The positive case of systematic design

Photo: Mexican free-tailed bats, by dizfunkshinal, CC BY 2.0 via Wikimedia Commons.

Editor’s Note: We are delighted to present a series by geologist Casey Luskin on “The Positive Case for Intelligent Design”. This is the fifth entry in the series, an edited excerpt from the new book The Complete Guide to Science and Faith: Exploring the Ultimate Questions About Life and the Cosmos. Find the complete series to date here.

Observation (from previous studies): Intelligent agents reuse functional components in different systems (for example, the wheels of cars and planes, or the keyboards of cell phones and computers):

  • “An intelligent cause can reuse or redeploy the same module in different systems, without there necessarily being a hardware or physical connection between these systems. Even more simply, intelligent causes can independently generate identical patterns.1
  • “According to this [evolutionary] argument, the Darwinian principle of common ancestry predicts such common characteristics, justifying the theory of evolution. A problem with this line of argument is that people recognized common characteristics long before Darwin, and they attributed them to a common design. Just as we find certain features that crop up again and again in the realm of human technology (for example, the wheels and axles of wagons, buggies, and cars), we can also expect a clever designer to reuse good design ideas in a variety of situations where they work.”2
  • “[I]If different forms of life have been intelligently designed, with a mosaic of characteristics, some of which they have in common with certain organisms and some of which they have in common with different organisms, then one would expect that “phylogenetic” analyzes generate contradictory trees depending on which character was chosen. Indeed, phylogenetic analyzes of different traits present in several human-designed technological objects have been shown to generate precisely such contradictory trees.3

Hypothesis (prediction): Genes and other functional parts will be reused in different, unrelated organisms in a pattern that does not need to fit a “tree” or nested hierarchy.

Experience (data): Similar parts have been found reused in very different organisms where even evolutionists believe the common ancestor did not have the part in question. Examples include similar genes controlling eye or limb growth in different organisms whose putative common ancestors are not thought to have had such eye or limb shapes.4 There are many examples of extreme convergent genetic evolution, including similar genes used in whales and bats for echolocation.5 Genes and functional parts are often not distributed in a “tree” pattern or nested hierarchy predicted by common ancestry, but instead show reuse in a non-nested pattern.6 A popular scientific article acknowledges:

Incongruity between phylogenies derived from morphological and molecular analyses, and between trees based on different subsets of molecular sequences has become pervasive as datasets have expanded rapidly in both characters and species. … phylogenetic conflicts are common and often the norm rather than the exception.7

Conclusion: The common design prevails throughout life. The reuse of highly similar and complex parts in very different organisms in non-tree models is best explained by the action of an intelligent agent.

Following“The positive case of design in genetics”


  1. Paul Nelson and Jonathan Wells, “Homology in Biology”, Darwinism, design and public education303-322.
  2. William A. Dembski and Jonathan Witt, Uncensored Smart Design: An Easy-to-Understand Guide to Controversy (Downers Grove, Ill.: InterVarsity, 2010), 85.
  3. Günter Bechly and Stephen C. Meyer, “The Fossil Record and Universal Common Ancestry”, Theistic Evolution: A Scientific, Philosophical, and Theological Critique, ed. JP Moreland, Stephen C. Meyer, Christopher Shaw, Ann K. Gauger and Wayne Grudem (Wheaton, IL: Crossway, 2017), 331-361.
  4. R. Quiring et al., “Homology of the eyeless gene of Drosophila to little eye in mice and Aniridia in man”, Science 265 (August 5, 1994), 785-789; DB Wake et al., “Homoplasy: from model detection to determination of the process and mechanism of evolution”, Science 331 (2011 Feb 25), 1032-1035.
  5. PENNSYLVANIA. Christin et al., “Causes and evolutionary significance of genetic convergence”, Trends in Genetics 26 (2010), 400-405; Y. Li et al., “The auditory gene Prestin unites bats and whales in echolocation”, Current biology 20 (January 2010), R55-R56; G. Jones, “Molecular Evolution: Gene Convergence in Echolocating Mammals,” Current biology 20 (January 2010), R62-R64.
  6. For example, see W. Ford Doolittle, “Phylogenetic Classification and the Universal Tree,” Science 284 (June 25, 1999), 2124-2128; W. Ford Doolittle, “Uprooting the Tree of Life,” American Scientist (February 2000), 90-95; Arcady R. Mushegian et al., “Large-scale taxonomic profiling of eukaryotic model organisms: comparison of orthologous proteins encoded by human, fly, nematode, and yeast genomes”, Genome research 8 (1998), 590-598; James H. Degnan and Noah A. Rosenberg, “Genetic Tree Mismatch, Phylogenetic Inference, and Multispecies Coalescing,” Trends in Ecology and Evolution 24 (2009), 332-340; Eric Bapteste et al., “Networks: developing evolutionary thinking”, Trends in Genetics 29 (2013 Aug), 439-441; Graham Lawton, “Why Darwin Got the Tree of Life Wrong”, new scientist (January 21, 2009), 34-39; Trisha Gura, “Bones, Molecules or Both? » Nature 406 (July 20, 2000), 230-233; Anna Marie A. Aguinaldo et al., “Evidence for a clade of nematodes, arthropods, and other moulting animals”, Nature 387 (May 29, 1997), 489-493; Erich D. Jarvis et al., “Whole-genome analyzes resolve early branches of modern bird tree of life”, Science 346 (12 December 2014), 1320-1331; Ewen Callaway, “Flock of Geneticists Redesigns Bird Family Tree”, Nature 516 (11 December 2014), 297; Emma C. Teeling and S. Blair Hedges, “Making the Impossible Possible: Rooting the Tree of Placental Mammals,” Molecular biology and evolution (2013); James E. Tarver et al., “Placental mammalian interrelationships and the limits of phylogenetic inference”, Biology and evolution of the genome 8 (2006), 330-344; Jeffrey H. Schwartz and Bruno Maresca, “Do Molecular Clocks Work at All? A critique of molecular systematics, Biological theory 1 (2006 Dec), 357-371; Maximilian J. Telford, “Fighting for a Comb”, Nature 529 (January 21, 2016), 286; Antonis Rokas; “My older sister is a nut? » Science 342 (13 December 2013), 1327-1329; Benjamin J. Liebeskind et al., “Complex homology and evolution of nervous systems”, Trends in Ecology and Evolution 31 (2016 Feb), 127-135; Amy Maxmen, “Evolution: You’re Drunk: DNA Studies Flip the Complexity Scale”, Nautilus 9 (January 30, 2014), (accessed October 28, 2020); David A. Legg et al., “The Cambrian bivalve arthropod reveals the origin of arthrodization”, Proceedings of the Royal Society B 279 (2012), 4699-4704; Mark S. Springer et al., “Endemic African Mammals Shake the Phylogenetic Tree”, Nature 388 (July 3, 1997), 61-64; William J. Murphy et al., “Molecular Phylogenetics and Origins of Placental Mammals,” Nature 409 (2001 Feb. 1), 614-618; F. Keith Barker et al., “Phylogeny and diversification of the greatest avian radiation”, Proceedings of the National Academy of Sciences of the United States 101 (2004 July 27), 11040-11045; Rodolphe Tabuce et al., “Early Tertiary mammals from North Africa reinforce the molecular clade of Afrotheria”, Proceedings of the Royal Society B 274 (2007), 1159-1166.
  7. Liliana M. Dávalos et al., “Understanding phylogenetic incongruence: lessons from phyllostomid bats,” Cambridge Philosophical Society Biological Journals 87 (2012), 991-1024.

Casey Luskins

Associate DirectorCenter for Science and Culture

Casey Luskin is a geologist and lawyer with degrees in science and law, giving him expertise in both the scientific and legal dimensions of the evolutionary debate. He received his Ph.D. in Geology from the University of Johannesburg, as well as BS and MS degrees in Earth Sciences from the University of California, San Diego, where he studied evolution extensively at the university and university levels. undergraduate. He holds a law degree from the University of San Diego, where he focused his studies on First Amendment law, education law and environmental law.



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