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Pre-Existing Resistance

All antibiotic resistance that develops in bacteria can be traced back to mutations in bacteria that were originally susceptible to antibiotics. Explore Evolution is rather incoherent in its discussion of antibiotic resistance. It incorrectly presents antibiotic resistance as due to pre-existing coding in the bacterial population for different varieties of beta-lactamase (an enzyme that breaks down penicillin).

Explore Evolution claims:

Survival

Explore Evolution claims that some current evolutionary biologists think that mutations that result in major changes in morphology (such as the mutations in the Hox gene Ultrabithorax, which produce the four-winged fruit fly) are necessary to explain morphological evolution. Modern evolutionary biologists do not suggest mutations in the genetic toolkit must have dramatic effects (as discussed elsewhere in this critique). Explore Evolution falsely asserts that evolutionary developmental biologists doubt the role of mutation in development.

The Four-Winged Fly

The four-winged fruit fly is a classic example of how creationists misinterpret the genetic analysis of development. Developmental geneticists try to understand the role of a gene by modifying a gene and analyzing the consequences, so it is of little consequence that four winged flies would not survive in the wild. The importance of the four-winged fruit fly is that it demonstrated that a few mutations in a single gene were able to transform an entire structure.

Developmental Controls

Explore Evolution insists, contrary to the consensus of developmental biologists, that we don't really know what controls development or whether that mystery force could mutate:

Some developmental biologists now think that two other cellular features – the cytoskeleton and the cell membrane – store structural information that affecdts how the embryo develops, but there is much we do not know yet.

Mutations & New Body Plans

Explore Evolution claims:

Body Plans

Explore Evolution completely ignores studies showing that mutations in both protein coding sequences and in non-coding cis-regulatory element sequences (CREs) are responsible for changes in morphology. Explore Evolution muddies the distinction between mutations which affect protein structure and function, and mutations which affect when and where genes are turned on or off.

In its discussion of DNA and mutations, Explore Evolution asserts:

Hox & Development

In claiming that developmental processes are too integrated to allow change, Explore Evolution ignores over 10 years of research in evo-devo on the modularity of development. Evolutionary developmental biologists who study Hox genes think that mutations in the CREs of target genes for Hox genes are more likely to be more important for morphological evolution than mutations in Hox genes themselves.

Compensatory Mutations

Compensatory mutations are mutations that correct a loss of fitness due to earlier mutations. In some cases, such mutations bring their own fitness costs, but often they do not. Even when they do, it is irrelevant to the power of mutation and selection to produce novelty.

Explore Evolution claims:

"Hopeful Monsters"

The discussion of Richard Goldschmidt and his saltational model of evolution is largely copied (without credit) from an essay by "creationist anatomist" David Menton. Goldschmidt's ideas were widely criticized when first publicized, and their reputation has not improved with time. There's no particular reason to cover them in a modern biology textbook at all.

Mutation Accumulation

Evolutionary biology does not require that organisms be able to accumulate unlimited mutations. Organisms can and do accumulate large numbers of mutations. Explore Evolution is deeply misleading about the role of mutations and adaptations.

Explore Evolution claims that

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