The Darwinian Basis of the Prokaryote-to-Eukaryote Transition Collapses

The question of the evolution of eukaryotic cells from prokaryotic ones has long been a topic of heated discussion in the scientific literature. It is generally thought that eukaryotes arose by some prokaryotic cells being engulfed and assimilated by other prokaryotic cells. Called endosymbiotic theory, there is some empirical basis for this. For example, mitochondria contain a single circular genome, carry out transcription and translation within its compartment, use bacteria-like enzymes/components, and replicate independently of host cell division and in a manner akin to bacterial binary fission. Despite such evidence, however, when assessing the causal sufficiency of unguided processes, they — predictably — come up short. After all, it is all-too-easy to lapse into a long-discredited Lamarckian “inheritance-of-acquired-characteristics” mentality. It 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 ›

Who or What Plays the Music of DNA?

As I was driving in to work, the local NPR station had on an interview with a guy who’s involved with gathering billions of seeds of various plant varieties into a “doomsday vault.” It is on a remote Norwegian island and intended as a precaution against the presumed devastations of global warming. There were few surprises in the conversation — the grim mood was well suited to the NPR target audience, which eats this stuff up — apart from one rather interesting question from a listener. The guest, Cary Fowler of the Global Crop Diversity Trust, was asked why his group bothers with seeds. In the future, won’t we be able to reconstitute life from the digital code of DNA? Read More ›

Recapping Responses to Nature‘s Evolution Evangelism Packet

I’ve received quite a bit of positive feedback about the responses to the Nature 15 Evolutionary Gems packet that we’ve been responding to since last summer. As a recap of this series, below are links to the 9 parts responding to what I’ve affectionately called “Nature‘s Evolution-Evangelism Packet.” Also, we’ve compiled the responses into a single PDF that can be used for educational purposes: Part 1: Evaluating Nature’s 2009 “15 Evolutionary Gems” Darwin-Evangelism Kit Part 2: Nature’s Microevolutionary Gems Part 1: Lizards, Fish, Snakes, and Clams Part 3: Nature’s Microevolutionary Gems Part 2: Bird-Sized Evolutionary Change Part 4: Nature’s Microevolutionary Gems Part 3: Flea and Guppy-Sized Evolutionary Change Part 5: Nature’s “Gems”: Microevolution Meets Microevolution Part 6: Evolutionary “Gems” or Read More ›