Fellow paleontologists, I am delighted to introduce David Jablonski this evening. For over thirty years, Dave has been one of the most influential scientists in our midst. I’ve been given only five minutes, so I can’t do justice to the wide range of his contributions on topics as diverse as: the effect of larval ecology on evolution; causes of the latitudinal diversity gradient; determinants and consequences of geographic range size; environmental and geographic patterns in the origin and fate of evolutionary novelties; the biology and evolutionary impact of mass extinctions; species selection; and the fundamental truth that macroevolution is not merely an extrapolation of microevolution to larger temporal scales and taxonomic levels. Let me instead mention just a few favorite examples:

(1) His 1986 paper on background and mass extinction regimes inspired scores of studies on whether and how macroevolutionary “rules” of survival change depending on the intensity and extent of perturbations to the biosphere. This work also demonstrates the importance of hierarchical thinking in paleobiology. For example, during background times in the Late Cretaceous, survival of molluscan genera could be predicted to some extent from properties of their constituent species. During the K/Pg event, however, it appeared to be the properties of genera as genera that mattered.

(2) A related paper a year later, importing standard approaches from quantitative genetics, demonstrated heritability of a species-level trait—geographic range—in marine mollusks, and therefore argued in favor of the very real potential for evolution by species sorting.

(3) Dave’s group recently showed that the geographic ranges of living bivalve species are determined not so much by the breadth of their thermal tolerances, but instead by how geographically widespread their preferred temperatures are. This work is an important element in the drive to make sense of the wide variation in geographic range seen today and in the fossil record.

(4) In a study with John Finarelli, Dave showed that morphologically defined, Linnaean genera of mollusks and mammals are largely monophyletic and have coherent macroecological properties (like geographic range and body size), when judged by their concordance with clades present in molecular phylogenies. Such genera therefore are valid and meaningful evolutionary units for a wide range of analyses, both paleontological and neontological.

If you’ve read even a handful of his papers, you’ll know that Dave excels at rhetoric, in the positive sense of crafting an argument. His turn of phrase is captivating—think of some of the items that have entered our vocabulary: “the alternation of macroevolutionary regimes”; “the Lazarus effect”; and “dead clade walking.” I’ll ask him to read a manuscript written in my just-the-facts-ma’am style, he’ll critique the science, but then provide crucial insights into how to win the reader over. I’ve succumbed in quite a few friendly debates with Dave, in no small part because he maintains an astonishing command of the scientific literature and the history of ideas. You’ve no doubt seen his bibliographies, which are almost as long as the papers themselves. But there’s no perfunctory citation to be found. Everything he reads is digested, analyzed, internalized, and synthesized into a coherent and persuasive world view of macroevolution.

Dave has earned accolades, but he’s too wrapped up in moving the field forward to stop and bask in the glory. For example, when I went to his tidy and sparsely appointed office to congratulate him upon his election to the National Academy of Sciences, he made it clear that he didn’t just want to accept the recognition—he wanted to do useful work for the Academy. The caseload of manuscripts he has handled on the PNAS editorial board (many of which have made their way down the hallway to my desk) shows that he meant what he said.

I’d like to say a bit about Dave as a colleague and a mensch. By my count we have been on some thirty student committees together. One of his favorite adages is that every PhD committee needs three kinds of members: a bad cop; a cheerleader; and a shoulder to cry on. He manages to excel in the last two roles while not relenting on his high scientific standards. When I was department chair, it is for exactly this reason that I asked him to lead a junior faculty advisory committee—I wanted someone with a sharp mind and a soft heart.

On the personal side, Dave’s passion for food, literature, music, and life itself, are legendary, and his tastes are incredibly broad. I once found myself with an unexpected day off in Manhattan and called Dave at his office: “Dave, I’m at the corner of 10th and Broadway; what should I do?” After exclaiming, “You lucky dog!” he rattled off the names and locations of the best coffeehouse, bookshop, and Thai restaurant in the neighborhood. As usual, his recommendations were spot on.

Finally, Dave has been a tireless advocate for and servant to the field of paleontology. As Steve Holland mentioned in his Presidential Address last year, many of us feel the frustration that our biological colleagues don’t quite understand what we do and why. Dave has been a great ambassador, educating biologists—not to mention non-scientists—on the major lessons the fossil record teaches about how evolution works; and clarifying for paleontologists the relevance of areas such as developmental biology.

Members of the Society and guests, it is an honor and a pleasure to present the recipient of the 2017 Paleontological Society Medal, David Jablonski.

October 22, 2017