Q. So wtf is a cladist?
A. One who trudges in the footsteps of Willi Hennig to accept Cladistics aka phylogenetic systematics as a useful [true?] explanation of biological diversity which so intrigues those who pay attention to the natural world. In the 1980s, cladistics was really annoying to traditional classifiers, taxonomists and namers-of-parts because it forced them to reconsider their certainties. Hennig and the Cladists [great name for a rock band] wanted to bring Evolution's "descent with modification" front and centre. A Clade was / is all the descendant members of a single branch of the tree of life. In particular cladists frowned on paraphyletic groupings: those which shared some [superficial?] similarities. Or relicts ["waste-baskets"] of taxa which had been 'left behind' when some of their number underwent an adaptive radiation into endless forms most beautiful.
- Clades are fractal: Family Hominidae [Gorilla, Homo, Pan, Pongo] is a clade; Order Primates is a clade; Class Mammalia is a clade.
- When I was in school, one of the standard, agreed, mammalian orders was "Insectivora" which included small, scurrying, nocturnal mammals that ate insects. Mammals arose in the Jurassic 225mya as small, scurrying, nocturnal mammals that ate insects and managed to avoid getting stepped upon by dinosaurs. When the dinosaurs were Offed, mammals radiated spectacularly into the vacant niches and beyond. Those left behind doing the same-old same-old were not a clade because that would exclude co-descendant aardvarks, bats, camels, dogs, elephants.
- Order Artiodactyla [antelopes, bovines, camels, deer, llamas, pigs] ain't a clade either . . . unless you include whales and dolphins [Dan, Des, Prev]
- Class Reptilia [absolutely standard when I was in school] isn't a clade unless Class Aves [birbs] and Class Mammalia are included.
- Fish aren't a clade either because we-the-mammals [and sundry other non-fish] are descended from fish; but don't have scales and swim-bladders.
That ⬤ last bullet has attracted the most attention. Notably from the competitive-clever-clogs podcast No Such Thing as a Fish. For the past 12 years, the undoubtedly smart and articulate QI Elves have been riffing on the Interesting bits-n-bobs which a) they've uncovered in their extensive reading but which b) aren't Quite Interesting enough to make the to-be-broadcast cut. It's madly popular. 30 minutes of it [ever] is plenty.
A more valuable [profound? subtle?] take on the Fish idea is the love-story in Why Fish Don't Exist (2020) by Lulu Miller. Miller grew up in a Double Prof [♀ arts ♂ science] home in Newton, suburban Boston. Her father cut her no slack growing up: no tooth fairy; no Santa there. Instead a rather nihilistic assertion that Lulu [and the Dad, and we all] was a fleck of spittle destined to evaporate to nothingness through the heedless grinding of physical entropy. She took that message on board and tried to top herself [pills] as a teen. Thanks, Dad!
A bit later she came across a man, born in 1851, who seemed to have fought against the powers of darkness and chaos to shine an enduring light on the way the world was ordered. David Starr Jordan suffered desperate loss: his beloved older brother [typhus], his first wife [pneumonia] his 9 y.o. daughter [scarlatina] his life's work [twice: once by fire and once in the San Francisco earthquake of 1906]. Jordan concentrated on recording the diversity of fish which he collected, considered, labelled and catalogued in quantity: Maybe 20% of all the species of fish known to science were described by Jordan and his students. Oh, and he was the founding President of Stanford University.
Miller spent the next few years in the archives "as I flipped though thousands of pages, remnants of David’s skin entering my nostrils." reading books, pamphlets, diaries and papers by and about David Starr Jordan, his science and shenanigans. Somewhere along her journey of biographical discovery, Miller was introduced to Cladistics and uses this, anachronistically, to add the non-existence of "Fish" to the list of Jordan's losses. Her own journey of self-discovery, not without hardship and loss, comes out right in the end with less of the existential angst and more of the wife and two kids.
What I also admire, in the polarized, judgmental, self-righteous times in which we live, is that Miller considers Jordan warts-and-all. He made way above average contributions to science despite taking many tonks from an uncaring Universe; he is an Icon of Grit.
He was also a born-again evangelical eugenicist who campaigned far and wide, long and hard, to rid the world of people whom he and his white middle-class certainists deemed unfit. Miller makes a coherent case that this sort of thing is not only cruel and unjust, but also self-defeating in a Darwinian sense. We have no idea which people are going to be most useful during a proper-hard pandemic; or the zombie apocalypse; or an invasion from the Planet Zorg. It is vanishingly unlikely to be Stanford Admin, Multinational CEOs or mid-range financial traders. People are multi-faceted! People can be repellent in their habits and beliefs and still do good science, make great art, write like an angel.
~~~~~~~
PS. I finished the book, I was uplifted. I went back to my usual restless scanning of the internet. And whoa I found myself reading a series of essays about "Born Free & Equal" on the Scotus blog, by a Republican-leaning Law Professor. One essay is on Buck vs Bell which made it to the US Supreme Court in 1927 when eugenics was Hot. Carrie Buck was sterilized because some folk claimed she was 'feebleminded' and 'promiscuous' and . . . therefore her future children would be a threat to society. In 1927 SCJ Oliver Wendell Holmes famously quipped "Three generations of imbeciles are enough" before sealing her fate withn abdominal surgery. In 2026, Professor Calabresi counterquipped "Three generations of Holmes Lectures [at Harvard Law School] are enough." Yes yes very quippy and also very black & white unsubtle and Cancel Culture: unlike Lulu Miller. See also Skinner v Oklahoma for how eugenics reasoning will come for you next. Martin Niemöller: Zuerst kamen sie für die Kommunisten und ich sprach nicht . . . etc.
The day before, I'd been harking to a Mindscape Podcast [MultiPrev] in which poor Sean Carroll felt obliged again to hash out Free & Equal Free Will with Greg Caruso. [Free Will bloboprevs] For current purposes, you don't need to listen to 80 mins of clever philosophical jousting. Just click on the transcript and CTRL-F for 'felon' or '0:44:58.2 GC' to see how Punisher legislators and "three strikes and out" can force a man into a life-sentence for crimes that don't seem to be liable to cause wide-spread societal collapse . . . a bit of shop-lifting.








