2026/01/01 by Susan Kennedy, Henrik Krehenwinkel · 1 voice
Biochemistry, Genetics and Molecular Biology · Earth and Planetary Sciences · Agricultural and Biological Sciences · #Spider Taxonomy and Behavior Studies #Subterranean biodiversity and taxonomy #Animal Behavior and Reproduction
paper · pdf · doi:10.1111/mec.70232
If your work involves ecology, evolution or conservation biology, it's quite likely that you've heard of Professor Rosemary Gillespie of the University of California, Berkeley. But if you're working in the field of island biogeography, it's almost certain you know her. Rosie is a brilliant and highly prolific scientist, uniting a rare combination of big-picture thinking and mastery of details. Her contributions to the literature include several hundred research papers, numerous reviews, book chapters and several influential books (e.g., Gillespie and Clague 2009). These publications span an impressive diversity of topics and include many groundbreaking findings and textbook examples taught in biogeography classes around the world. Rosie's work has encompassed multiple groups of organisms and many different island ecosystems, but her true love undeniably lies in the Hawaiian Islands and their diverse spider communities. Hawaii is one of the most isolated and remote places on Earth. This isolation, coupled with the archipelago's topographic and climatic diversity, gave rise to famous adaptive radiations, for example, the honeycreeper birds (Lerner et al. 2011) and silversword plants (Carlquist 1965); and, thanks to Rosie's work, spiders have joined these ranks. Rosie discovered the adaptive radiation of Hawaiian long-jawed orbweaver spiders (Tetragnatha spp.), a genus that occurs globally and tends to have a very conserved morphology and behaviour. In stark contrast to most Tetragnatha species, Rosie found that the Hawaiian species—roughly 60 of them known, and perhaps more yet undiscovered—exhibit highly diverse morphologies, colorations and ecological affinities. Even more exciting, she found strong evidence for repeated evolution of ecomorphs—highly stereotyped morphologies associated with specific microhabitats—that occurred in parallel on each island in the Spiny Leg clade of these spiders (Gillespie 2004). Other famous examples from Hawaii are the repeated evolution of orb web morphologies in the web-building Tetragnatha (Blackledge and Gillespie 2004) and camouflage colour morphs (likely an adaptation to predation by birds) in stick spiders (genus Ariamnes; Gillespie et al. 2018). The repeated emergence of similar traits in response to the same selective pressures offers particularly strong evidence of evolutionary processes (Jones et al. 2012)—that is, if you understand the theory of evolution. But much to Rosie's dismay, her stick spider example was misinterpreted by the Institute for Creation Research, who conflated ‘predictable’ with ‘purposeful’ evolution, as a compelling example of intelligent design. Though this was not the kind of exposure she had been hoping for, the study undeniably had a wider reach than just the scientific community! But spiders were only the beginning. Hawaii's potential as a ‘natural laboratory’ is unsurpassed, and Rosie has used it to full advantage to study the origins of biodiversity and the interplay between ecology and evolution (Graham et al. 2023; Lim et al. 2022; Rominger et al. 2016). Hawaii's geography makes it a unique and highly valuable study system. The islands emerged due to the migration of the Pacific Continental plate over a volcanic hotspot and form a natural chronosequence that gets progressively older from southeast (the youngest, the ‘Big Island’) to northwest (the oldest, Kaua'i), with each island harbouring very similar ecosystems. The chronosequence thus creates a space-for-time substitution in which ecological and evolutionary processes of community assembly can be studied at different snapshots in time (Shaw and Gillespie 2016). Making use of this unique system, Rosie has devoted her career to studying community assembly. Considering the broad relevance of Rosie's research, it's not surprising that she's very successful in acquiring competitive grants and has led numerous large-scale projects. The significance of Rosie's work is also reflected in the many prestigious awards that have been bestowed upon her. Among several others, these include the Society for Biogeography's Alfred Russell Wallace Award, which recognises ‘an outstanding current research record and impact by an eminent scholar’, and her induction into the American Academy of Arts and Sciences. The impact of Rosie's research is not only mirrored in her impressive publication record and awards, but also in numerous invited and plenary lectures. Rosie truly understands how to communicate her research and its significance to diverse audiences. Her talks are engaging and her enthusiasm contagious. In these talks, she strongly advocates for the conservation of not just species, but whole ecosystems. Hawaii, and island systems in general, are highly vulnerable to biodiversity loss: They harbour a disproportionate amount of Earth's total biodiversity, yet are also exceptionally sensitive to threats such as habitat destruction, overharvesting, biological invasion and climate change. Rosie has a real gift for communicating this information and the urgency of protecting unique island ecosystems. Her presentations are inspiring to students, established researchers and the general public alike. Rosie also gives a tremendous amount of her time to the scientific community, serving as a member of countless boards, and has been president of four international research associations: the American Arachnological Society, the International Society of Arachnology, the International Biogeography Society and the American Genetics Association. Being a president of one international society is a full-time job for most people, but not for Rosie. Rosie's unwavering passion for research is also what drives her unmatched work ethic. Rosie is the hardest-working person we've ever met. How she finds the time to write, teach, come up with ideas, handle massive amounts of administration and mentor students is beyond our grasp. Rosie's days start very early and often end late. Her true love is field work, something for which she finds far too little time in her busy schedule. But when she finally gets the chance to search Hawaii's forests for spiders, she is unstoppable, outpacing and outlasting everyone else in the group. When the rest of the team is ready to call it a night after hours of searching for spiders, Rosie is still just as energetic as when she started. ‘Just 5 more minutes’ is her most common catchphrase—there always seems to be just one more spider to find. Rosie has an incredible eye for spotting even the smallest and most elusive spider: winning a spider hunt against her is a futile endeavour. But even during field trips, her laptop is never far away, and she uses the precious time between spider hunts to catch up on all of her other work. Her students often joke that she would forget to eat if her husband George didn't remind her. George is also a professor at UC Berkeley, and he and Rosie co-lead a lab that's always packed with top-notch students and postdocs. In addition to fostering a warm, supportive lab group and advising dozens of PhD students, Rosie and George somehow carved out the time to raise two highly intelligent and conscientious sons who have now started their own successful careers. Somehow, Rosie's tireless work ethic and academic success have never stood in the way of kindness. She's living proof that you can be a world-famous scientist without being an egomaniac. Quoting one of her former postdocs, Rosie is ‘the sweetest person in the Bay Area’. We can only second this assessment. Rosie is warm, sincere and unfailingly polite, and gets along with even the most difficult personalities. Her office door is always open, and she always welcomes people in for impromptu meetings. It's no surprise that she received a US Presidential Award for Excellence in Science, Mathematics and Engineering Mentoring. Her passion for science is truly infectious, and her unshakable positivity has helped many of her lab members through difficult times. Rosie's attitude is that it's always worth reaching higher, pushing harder, staying in the field a little longer or applying for that grant even if the competition seems impossibly stiff. She believes in persevering even—and especially—when things aren't going well. Rosie is also legendary for her networking skills. She loves to meet and communicate about science and seems to know everyone in her research field and beyond. When a student is interested in something outside her main expertise, she always knows someone to refer them to. Long after people have left her lab, Rosie is still incredibly supportive and has helped many former PhD students and postdocs in their journey to secure faculty positions. Rosie's career in science arguably started early in her childhood. She was born and raised in rural Scotland, her family part of an old Scottish Highland clan. She grew up surrounded by farm animals, pets and wildlife, all of which fascinated her from a very young age. When she followed her older sisters to boarding school, she brought along her pet mice. She spent many hours designing crosses of the mice and observing the phenotypes of the offspring. Rosie's Latin teacher took an interest and introduced Rosie to her husband, who happened to be a famous quantitative geneticist: Professor Douglas Falconer of Edinburgh University. It was then that Rosie decided without any doubt that she wanted to study biology at this university. This she did, and graduated with Honors in 1980. Her subsequent research career was only briefly interrupted by a stint as a cook on a shrimping boat in Australia, a position she took to get close to the Great Barrier Reef and its biodiversity. Aside from cooking, part of her job was to help remove venomous sea snakes from the catch. Perhaps this experience solidified her desire to focus her research on spiders, most of which are harmless to humans! Being fascinated by spiders, she went on to start her PhD in the lab of Susan Riechert, a world leader in spider behavioural ecology, at the University of Tennessee in Knoxville. Determined to do her PhD in this field, Rosie did not apply to any other labs, but put all her eggs in one basket—luckily for her and everyone who had the pleasure to meet her. After a brief postdoc at the University of the South in Tennessee, Rosie departed for another postdoc at the University of Hawaii in Manoa. This moment was certainly decisive for her career, as it initiated her love for the Hawaiian Islands and their biodiversity, a love that persists today. Rosie's research career at UH Manoa had humble beginnings. She found small sources of money to sustain her research and basically lived in the Hawaiian rainforests, always driven by her insatiable hunger for knowledge. She stayed in Hawaii as an Assistant Professor and later an Associate Professor. Many of her pioneering studies on adaptive radiations and speciation on islands started around this time. Those years of focused field work gave Rosie unrivalled expertise in the native ecosystems of Hawaii. She knows Hawaii's forests like nobody else and can give you detailed advice on how to reach every field site on every island—many of these only accessible by helicopter or hours of hiking uphill. When most people think of Hawaii, they picture sparkling waters and black sand beaches, hot sun and fragrant plumeria trees. Rosie prefers to spend her time in Hawaii's native forests, which are about as far from this picture as you can get: cool, high-elevation, dominated by O'hia and Koa trees and primordial-looking tree ferns, and soaked with rain more often than not. Another running joke among her students is that she's never visited one of Hawaii's famous beaches—while this isn't entirely true, when she does have the opportunity to visit Hawaii, she certainly doesn't waste a moment away from the native forest! In 1996, after nearly 10 years on Hawaii, Rosie took an offer from UC Berkeley, where she has been working ever since. Leaving Hawaii, a place she cherishes so much and which laid the foundation for her research career, was one of the hardest decisions of her life. Not surprisingly, she and her husband George have kept their house in Honolulu and take every chance to visit the islands again. Difficult though the decision was, Rosie has unequivocally made the Bay Area her home, thriving in the fertile research environment of UC Berkeley. She is a Professor in the Department of Environmental Science, Policy and Management, an interdisciplinary department which promotes collaborations across topics in biological research. Rosie embraces this interdisciplinarity and has numerous running projects which integrate the research of scientists in ecology, evolution, data science, remote sensing and environmental policy. In addition to her position as Professor, Rosie is the William M. and Esther G. Schlinger Chair in Systematic Entomology and has served as Faculty Director of UC Berkeley's Essig Museum of Entomology. She teaches several courses, among which—naturally—is Spider Biology. As in her research, Rosie's palpable enthusiasm for teaching makes her courses favourites among the students. Photos of Rosemary Gillespie and a few of her study species. (A) Portrait of Rosie, (B) Rosie doing field work in Hawaii. (C, D) Spiny Leg Tetragnatha species of the (C) Large Brown (T. quasimodo) and (D) Green (T. kauaiensis) ecomorph. (E, F) Exemplary webs of orbweaving Hawaiian Tetragnatha species, showing differences in web structure. (E) T. stelarobusta, with densely woven web, (F) T. acuta, with widely spaced web mesh. (G, H) Ariamnes species of the (G) gold (A. kahili) and (H) white (A. corniger) ecomorph, showing how their coloration matches their resting substrate. Photos by George Roderick, Susan Kennedy and Joanne Clavel. S.K. and H.K. contributed equally to writing this article. The authors have nothing to report. The authors declare no conflicts of interest. Data sharing not applicable to this article as no datasets were generated or analysed during the current study.