaimer: The opinions presented here are solely my own, and do not necessarily represent the opinions of Lehigh University or any of its departments or employees.

July 1996

June 2007

“Darwinism” is a multipart theory. Some parts may be right, others wrong

•  Common descent (interesting, but trivial) – Versus

•  Natural selection (interesting, but trivial) – Versus

•  Random mutation – The critical claim of Darwinism is the sufficiency

of random mutation

G.K. Chesterton, Orthodoxy

•  “Nursery tales say that apples were golden only to refresh the forgotten moment when we found that they were green. They make rivers run with wine only to make us remember, for one wild moment, that they run with water.”

Star Trek and the Borg

http://memory-alpha.org/en/wiki/Nanotechnology

Nanotechnology: From Memory Alpha, the free Star Trek reference.

Nanotechnology is a word used to describe devices so small that the naked eye cannot see them. The Borg Collective is infamous for their use of nanotechnology to advance their goals, specifically assimilating new members and technologies with nanoprobes.

Nanotechnology

Cell (1998) 92, table of contents.

•  The Cell as a Collection of Protein Machines: Preparing the Next Generation of Molecular Biologists, Bruce Alberts

•  Polymerases and the Replisome: Machines within Machines, Tania A Baker and Stephen P Bell

•  Eukaryotic Transcription: An Interlaced Network of Transcription Factors and Chromatin-Modifying Machines, James T Kadonaga

•  Mechanical Devices of the Spliceosome: Motors, Clocks, Springs, and Things, Jonathan P Staley and Christine Guthrie

•  Molecular Movement inside the Translational Engine, Kevin S Wilson and Harry F Noller

•  The Hsp70 and Hsp60 Chaperone Machines, Bernd Bukau and Arthur L Horwich

Taylor, H.C. and Holwill, M.E.J. 1999. Axonemal dynein — a natural molecular motor. Nanotechnology 10: 237-243.

Bathybius Haeckelii

The problem of the rugged evolutionary fitness landscape. (Figure from Gavrilets,S. 2004. Fitness landscapes and the origin of species. Princeton University Press: Princeton, N.J.)

An idealized landscape

A realistic landscape

The problem of the rugged evolutionary fitness landscape. (Figure from Gavrilets,S. 2004. Fitness landscapes and the origin of species. Princeton University Press: Princeton, N.J.)

An idealized landscape

A realistic landscape

is substantially incoherent

Watson,R.A. 2006. Compositional evolution: the impact of sex, symbiosis, and modularity on the gradualist framework of evolution. MIT Press: Cambridge, Mass., p. 272.

•  In computer science we recognize the algorithmic principle described by Darwin — the linear accumulation of small changes through random variation and selection — as hill climbing, more specifically random mutation hill climbing. However, we also recognize that hill climbing is the simplest possible form of optimization and is known to work well only on a limited class of problems.

Dawkins R. 1986. The Blind Watchmaker. New York: Norton, Chapter 3, “Accumulating Small Change”, p. 43

•  “We have seen that living things are too improbable and too beautifully ‘designed’ to have come into existence by chance. How, then, did they come into existence? … by gradual, step-by-step transformations from simple beginnings…”

What is our best evidence of what Darwinian processes can actually do?

•  The best evidence we have to assess the abilities of Darwinian processes comes from studies of malaria, both in genetic changes of humans and in the parasite (Plasmodium falciparum) itself.

•  Reasons: – Detailed genetic studies – Sheer population sizes

Infection of a human by the malaria parasite, Plasmodium falciparum

The overlapping range of malaria and the sickle cell gene

The molecular structure of hemoglobin

The Amino Acid Sequences of the α and β Chains of Human Hemoglobin

V

Association of deoxygenated sickle hemoglobin

Electron micrograph of deoxygenated sickle hemoglobin fibers

Normal red blood cells Sickle red blood cells

Varieties of DNA mutations type of mutation description

Substitution switch of one kind of nucleotide for another

Deletion omission of one or more nucleotides

Insertion addition of one or more nucleotides

Inversion “flipping” of a segment of DNA double helix

Gene duplication doubling of a region of DNA containing a gene

Genome duplication doubling of the total DNA of an organism

Human genetic effects selected for resistance to malaria

Gene Mutation Adverse effects Hemoglobin HbS Sickle cell disease

alpha-thalassemia Anemia/ broken gene beta-thalassemia Anemia/ broken gene Hereditary persistence of fetal hemoglobin

Broken genetic controls

G6PD Point mutations, deletions Anemia / decrease or loss of G6PD function

Band 3 protein deletion Lethal in two copies / broken gene

Duffy antigen Point mutation Protein expression lost in red blood cells

Tishkoff,S.A., et al. 2001. Haplotype diversity and linkage disequilibrium at human G6PD: recent origin of alleles that confer malarial resistance. Science 293:455-462.

•  “… with the classic examples of sickle cell anemia and thalassemia, [G6PD deficiency] represents one of the best examples of natural selection acting on the human genome.

Much Darwinian evolution proceeds by breaking old genes

•  Disabling a gene will occur at a rate hundreds of times faster than making a specific change in a gene.

•  Very, very few of possible accessible mutations are helpful.

•  Random changes are incoherent

Random mutation in a china shop

Pelosi,L., Kuhn,L., Guetta,D., Garin,J., Geiselmann,J., Lenski,R.E., and Schneider,D. 2006. Parallel changes in global protein profiles during long-term experimental evolution in Escherichia coli. Genetics 173:1851-1869.

•  “expression of both the ribose operon and the maltose regulon decreased after 20,000 generations of experimental evolution. These changes may therefore reflect beneficial mutations in these regulons. Indeed, deletions of the rbs operon were found previously in all 12 of the evolved populations…

Woods,R., Schneider,D., Winkworth,C.L., Riley,M.A., and Lenski,R.E. 2006. Tests of parallel molecular evolution in a long-term experiment with Escherichia coli. Proc. Natl. Acad. Sci. U. S. A 103:9107-9112.

Behe, M. J., 2010 Experimental Evolution, Loss-of-function Mutations, and “The First Rule of Adaptive Evolution”. Quarterly Review of Biology 85: 1-27.

“The First Rule of Adaptive Evolution”:

Break or blunt any functional coded element whose loss would yield a net fitness gain.

A Beneficial Mutation

What observation demonstrates about random mutations

•  Of those mutations that affect an organism, about 99% are detrimental

•  Of even beneficial mutations, the great majority break genes or degrade function

Plasmodium falciparum

Chloroquine

Chloroquine-resistance in malaria requires several mutations

+

22

22 51

Powerball: The difficulty of matching several numbers

+ 22 51 17 +

Frequency of the development of antibiotic resistance of P. falciparum

•  Resistance to atovaquone arises in every third patient (about 1 in 1012 cells) (Looareesuwan,S., et al. 1996. Clinical studies of atovaquone , alone or in combination with other antimalarial drugs, for treatment of acute uncomplicated malaria in Thailand. Am. J. Trop. Med. Hyg. 54:62-66)

•  Resistance to chloroquine arises in every billionth patient (about 1 in 1020 cells) (White NJ. 2004. Antimalarial drug resistance. J Clin Invest 113:1084-1092.)

Scientific notation

This is not an argument that Darwinism cannot make complex functional systems; it is an observation that it does not.

Coyne,J.A. and Orr,H.A. 2004. Speciation. Sinauer Associates: Sunderland, Mass., p. 136.

•  The goal of theory, however, is to determine not just whether a phenomenon is theoretically possible, but whether it is biologically reasonable — that is, whether it occurs with significant frequency under conditions that are likely to occur in nature.

Protein-protein binding requires multiple interactions

Taylor, H.C. and Holwill, M.E.J. 1999. Axonemal dynein — a natural molecular motor. Nanotechnology 10: 237-243.

The depth of design in the cell

•  Because the great majority of cellular protein-protein interactions required design, it is reasonable to view the entire cell itself as a designed, integrated whole.

•  This conclusion isn’t a “God of the gaps” argument. Intelligent design isn’t a rare property of just a handful of extra-complex features of the cell. Rather, it encompasses the cellular foundation of life as a whole.

No unintelligent process helped much with malarial chloroquine-resistance, including:

•  Darwinism •  Self-organization •  Self-engineering •  Symbiosis •  Nor any as-yet-

undiscovered process

The depth of design in the animal

•  There are good, empirical reasons — based on the progress of science in the past decade in understanding embryological development at the molecular level — to think design extends at least to the level of vertebrate class.

The Goldilocks Universe

Brumfiel,G. 2006. Our Universe: Outrageous fortune. Nature 439:10-12.

•  If the number controlling the growth of the Universe since the Big Bang is just slightly too high, the Universe expands so rapidly that protons and neutrons never come close enough to bond into atoms. If it is just ever-so-slightly too small, it never expands enough, and everything remains too hot for even a single nucleus to form. Similar problems afflict the observed masses of elementary particles and the strengths of fundamental forces.

Bostrom,N. 2002. Anthropic bias: observation selection effects in science and philosophy. Routledge: New York , pp. 11-12.

•  Some philosophers and physicists take fine-tuning to be an explanandum that cries out for an explanans. Two possible explanations are usually envisioned: the design hypothesis and the ensemble hypothesis.

Fine tuning of the universe for life

•  Finely-tuned physical laws and constants •  Finely-tuned properties of chemicals •  Finely-tuned details and events

The Finely-tuned Origin of the Moon

Ward,P.D. and Brownlee,D. 2000. Rare earth: why complex life is uncommon in the universe. Copernicus: New York, p. 231, Figure legend 10.3.

•  “To produce such a massive moon, the impacting body had to be the right size, it had to impact the right point on Earth, and the impact had to have occurred at just the right time in the Earth’s growth process.”

The Origin of Life

Davies, P.C.W. 1999. The Fifth Miracle: The Search for the Origin and Meaning of Life. Simon & Schuster: New York, p. 17.

•  When I set out to write this book I was convinced that science was close to wrapping up the mystery of life’s origin. ... Having spent a year or two researching the field I am now of the opinion that there remains a huge gulf in our understanding. …This gulf in understanding is not merely ignorance about certain technical details, it is a major conceptual lacuna. ... My personal belief, for what it is worth, is that a fully satisfactory theory of the origin of life demands some radically new ideas.


•  Finely-tuned physical laws and constants •  Finely-tuned properties of chemicals •  Finely-tuned details and events


•  Finely-tuned physical laws and constants •  Finely-tuned properties of chemicals •  Finely-tuned details and events •  Finely-tuned events within biology

Laws of nature Physical constants Ratios of fundamental constants Amount of matter in the universe Speed of expansion of the universe Properties of elements such as carbon Properties of chemicals such as water Location of solar system in the galaxy Location of planet in the solar system Origin and properties of Earth/Moon Properties of biochemicals such as DNA Origin of life Cells Genetic code Multiprotein complexes Molecular machines Biological kingdoms Developmental genetic programs Integrated protein networks Phyla Cell types Classes Orders Families Genera Species Varieties Individuals Random mutations Environmental accidents


The Depth of Fine Tuning of Nature for Life on Earth



Contingency In Biology



The Edge of Random Evolution

Contingency In Biology

The intelligent design of many parts of nature for life

•  The fine-tuning of the universe in general for life and fine-tuning within biology can be viewed as all of a piece — simply the purposeful arrangement of the surprisingly many parts that science has discovered are necessary for life, both external and internal to it.

Profound questions remain unanswered

William Blake (1757–1827)

The Tiger TIGER, tiger, burning bright In the forests of the night, What immortal hand or eye Could frame thy fearful symmetry? . . .

Did He smile His work to see?

Did He who made the lamb make thee?

All the World’s a Stage

http://behe.uncommondescent.com/

What Are the Limits of Darwinism, U of T, Dr. Michael Behe

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