Helvetios
Heathen Sapiens
The Journal of Cladistics, born from the Willi Hennig Society, has about 600 subscribers. Its February 2016 issue was published recently and included this controversial editorial. For those without a biology background, here is what they're talking about:
1. Our journal only accepts papers that use parsimony to generate trees. Trees generated by other methods are not useful and only clutter the page. You can still include one, but only if accompanied by a parsimony tree.
2. We have philosophical reasons to believe that other methods are inherently inferior, including those recently developed. If you want to use another method instead, you must provide a philosophical justification for (a) your decision not to use parsimony, and (b) any results that do not match those generated by parsimony.
4. Our journal has a high impact factor so we must be doing something right, and that makes this okay. (an impact factor is a ratio of citations to recent articles in the journal, to quantify the influence that journal's articles have on future research)
Naturally, the scientific community erupted in criticism. Citing one's impact factor, philosophical reasoning and no references published later than 1983 are some fairly obvious red flags that the Cladistics editorial decision is unscientific and grounded in dogma. (Notice that one of their references is to Willi Hennig himself, whom they look up to, but that isn't a reason to cite something they said over 30 years ago as if it's still true today.)
Since this is the internet, scientists took to Twitter under the tag #parsimonygate to debate, call for a boycott and/or revision of the original editorial, and make jokes. Blog posts, articles, and whatever passes for discussion on Twitter are still making the rounds. Enjoy the show!
- Cladistics is a method of classifying biological organisms, in which the organisms are classified based on what we call shared derived characteristics. That is, characteristics that the organisms inherited from their ancestors. For example, if we wish to classify humans, mice and chimpanzees, all of these animals would have a common ancestor because they are all mammals that grow hair and produce milk. However, humans and chimpanzees have a shared derived characteristic that the mice don't -- opposable thumbs -- and therefore they are more closely related to each other. The field of cladistics has given biologists a bunch of vocabulary to describe the evolutionary trees they construct, which enables them to represent the trees more clearly.
- Parsimony is a way of finding the simplest path from A to B. In biology, the most parsimonious evolutionary tree is the one that requires the fewest changes to get from a common ancestor (graphically represented as the 'root' of the tree) to all of the descendants. Going back to the previous example, the most parsimonious tree would group humans and chimpanzees more closely together than humans and mice, because which is more likely: that opposable thumbs evolved once and were inherited by both humans and chimps, or that opposable thumbs evolved independently in two separate species? Parsimony assumes that the trait only evolved once.
- Advancements have been made since parsimony was the gold standard in constructing trees. Statistical analysis such as Bayesian methods, Monte Carlo, and maximum likelihood are more useful in many areas, although parsimony still has 'use cases' where it is still the best choice.
1. Our journal only accepts papers that use parsimony to generate trees. Trees generated by other methods are not useful and only clutter the page. You can still include one, but only if accompanied by a parsimony tree.
2. We have philosophical reasons to believe that other methods are inherently inferior, including those recently developed. If you want to use another method instead, you must provide a philosophical justification for (a) your decision not to use parsimony, and (b) any results that do not match those generated by parsimony.
4. Our journal has a high impact factor so we must be doing something right, and that makes this okay. (an impact factor is a ratio of citations to recent articles in the journal, to quantify the influence that journal's articles have on future research)
Naturally, the scientific community erupted in criticism. Citing one's impact factor, philosophical reasoning and no references published later than 1983 are some fairly obvious red flags that the Cladistics editorial decision is unscientific and grounded in dogma. (Notice that one of their references is to Willi Hennig himself, whom they look up to, but that isn't a reason to cite something they said over 30 years ago as if it's still true today.)
Since this is the internet, scientists took to Twitter under the tag #parsimonygate to debate, call for a boycott and/or revision of the original editorial, and make jokes. Blog posts, articles, and whatever passes for discussion on Twitter are still making the rounds. Enjoy the show!
