Author: Donald L. Ewert
Response to Edward Max on TalkOrigins Immunity Article
[Editor’s Note: This is the final post in a six-part a series from microbiologist Donald L. Ewert, where he argues that the processes used by our immune system to generate antibodies are anything but “random,” and do not serve as an example of Darwinian evolution. Other posts in this rebuttal can be found at: Part One, Part Two, Part Three, and Part Four, and Part Five. In the first five posts, Dr. Ewert responded to Kathryn Applegate of the BioLogos Foundation. In this sixth post, he responds to similar arguments from Edward Max at TalkOrgins that antibody generation is “evolution in miniature.”] One of the goals of Edwards Max’s post at TalkOrigins is to refute a narrow claim of “creationists” Read More ›
Adaptive Immunity: Darwinism in Miniature or High-Tech Tinkering with Stasis?
[Editor’s Note: Today we present part five out of six in a series by microbiologist Donald L. Ewert. These posts are responding to the BioLogos Foundation’s blog where Kathryn Applegate argued that “random” processes that generate antibodies illustrate the creative power of Darwinian evolution. Previous installments of Dr. Ewert’s rebuttal can be found at the following links: Part One, Part Two, Part Three, and Part Four.] Kathryn Applegate’s main point is that if “natural” processes — which she characterizes as “random” and “blind” — can be used to generate antibodies, the same mechanisms presumably could be used to “create life over long periods of time.” The question addressed here is: Do the terms “random” and “blind” accurately describe the mechanisms Read More ›
Not By Chance: Controlling Affinity Maturation
[Editor’s Note: This is part four of a six-part series from microbiologist Donald L. Ewert responding to Kathryn Applegate, of the BioLogos Foundation, in her arguments that the vertebrate adaptive immune system illustrates the claimed creative the Darwinian mechanism. Previous parts of Ewert’s response can be found at the following links: Part One, Part Two, Part Three.] Pathogen-directed activation of the immune response The initiation of an immune response is designed so that the cellular and molecular components that are best equipped to deal with a pathogen are engaged. There are basically three response pathways. Non-protein antigens that have repeating carbohydrate units on their surface, such as are found on bacteria, can directly activate B cells. These B cell do Read More ›
Affinity Maturation and Somatic Cell Hypermutation: Intricately Controlled Processes that are Unlike Mutation and Selection
[Editor’s Note: This is part three of a six-part response from microbiologist Don Ewert to Kathryn Applegate’s arguments that the vertebrate adaptive immune system is an example of Darwinian evolution in action. Part one can be found here, and part two is here.] The second stage of B cell receptor development is initiated when a foreign protein enters our body and is detected by a circulating B cell using its cell surface antigen receptor (BCR). The BCRs that recognize these antigens improve their affinity (binding capacity) for the antigen by entering into a fine-tuning process called affinity maturation. This process ensures that highly effective antibody receptors are produced and released as cell-free antibodies into the circulation as the B cell Read More ›
Generation of Antibody Diversity is Unlike Darwinian Evolution
[Editor’s Note: This is part two of a response from microbiologist Don Ewert to arguments from BioLogos’s Kathryn Applegate that our immune system shows the creative power Darwinian evolution. Part one can be found here.] The intricate mechanism for generating antibody diversity from very few germline (existing) genes was discovered over thirty years ago. It involves shuffling gene segments and then fusing them to produce new combining sites for the antibody receptor displayed on individual B cells. How much of this process is pre-programmed and how much is random? Is this an example of the use of a “‘blind’ system to sustain and preserve life,” as Kathryn Applegate suggests? The evidence from decades of research reveals a complex network of Read More ›