by Richard Peachey What are "vestigial organs"? "Vestigial" or "rudimentary" organs are biological structures that have no function. In The Descent of Man, Charles Darwin listed such human structures as wisdom teeth, the appendix, and the coccyx ("tailbone") as "rudimentary organs" (Scadding 173f.). In his earlier book, The Origin of
by Richard Peachey Peripatus is an organism classified within the phylum Onychophora, a group known as "velvet worms" or "onychophorans" (meaning "claw-bearers"). These animals live mostly in humid forests, especially in the tropics. They hide by day under rotting logs and in leaf litter, and hunt for prey at night.
by Richard Peachey What is Sickle-Cell Anemia? Sickle-cell anemia is a genetic disease common to persons of West and Central African ancestry. It is characterized by severe anemia with symptoms of pallor, muscle cramps, weakness, and susceptibility to fatigue. Additional symptoms include heart enlargement, brain cell atrophy, and severe pain
With a special Appendix: University of Chicago evolutionist Jerry Coyne on his discovery of the many flaws in this "icon of evolution"! (following the conclusion of this article) by Richard Peachey IMPORTANT NOTE: The argumentation in the article below requires updating in light of new experimental work by lepidopterist Michael
Major Twentieth Century Theories of Evolution: The Neo-Darwinian Synthesis and Punctuated Equilibrium
by Richard Peachey The two modern theories differ over the tempo (timing) and mode (mechanism) of evolution. Natural selection is of primary importance for Neo-Darwinists, but not for those who hold to Punctuated Equilibrium. The two views also disagree on the relationship of macroevolution to microevolution. 1. The Neo-Darwinian Synthesis
by Richard Peachey The French scientist Jean-Baptiste de Lamarck (1744-1829) is noted for two "laws" which summarize his evolutionary thought: (1) The Law of Use and Disuse — The parts of an organism's body that are used become more developed; parts that are not used become smaller and may disappear.
by Richard Peachey Both Lamarck and Darwin viewed evolution as slow and gradual. (Neither believed in "fixity of species.") But their theories assigned different roles to the organism, and to the environment. 1. Jean-Baptiste de Lamarck (1744-1829) Lamarck was a French scientist who, after the French Revolution, was appointed to be
With a special Appendix: Harvard paleontologist Stephen Jay Gould on the inappropriate textbook use of the giraffe to introduce students to evolutionary theories! (after the conclusion of this article) by Richard Peachey High-school biology texts regularly present Darwin’s theory of evolution in contrast with Lamarck’s earlier explanation, and the organism
Introduced by Richard Peachey The arguments summarized below are taken from W. R. Bird, The Origin of Species Revisited (New York: Philosophical Library, 1987), Vol. 2, pp. 104-106. When the Supreme Court of the United States reviewed Louisiana's "Act for Balanced Treatment of Creation-Science and Evolution," Bird was the lawyer
by Richard Peachey 1. INTRODUCTION: THE FAMOUS FINCHES The Galápagos Islands are home to a famous group of birds called "Darwin's finches." Most taxonomists view these finches as belonging to thirteen separate species within four (or three) genera of a single family (or subfamily). All of the Galápagos finches are