3 ms·

No actually it's not a fallacy, taken from your own link: "Embryos do reflect the course of evolution"

thaumasiotes 7y ago
Try quoting more than the first half of a sentence intended to placate people who learned to believe in the fallacy. the shortcomings of the theory had been recognized by the early 20th century, and it had been relegated to "biological mythology" by the mid-20th century The Haeckelian form of recapitulation theory is considered defunct. the Biogenetic Law was abandoned, and its fall freed scientists to appreciate the full range of embryonic changes that evolution can produce
- tabtab 7y ago
  The cited book is 1963. I'd feel more comfortable with something more recent. It seems to be a debate of degree. Earlier forms do tend to be preserved in the embryo, but it's only a tendency, not a "rule".
  - jhedwards 7y ago
    Mentioned in my other comment above: https://en.wikipedia.org/wiki/Ontogeny_and_Phylogeny_(book) https://en.wikipedia.org/wiki/Ontogeny_and_Phylogeny_(book)
  - thaumasiotes 7y ago
    >> it had been relegated to "biological mythology" by the mid-20th century > The cited book is [from] 1963. Sorry, when would you expect a citation for "it had been relegated to 'biological mythology' by the mid-20th century" to date from?
    - tabtab 7y ago
      As a hard and fast rule, yes, it has been deprecated, but not as a tendency or influence.
- andrewflnr 7y ago
  AFAICT the comment you first responded to is consistent with the modern form of the idea. There's no reason to assume they were specifically thinking of Haeckellian recapitulation.
- jshevek 7y ago
  It is a fact that many embryos go through stages similar to portions of that organism's evolutionary history. This fact alone justifies the cautious phrasing of the great-grandparents comment, in my opinion. Since this fact is also indicated in the excerpted quote you criticize, I think the quote served it purpose. (Though I would agree the 'reflect' can be misinterpreted).

Try quoting more than the first half of a sentence intended to placate people who learned to believe in the fallacy. the shortcomings of the theory had been recognized by the early 20th century, and it had been relegated to "biological mythology" by the mid-20th century The Haeckelian form of recapitulation theory is considered defunct. the Biogenetic Law was abandoned, and its fall freed scientists to appreciate the full range of embryonic changes that evolution can produce

tabtab 7y ago
The cited book is 1963. I'd feel more comfortable with something more recent. It seems to be a debate of degree. Earlier forms do tend to be preserved in the embryo, but it's only a tendency, not a "rule".
- jhedwards 7y ago
  Mentioned in my other comment above: https://en.wikipedia.org/wiki/Ontogeny_and_Phylogeny_(book) https://en.wikipedia.org/wiki/Ontogeny_and_Phylogeny_(book)
- thaumasiotes 7y ago
  >> it had been relegated to "biological mythology" by the mid-20th century > The cited book is [from] 1963. Sorry, when would you expect a citation for "it had been relegated to 'biological mythology' by the mid-20th century" to date from?
  - tabtab 7y ago
    As a hard and fast rule, yes, it has been deprecated, but not as a tendency or influence.
andrewflnr 7y ago
AFAICT the comment you first responded to is consistent with the modern form of the idea. There's no reason to assume they were specifically thinking of Haeckellian recapitulation.
jshevek 7y ago
It is a fact that many embryos go through stages similar to portions of that organism's evolutionary history. This fact alone justifies the cautious phrasing of the great-grandparents comment, in my opinion. Since this fact is also indicated in the excerpted quote you criticize, I think the quote served it purpose. (Though I would agree the 'reflect' can be misinterpreted).