Fallacy?

Cherry-picking

The evidence that fits is shown, and the evidence that doesn't is left out.

Also called: Selective evidence · Quote mining

The test

What does the full set of evidence show? Were the contrary results mentioned?

Textbooks and popular books must choose examples, and choosing is not cheating. The fallacy is in letting a hand-picked set stand in for the whole, when the whole would tell a different story.

Critics of evolution have a particular version to watch for: the quotation lifted from its context. A biologist's admission that something is unexplained is honest and worth noting. Presenting it as a concession that the theory has failed, when the author went on to defend it, is not.

Seen on both sides

In mainstream arguments
It would be cherry-picking to illustrate embryo similarity with drawings that showed the matching stages and smoothed away the differences.
In critical arguments
It would be cherry-picking to quote a scientist's frank admission of a problem, and leave out the answer they proposed in the next paragraph.
Not a fallacy when

A typical or representative example is chosen to illustrate a pattern that has been shown on the full data.

Diagnosed on this site

  • Claim № 2.01 · Transitional seriesPossible
    In evidence: Tiktaalik: a predicted find

    The successful prediction is widely retold. The Zachełmie trackways, which complicate it, are rarely mentioned alongside it in textbooks.

  • Claim № 2.01 · Transitional seriesPossible
    In evidence: The horse series

    Older textbook displays showed a straight line from small to large horses. The record is now read as a branching bush; the straight line selected the fossils that fit it.

  • Claim № 3.02 · The tree of lifePossible
    In the claim as taught

    “Generally agree” summarises the agreeing results. It leaves out the conflict that Dávalos and colleagues describe as pervasive as datasets grow.

  • Claim № 3.03 · Embryos & developmentClear case
    In evidence: Haeckel's drawings

    The drawings selected and idealised the similarities, and smoothed away the differences (Richardson et al. 1997). Their use in textbooks for decades afterwards repeated the selection.

Further reading

  1. Richardson MK, et al. “There is no highly conserved embryonic stage in the vertebrates.” Anatomy and Embryology 196:91–106 (1997).