The list of the Top 100 Authors reveals three notable features: First, absence of virtually any author who was scientifically active during the first 50 years of JCPA’s existence; second, exclusive presence of authors who were born at least five decades ago; and third, severe gender imbalance.

Investigators who were research active during the first 50 years of JCPA’s existence are (almost) entirely absent from the Top 100 authors list

The vast majority of authors on the Top 100 list published in JCPA primarily during the second 50 years of its existence, i.e., between 1974 and 2023. The only exceptions are Karl von Frisch, who published all his papers in the first half of JCPA’s 100 years of history; Hansjochem Autrum, whose last original research paper appeared in 1974; and Kurt Hamdorf, who published of his 31 articles in JCPA 18 between 1960 and 1973, and 13 between 1976 and 1992.

The phenomenon that 97% of the Top 100 Authors published exclusively, or primarily, during the second half of the 100 years of JCPA’s history can be explained by two peculiarities that distinguish the ‘early’ investigators from the ‘modern’ investigators. First, the number of papers of the early investigators was much lower than the number of papers produced by scientists of comparable peer recognition during the last 50 years. This discrepancy, in turn, has resulted in a lower number of citations. The deficit in the number of articles published in JCPA is not compensated by the much longer time that the early publications have been available for attracting citations because papers typically are cited most frequently during the first few years after their publication. Even Karl von Frisch, who was considered a highly prolific author of journal articles and books during his lifetime, published just 9 papers in JCPA. He made it onto the Top 100 Authors list based on the mean citation rate only.

A second feature that sets apart the early investigators from the modern ones is that they very rarely produced papers with more than two authors, and on most of their papers they appeared as single authors (for a detailed analysis of this phenomenon see Zupanc 2015). Since we scored authorship independently of the number of co-authors, our listing gives preference to individuals who have co-authored (as opposed to single-authored) articles. This bias is particularly extreme if the number of co-authors is large and the average contribution of a co-author to these papers is small, compared to the investments that a single author must make to conduct the entire research and write the paper.

It takes (almost) a lifetime to make it on the Top 100 Authors list

Besides the absence of early investigators (with the exception of Karl von Frisch) on our list, a notable feature characteristic of each of the Top 100 Authors is that they were born at least five decades ago. Of those authors who are still alive, and we know the year of birth, Nathan Hart, born in 1973, is the youngest. In most cases, this reflects the significant amount of time it takes to produce enough papers and/or attract enough citations to be included in the Top 100 Authors list. Only four of the authors who were selected based on the total number of citations have published 10 or less papers in JCPA. They include Colin Stephenson Pittendrigh and Serge Daan who published 7 and 10 papers, respectively. Nevertheless, these two authors top the mean citation rate list with 531 and 371, respectively. Five of their papers, each jointly authored, appeared in a single issue of JCPA, in October1976 (Pittendrigh and Daan 1976a, b, c; Daan and Pittendrigh 1976a, b). Reflecting the enormous impact that these five articles have had, this issue is frequently referred to as the ‘Bible of Chronobiology.’

Women scientists are disturbingly underrepresented on the Top 100 Authors list

Among the Top 100 Authors, there are only 7 women (Almut Kelber, Hanna Mustaparta, Gerbera Nalbach, Andrea Megela Simmons, Marianne Vater, Dora Fix Ventura, Roswitha Wiltschko). This finding comes as no surprise, given the severe underrepresentation of women among biology faculty during the last 100 years. We hypothesize that this disturbingly low number of women on our list primarily reflects the lack of adequate opportunities that women have traditionally encountered for a long time as they tried to establish their own laboratories and research programs. Without this foundation, they were deprived of the essential instrument for making it to the Top 100 Author list—the production of a large number of papers that attract a large number of citations. Two women scientists who had the potential to become leading zoologists of their times were Ruth Beutler and Ingeborg Beling. Both are portrayed in this Special Issue (Zupanc 2023; Beer et al. 2024). Beutler was never considered for appointment to a faculty position that would have enabled her to establish her own laboratory. For many years, she was employed by Karl von Frisch only as a technician at his institute—after she had received her PhD and even the Habilitation. Beling made a breakthrough discovery—time memory in honeybees—during her thesis research and established an excellent publication record after she received her PhD under von Frisch’s mentorship. However, she left science when she married, presumably due to political and/or societal pressure that even forced highly qualified women (like her) into the role of housewives.

In our metanalysis, we also considered the possibility that even women who succeeded in establishing their own publication records were still disadvantaged by gender bias in citation practice. This issue was recently highlighted by Dworkin et al. (2020) who analyzed the papers of five neuroscience journals (Brain, Journal of Neuroscience, Nature Neuroscience, NeuroImage, and Neuron). They found that reference lists tended to include more papers with men as first and last authors than was expected if gender were unrelated to referencing. Prompted by this finding, we first compared the mean citation rates of the articles of the five women who qualified for inclusion in the Top 100 Authors list by number of publications in JCPA (i.e., independent of any citation record) with the mean citation rates of all 54 authors in this criterion list. The median values of these two groups were almost identical (41.8 for all 54 authors vs. 40.9 for the five women). The publications of two of these five women exhibited mean citation rates above the overall median, whereas the mean citation rates of the publication of the other three women were below the overall median. Then, we took a closer look at the mean citation rates of the papers in JCPA. Two of the seven women had been selected based on this criterion. The value of this performance indicator of one woman was higher (102.3) than the median of the mean citation rate of all 54 authors in this selection category (87.8), while the corresponding value of the other woman author was lower (71.8). Thus, while we would like to stress the limitation of our analysis due to the small sample size, we have not found an indication of pervasive gender imbalance in citation practice toward papers published in JCPA by women, compared to men.

We believe that the latter finding, together with the significant increase in the number of women principal investigators in neuroethology and related disciplines over the last few decades, gives reason for hope. If a list of top authors would be compiled, let’s say at the 125th anniversary of JCPA, the gender distribution among these individuals is likely to be more balanced than it is today.

The Top 100 Authors: their academic careers and major scientific achievements

In the following, we list the Top 100 Authors in alphabetical order. For each of them, we present biosketches that highlight milestones of their academic careers and scientific achievements. The main sources of the biographical information were autobiographies and obituaries, the authors themselves and/or collaborators, as well as public information from the Internet. In some instances, the amount of information available was rather limited, which has unfortunately resulted in imbalances in length of the biosketches. These differences should not be interpreted as differences in the significance of the contributions made by authors to scientific knowledge.

To indicate links between different authors, we have marked names of authors mentioned in biosketches other than their own with an asterisk.

Edmund A. Arbas (1950–95) earned his PhD from the University of Oregon in 1980 studying the muscular and neural correlates of flight loss in a grasshopper, supervised by Graham Hoyle. His interest in pattern-generating networks led him to pursue postdoctoral training studying the neural mechanisms of heartbeat and its modulation in the leech with Ronald Calabrese at Harvard University. Following a second postdoctoral position with Barry Ache at the University of Florida, where he performed intracellular recordings from olfactory interneurons in the crayfish, he became assistant (1986) and later associate professor at the Arizona Research Laboratories, Division of Neurobiology at the University of Arizona. Here he continued research on muscle degeneration in grasshoppers but also became interested in insect olfactory coding. Five of his 10 papers in JCPA contributed significantly to research on moth olfactory behavior and central nervous coding of pheromone signals in the moth brain. In 1995, while on a sailing trip with his family in Mexico, he died in a tragic accident.

Kentaro Arikawa (1957-) was born in Tokyo. He is professor and executive director of the Research Center for Integrative Evolutionary Science at Sokendai, Japan. Arikawa studied natural science at Jiyu Gakuen College and received his PhD in behavioral biology (1986) from Sophia University, analyzing the unique photoreceptive system of butterfly genitalia. He continued to work on vision in butterflies as research assistant and later full professor at Yokohama City University, interrupted by research positions at Indiana University and the Australian National University in Canberra. In 2006, he moved to his current position at Sokendai. Arikawa has received several prestigious awards, including the National Medal with Purple Ribbon from the Emperor of Japan in 2022. His continuing interest (as he puts it himself) is “how do animals see the world”. His studies on color vision in insects, mostly in Papilio butterflies, are comprehensive and include anatomical, ultrastructural, physiological and behavioral techniques. He has served on the editorial board of JCPA since 2009 and has contributed 26 highly cited papers on the visual behavior and photoreceptor physiology of butterflies.

Harold L. Atwood (1937-) was born in Montreal. His academic training was in biology and neurophysiology, and he studied at the University of Toronto (BA, 1959), the University of California Berkeley (MSc, 1960), and the University of Glasgow (PhD, 1963; DSc, 1979), where he worked with C.M. Yonge and Graham Hoyle. He conducted postdoctoral research with Graham Hoyle at the University of Oregon and with C.A.G. Wiersma at the California Institute of Technology. Atwood joined the faculty of the University of Toronto in 1965, and remained there until his retirement in 2002. He directed the Medical Research Council of Canada Research Group in Nerve Cells and Synapses. His many awards include a Guggenheim Fellowship (1972), Fellow of the American Association for the Advancement of Science (1981), Fellow of the Royal Society of Canada (1982), Distinguished Scientist of the Medical Research Council of Canada (1997), and Fry Medal of the Canadian Society of Zoologists (1997). Atwood’s 13 publications in JCPA concern the physiology of muscular contraction, motor control, synaptic transmission, and synaptic modification (long-term facilitation and low-frequency depression) in the nervous and neuromuscular systems of crustaceans and fruit flies.

Hansjochem Autrum (1907–2003) was a giant in the field of sensory physiology for most of the twentieth century. He was the editor-in-chief of JCPA from 1960–96 (he was also editor-in-chief of Naturwissenschaften in parallel). He studied mathematics and physics (with a minor in biology) at the Humboldt University in Berlin, and received a PhD under the supervision of Richard Hesse in 1931. After the Second World War, Autrum became adjunct professor at the University of Göttingen (1948), full professor at the University of Würzburg (1952), and Head of the Zoological Institute of the Ludwig Maximilian University of Munich (LMU Munich) (1958). He was also highly active in science politics and was instrumental in the foundation of three major German universities: University of Regensburg, University of Bayreuth, and University of Konstanz. He was elected as a member of the German National Academy of Science (Leopoldina) in 1957 and as a member of the Bavarian Academy of Sciences in 1958. He received the Feldberg Foundation Prize in 1966, was admitted to the order Pour le Mérit for Sciences and the Arts in 1977, and received the Bavarian Maximillian Order for Science and Art in 1984. Autrum made groundbreaking foundational studies on the sensory systems of animals, including the discovery of the extraordinarily low vibrational sensitivity thresholds of bush crickets and cockroaches (with threshold amplitudes in the order of atomic diameters!). He also made seminal studies of the physiological properties of insect eyes, including their temporal and spectral sensitivities, and was a pioneer of intracellular recordings in photoreceptors.

Friedrich G. Barth (1940-) was born in Munich. He attended LMU Munich for his undergraduate studies in zoology, botany, physics, chemistry, and human physiology from 1959–62. Subsequently, he went to the University of California Los Angeles, to join the laboratory of Theodore H. Bullock* as a Fulbright Scholar. After returning to LMU Munich, he obtained his PhD under the mentorship of Hansjochem Autrum* in 1967, followed by the Habilitation in 1971. Between 1974 and 1987, he served on the faculty of Goethe University Frankfurt, and from 1987–2008 he was professor and chair of the Department of Neurobiology at the University of Vienna. Since 2008, he has been emeritus professor. During his scientific career, Barth has addressed important biological questions, particularly in the context of social communication, by combining sensory physiology with physics and engineering; and by complementing laboratory experiments with field observations in search of matches between properties of sensors and behavior and ecology. One of his major research interests has been vibratory communication in spiders and the functional biomechanics of cuticular strain receptors (a class of sensors that includes the spider vibration receptor). Since the early 2000s, he has increasingly turned his attention to the analysis of the signals and cues used by stingless bees for recruitment of nestmates to food sources—research that was largely based on fieldwork in Brazil. Barth has been closely affiliated with JCPA as both author and editor. His first paper, a physiological characterization of a phasic-tonic proprioceptor in the telson of the crayfish, appeared 60 years ago (Barth 1964). His last papers, including the most frequently accessed article of the last 100 years (Dyer et al. 2021), were published in 2021. In total, Barth has authored 64 publications in JCPA, which distinguishes him as the most prolific JCPA author of all times. Perhaps even more impactful was his service as editor-in-chief, a responsibility he assumed in 1996 when Hansjochem Autrum* retired from this position. Barth carried out this task with great dedication over the following 25 years, during which he left his editorial mark on numerous articles published in JCPA.

Joseph A. Bastian (1944-) was born in Mare Island, California. After completing his undergraduate education at Elmhurst College (1966), he went to the University of Notre Dame, where he studied, both as a graduate student and as a postdoctoral fellow, bee communication and flight muscle physiology in the laboratory of Harald Esch. Each of the four papers that resulted from this work was published in JCPA. In 1969, he joined the lab of Shigehiru Nakajima at Purdue University to continue postdoctoral training in muscle physiology but, at the same time, he changed organisms from invertebrates to vertebrates. During his third postdoctoral stint, from 1972–74, in the laboratory of Theodore H. Bullock* at the University of California San Diego, Bastian began to address the question that became central to the research program he subsequently established as a faculty member at the University of Oklahoma: how does the central nervous system process electrosensory information in weakly electric fish? In recognition of his accomplishments, he received several distinctions, including the Jacob Javits Neuroscience Investigator Award. He was also named the George Lynn Cross Research Professor by the University of Oklahoma. Currently, Bastian is emeritus professor. The impact of the papers that he published in JCPA is not only evident from their large number (21), but also the many citations they have attracted—over 1400 in total and nearly 70 on average.

Horst Bleckmann (1948-) was born in Rietberg, Germany. After successful completion of an apprenticeship as a machinist, he earned the Abitur (the German high school diploma) through second-chance education. He then studied biology and chemistry at the University of Giessen, where he also received his PhD in 1979. Following his Habilitation in 1986, Bleckmann worked with Theodore H. Bullock* as a Heisenberg Fellow at the Scripps Institution of Oceanography of the University of California San Diego, and at the University of Bielefeld. In 1994, he was appointed to a full professorship at the University of Bonn, where he served on the faculty until 2017. His research covered a wide range of topics within neurophysiology and sensory physiology, neuroethology, and bionics. However, he is best known for his studies exploring how sensory information perceived through the lateral line system of cartilaginous and bony fishes is processed by the central nervous system. Part of this research led to the development of bionic sensors. Bleckmann has been a prolific author, with 42 highly cited articles published in JCPA. He has also contributed an autobiographical essay to this Special Issue.

Reinhard Blickhan (1951-) was born in Eppertshausen, Germany. He studied physics at the University of Giessen and the Technical University Darmstadt and received his Diplom (master’s) degree in 1976. Over the following 40 years, he applied his training in physics to study phenomena in biomechanics. The foundation for this interdisciplinary career was laid during his PhD thesis research on ‘Strain in the exoskeleton of spiders’ in the laboratory of Friedrich G. Barth* at Goethe University Frankfurt, for which he was awarded a Dr. rer. nat. degree in 1983. Following postdoctoral training at Harvard University and the Habilitation at the University of Saarland, he was appointed professor of biomechanics at the University of Jena in 1993, where he served on the faculty until his retirement in 2016. By combining experimental studies with numerical simulation, a major focus of his research was on the biomechanics of terrestrial and aquatic locomotion. The impact of Blickhan’s work is evident, among other indicators, by the nearly 125 citations that each of his 6 papers published in JCPA have attracted on average.

James K. Bowmaker (1946-) is emeritus professor of ophthalmology at University College London (UCL). He was educated at Queen Mary University of London, receiving a bachelor’s degree (1967) and a PhD (1970) in zoology for his work on visual transduction. He then pursued postdoctoral work with Frederick Crescitelli at the University of California Los Angeles (1970–72) and with Herbert Dartnall at the Medical Research Council Vision Unit at the University of Sussex (1972). It was with Dartnall that he first began using microspectrophotometry to measure the absorption characteristics of visual pigments in humans and monkeys. Bowmaker took a faculty position first as lecturer (1977) and then as reader (1987) at Queen Mary College. He moved to the Institute of Ophthalmology at UCL in 1989, becoming professor of vision research in 1994. He was awarded the Rank Prize for optoelectronics (1988) and is an honorary member of the Colour Group (Great Britain). Bowmaker’s research interests focus on the evolution and functions of visual pigments and color vision in vertebrates. In eight papers in JCPA, he presented new data on photoreceptors and visual pigments in several species of birds, fishes, and chameleons. He found that birds and freshwater fish have four visual pigments, including an ultraviolet-sensitive pigment, thereby possessing tetrachromatic color vision.

Heinz Breer (1946-) was born in Wieste, Germany. He studied biology and chemistry at the University of Münster from 1968–72 and received his PhD from the University of Hohenheim in 1974. After postdoctoral training at the Max Planck Institute for Biophysical Chemistry in Göttingen, he worked for 10 years as a scientific assistant at the University of Osnabrück, where he received the Habilitation in zoology in 1982. In 1987, he was appointed to a professorship in physiology at the University of Hohenheim. During the following three decades of his tenure, Breer also served as vice president of the University and dean of the College of Science. After his retirement in 2018, he was re-appointed to the University as its first senior professor. Breer’s research activities are mainly in neurochemistry, with an emphasis on olfaction and gustation. He published approximately 300 papers, of which six appeared in JCPA. On average, each of the latter publications has been cited nearly 90 times, underscoring the impact of his research.

Theodore H. Bullock (1915–2005; for obituaries see Zupanc 2006; Zupanc and Zupanc 2008) was born to American Presbyterian missionaries in Nanking, China. His immersion in the Chinese culture over the first 13 years of his life laid the foundation for his lifelong cosmopolitan outlook. He received his undergraduate degree (1936) and then his PhD in zoology from the University of California Berkeley (1940), working with S.F. Light. He then spent four years at Yale University, with summers at the Marine Biology Laboratory at Woods Hole. There, the ample opportunity to work on a large variety of organisms had a major impact on the development of his interest in comparative physiology. Later, he would argue that examination of the different mechanisms used by various organisms is as important as the search for commonalities in understanding how the brain works. As a consequence, during his tenure as a faculty member at the University of California Los Angeles (1946–66), and the University of California San Diego (1966–2005), Bullock studied an enormous variety of taxa, including cnidarians, crustaceans, fish, amphibians, and reptiles. He was a member of the US National Academy of Sciences (elected 1963), the American Academy of Arts and Sciences (1961), and the American Philosophical Society (1970). He served as the first president of the International Society for Neuroethology (1984), the third president of the Society for Neuroscience (1973–74), president of the American Society of Zoologists (1965) and of the American Association of University Professors (1955–56). He was awarded the Ralph W. Gerard Prize from the Society for Neuroscience (1984) and the Karl Spencer Lashley Award from the American Philosophical Society (1968). Bullock’s research interests were diverse and included, among others, the study of physiological processes at chemical and electrical synapses, the anatomy and physiology of sense organs, the analysis of electrical brain activity associated with cognitive events, and the mathematical modelling of neurophysiological activity. His many ‘firsts’ include the discovery of two new senses in animals—the facial pits of pit vipers that act as thermal sensors, and electroreceptors in the skin of certain fish. Equally important, he inspired numerous students and co-workers all over the world to identify new research directions and to establish their own field of study—an influence that can be felt even today. His 21 articles published in JCPA have attracted nearly 1100 citations.

Jeffrey M. Camhi (1941-), born in New York, is professor emeritus of cell and developmental biology and founding director of ‘Nature Park and Galleries,’ an open-campus museum, at the Hebrew University of Jerusalem. Camhi earned his bachelor’s degree at Tufts University and his PhD (1967) at Harvard University under the direction of Ian Cooke. His dissertation examined the operation of wind receptors in the locust. He joined the faculty in the Department of Neurobiology and Behavior at Cornell University in 1967, where he trained Roy Ritzmann*. In 1982, Camhi accepted a faculty position in the Department of Cell and Animal Biology at Hebrew University Jerusalem, where he spent the rest of his academic career. His 1984 book, Neuroethology: Nerve Cells and the Natural Behavior of Animals (Sinauer) inspired many students to enter the field. Currently, he is actively involved in developing strategies to improve public outreach and education in science and nature. Camhi’s 35 papers in JCPA contribute a neuroethological analysis of the escape system of the cockroach. He determined the threshold wind velocity needed to evoke the escape response, how these responses are coded by in the nervous system, and developed a model of the escape system based on synaptic responses of different populations of interneurons.

Robert R. Capranica (1931–2012) was born in Southern California and was a resident of Tucson, Arizona at the time of his death (see obituary by Adler et al. 2013). After service in the US Navy (1951–54), he received his BA in electrical engineering from the University of California Berkeley in 1958. Capranica then moved to New York University, where he received his MS, and then to the Massachusetts Institute of Technology (MIT) from which he received his ScD in electrical engineering in 1965. At MIT, he studied with Moise Goldstein, Lawrence Frishkopf, and Jerome Lettvin. It was Lettvin’s pioneering work on “what the frog’s eye tells the frog’s brain” that inspired Capranica to examine “what the frog’s ear tells the frog’s brain.” Capranica’s dissertation, published as a monograph titled The Evoked Vocal Response of the Bullfrog (MIT Press, 1965), remains a model of how to incorporate engineering and biology to answer questions about evolution and adaptation to the environment. His first position after MIT was at the Bell Telephone Laboratories in Murray Hill, New Jersey (1958–69). He was recruited to Cornell University in 1969, with appointments in the Department of Neurobiology and Behavior and the Department of Electrical Engineering. At Cornell he built a large laboratory dedicated to the integrative study of the auditory system of anuran amphibians. Six of his trainees and collaborators are included among the Top 100 Authors listed here (Günther Ehret*, Albert Feng*, Howard Carl Gerhardt*, Peter Narins*, Gary Rose*, Andrea Megela Simmons*). Capranica served as an associate editor of JCPA from 1974–86, and is one of the founding members of the International Society for Neuroethology. He was an elected Fellow of the Acoustical Society of America (1974) and of the International Society for Neuroethology (2012). He and his spouse Patricia endowed the Capranica Fund at the International Society for Neuroethology to celebrate the achievements of young neuroethologists. Capranica retired from Cornell in 2012 and moved to Arizona. His 20 papers in JCPA integrated field studies and laboratory electrophysiological methods to decipher how species-specific advertisement calls are produced, recognized, and encoded in the brain. These papers quantify the frequency tuning of the frog’s inner ear and how it relates to the spectral content of the advertisement call; sex differences in the tuning of the inner ear; acoustic sensitivity of the frog’s midbrain and thalamus; mechanisms by which small frogs can localize sound sources; and the use of spectroscopy to measure the mechanics of the middle ear.

Lars Chittka (1963-, born in Bad Homburg, Germany) is professor of sensory and behavioral ecology at Queen Mary University of London. He was educated at the University of Göttingen and the Free University of Berlin, where he received his PhD under the mentorship of Randolf Menzel*. He is a member of the German National Academy of Science (Leopoldina), and Fellow of the Linnean Society, the Royal Society of Biology, and the Royal Entomological Society. In 2006, he received the latter’s Lesley Goodman Award. Chittka has made seminal contributions to our understanding of insect color vision and the interactions of insects with flowers, and his work on the cognitive abilities of bumblebees has changed the way we understand the evolution of animal cognition and its neural underpinnings. He is well known for his work exploring the behavior, cognition, and ecology of bees, a topic he summarized in his 2022 book The Mind of a Bee (Princeton University Press). He has collaborated in several musical and artistic compositions based on bee biology. Chittka’s 11 papers published in JCPA—nearly all of which deal with color vision in bees—have been highly cited. A good example is his 1992 analysis (with Randolf Menzel*) of 180 floral spectral reflection spectra showing that flower colors are well matched to the color vision of bees (Chittka and Menzel 1992, with 304 citations as of November 2023).

Thomas A. Christensen (1956-) was born in Queens, New York. He earned his BSc in biology from the State University of New York at Stony Brook and his PhD from the same institution in 1983 for research supervised by Albert Carlson on the neural control of luminescence in the firefly. For postdoctoral training, he joined the group of John Hildebrand* at Columbia University, and moved with him to the University of Arizona in late 1985 to become senior research scientist at the Arizona Research Laboratories, Division of Neurobiology. There, he performed groundbreaking work in analyzing the mechanisms of olfactory signal processing in the brain of the sphinx moths and, in collaboration with Hanna Mustaparta*, characterized the olfactory system of heliothine moths. Motivated by an increasing interest in human studies, in 2006 Christensen moved within the University of Arizona to the Department of Speech, Language and Hearing Sciences to perform MRI studies on attention and language representation in the human brain. In 2012, he left the University of Arizona to take on a teaching position at Pima Community College. In 11 highly cited articles in JCPA, he contributed significantly to our understanding of how pheromone signals are processed in the brain of sphinx moths and heliothine moths.

François Clarac is emeritus research director at the French National Center for Scientific Research (CNRS) Aix-Marseille. He continues to teach at Aix-Marseille and at Montpellier. He is a Member of the Academy of Europe (elected 1996) and the Académie de Marseille (elected 2006). He served as Chancellor of the Académie de Marseille in 2011, and as Director in 2012 and 2014. Clarac’s research focuses around cellular mechanisms of locomotion, neural bases of rhythmic behavior, and developmental plasticity of the spinal cord. He has collaborated with Douglas M. Neil* on comparative studies of the swimmeret system in crustaceans. Currently, Clarac continues to write and speak on the history of neuroscience and on the importance of neuroscience research. Together with Jean-Peirre Ternaux, he has authored two books, Encyclopédie historique des neurosciences: Du neurone à l'émergence de la pensée (Historical Encyclopedia of Neuroscience: From Neuron to the Emergence of Thought; de boeck, 2008) and Le Bestiaire cérébral (The Cerebral Bestiary, CNRS Editions, 2012).

Thomas S. Collett (born 1939 in London) is emeritus professor of neurobiology at the University of Sussex. He studied psychology and zoology at University College London, and received his PhD with David Blest working on visual behavior of moths. Inspired by Hubel and Wiesel’s work on the visual cortex, they pioneered physiological recordings from motion-sensitive interneurons in moths. In 1965, Collett was appointed assistant lecturer at the University of Sussex and later progressed to the rank of full professor. He is a Fellow of the Grass Foundation (1965). Collett has contributed significantly to the study of insect vision, spatial orientation, and navigation. His interests focus on behavioral studies of navigation, landmark learning, and spatial memory in flies, ants, and bees. His meticulous observations on landmark learning in bees and ants, as well as his studies on visual control of flight behavior in hoverflies, received record numbers of citations. Out of well over 170 papers, he published 32 highly cited articles on these topics in JCPA.

Thomas Cronin (1945-) is renowned for his decades of research on the visual systems of crustaceans, and particularly on the remarkable polarization and color vision of mantis shrimps. Educated at Dickinson College (BSc, 1967) and Duke University (MA, 1969; PhD, 1979), he studied crustacean visual pigments in the lab of Timothy Goldsmith at Yale University before joining the University of Maryland Baltimore in 1983, where he is now professor of biological sciences. Cronin’s chief interest is understanding how the visual systems of animals are matched to their habitats and lifestyles, a field known as ‘visual ecology.’ Together with Sönke Johnsen, Justin Marshall*, and Eric Warrant*, Cronin authored a book on this topic—Visual Ecology (Princeton University Press, 2014)—which is now the most important work in the field. For his many contributions to visual ecology, Cronin was elected as Fellow of the International Society of Neuroethology in 2014. Cronin’s many well-cited papers in JCPA deal with color and polarization vision in mantis shrimps, mysids, crayfish and insects, with notable contributions to our understanding of how visual pigments are spectrally tuned for vision in specific light environments (e.g., at different depths in the ocean) and for different tasks (e.g., for detecting specific colors of bioluminescence).

Serge Daan (1940–2018; see obituary by Trillmich et al. 2018) was an inspiring scientist who contributed seminal work to the fields of chronobiology, sleep research, psychiatry, physiology, ecology, and behavioral biology. Daan studied biology at the University of Amsterdam and received his PhD on hibernation of bats and mice in 1973. In 1971, while still finishing his PhD thesis, he became a postdoctoral researcher with Jürgen Aschoff at the Max Planck Institute for Behavioral Physiology in Erling-Andechs. The time with Aschoff founded his lifelong interest in the role of circadian clocks in seasonal timing and their significance in an ecological context. Through Aschoff, Daan met Colin Stephenson Pittendrigh* with whom he spent his second postdoctoral position at Stanford University. During his stay at Stanford, he wrote a series of five papers together with Pittendrigh (‘A functional analysis of circadian pacemakers in nocturnal rodents,’ Parts I-V), which appeared as a single issue of JCPA in 1976. This series of papers belongs to the highest cited research papers in JCPA and has become the ‘Bible of Chronobiology’ for hundreds of students and scientists. In 1975, Daan moved to the University of Groningen where he was appointed professor of ethology in 1996. In 2003, he was promoted to the prestigious Niko Tinbergen Chair in Behavioral Biology, which he held until his retirement in 2011. He was awarded several prizes and awards, including the International Prize for Biology (2006), conferred by the Emperor of Japan. He was appointed Knight in the Order of the Dutch Lion (2005) and was elected Foreign Fellow of the Royal Society of Canada (2000). Daan (co-) supervised more than 40 PhD students. Most of them pursued successful careers in science. His work became more eco-physiologically oriented by focusing on kestrel-vole interactions in relation to energy expenditure. ‘Time and Energy’ was a central theme in his Chronobiology group. EEG recordings during sleep made together with Alex Borbély and Domien Beersma led to the development of the ‘Two Process Model’ of human sleep regulation, a model which still inspires many sleep researchers all over the world. He stayed active after retirement. His last publication, the biography of Jürgen Aschoff—Die Innere Uhr des Menschen: Jürgen Aschoff (1913–1998), Wissenschaftler in einem bewegten Jahrhundert (The Biological Clock of Humans: Jürgen Aschoff (1913–1998), Scientist in a Turbulent Century; Reichert, 2017), appeared two months before his death. He has published 10 highly-cited papers in JCPA.

William Jackson Davis is founder and executive director of the Environmental Studies Institute. He received his BA in zoology (1964) at the University of California Berkeley and his PhD in biology (1968) under the direction of Graham Hoyle at the University of Oregon. Davis pursued postdoctoral research with Melvin Cohen (University of Oregon, 1967–68) and with Donald Kennedy (Stanford University, 1968–70), where he investigated motor control in lobsters. He joined the Department of Biology at the University of California Santa Cruz in 1969, and remained there as professor of ecology and evolution and of environmental sciences until 2004. In 1981, Davis founded the non-profit Environmental Studies Institute. The mission of this institute is to research and consult on matters of importance to public policy, such as radioactive waste, nuclear proliferation, climate change, and biodiversity. Davis has published extensively in the areas of biological sciences, environmental sciences, health and fitness, and public policy. His 17 papers in JCPA analyze the hormonal and neural control of motor behavior in invertebrates, with an emphasis on the physiology of command neurons in the buccal ganglion of sea slugs; the role of internal states in controlling slug feeding behavior; and the neural and behavioral control of walking and swimmeret motion in lobsters.

John Manuel De Souza (1930–2016) was professor at the Institute of Psychology at the University of São Paolo. He earned undergraduate degrees in civil and electrical engineering at Mackenzie Presbyterian University in Sao Pãolo (1955). After a career in business, in 1983 he returned to academia, enrolling in the University of São Paolo. He received his master's (1986) and PhD (1993) degrees in experimental psychology, working with Dora Fix Ventura* on the neural coding of visual cues in the retina and first visual ganglion of Hymenoptera. He continued to collaborate with Ventura throughout his career on projects related to the spectral sensitivity and morphology of insect compound eyes and the electrophysiology of the visual system. In 1984 and 1985, de Souza worked with Randolf Menzel* at the Free University of Berlin to characterize and compare color vision sensitivity of photoreceptors in closely related hymenopterans. His six publications in JCPA describe the use of intracellular recordings to elucidate the operation of photoreceptor cells and other retinal cells in multiple hymenopteran species; how the color vision system of these animals has evolved to adapt to different ecologies and behavioral demands; and to characterize the ultraviolet sensitivity of the goldfish retina.

Günter Ehret (born 1949, Kaiserslautern, Germany) is professor emeritus for neurobiology at the University of Ulm, Germany. Ehret studied chemistry and biology at the Technical University of Darmstadt and received his doctorate (Dr. rer. nat.) in 1975 for studies on the auditory system of mice, supervised by Hubert Markl. He moved as research assistant with Markl to the University of Konstanz, where he received his Habilitation (1981) followed by a Heisenberg Stipend (1982–85) from the German Science Foundation. As a visiting professor at Cornell University, he conducted behavioral and electrophysiological studies on hearing in frogs in conjunction with Robert R. Capranica*, and at the University of California San Francisco, he examined neural coding of complex sounds in the inferior colliculus of cats in collaboration with Michael Merzenich. In 1993, Ehret received the Merckle Research Award for Natural Science. In 1988, he became professor for neurobiology at the University of Ulm where he stayed until retirement in 2014. Ehret’s scientific interests focus on the auditory system and acoustic communication in mice, but he also contributed to studies in insects and frogs. In more recent years, his interest shifted to evolutionary and emotional aspects of auditory communication and the neural basis of awareness and consciousness. Out of well over 100 publications in peer-reviewed journals, numerous book chapters, and two books, he published 13 papers in JCPA and, together with Henning Scheich*, he edited an extremely well-received Special Issue on Auditory Cortex (Volume 181, Issue 6, 1997).

Joachim Erber (1946-) was born in Wiesbaden, Germany. He studied electrical engineering at the Technical University of Darmstadt. In his Diplom (master’s) thesis he developed a model of photoreceptor function. He subsequently shifted further into the field of zoology and completed his dissertation, supervised by Randolf Menzel* and Hubert Markl, on learning dynamics in the honeybee. As a postdoctoral researcher in Menzel’s group, Erber performed electrophysiological studies on interneurons in the brain of bees and shore crabs, and spent a year at the Australian National University studying the visual interneurons of crayfish. In 1976, together with Menzel, he moved as assistant professor to the Free University of Berlin and continued behavioral and electrophysiological studies on olfactory learning in honeybees and visual signal processing in crabs. Following his Habilitation in 1978 and a research stay at the University of Sussex, Erber became professor of animal physiology at the Technical University of Berlin in 1982. There, he developed various learning paradigms for honeybees and studied the underlying neural mechanisms. In his later years, a focus of his research became the involvement of biogenic amines, and the identification of amine receptors, in the honeybee brain. In collaboration with Robert Page at Arizona State University, he analyzed the physiological basis of differences in honeybee foraging behavior. Erber retired in 2011. He published his data on learning assays, the effect of sensory thresholds on learning, and the role of biogenic amines on honeybee learning in 22 articles in JCPA.

Jörg-Peter Ewert (1938-) is one of the pioneers of neuroethology who unraveled the neurophysiological bases of visually controlled behavior in the toad. Ewert was born in Danzig and studied biology, chemistry and geography at the University of Göttingen. After graduation (1965), he worked as a scientific assistant at the Zoological Institute of the Technical University of Darmstadt until 1969, first under Wolfgang Luther and then under Hubert Markl. During a research visit at the Free University of Berlin, Ewert learned electrophysiological recordings and began to record from neurons in the visual system of the common toad. He obtained his Habilitation from the Technical University of Darmstadt in 1969. From 1970–71, he worked with David J. Ingle at the Harvard Medical School, and from 1971–72 as a university professor at the Zoological Institute of the Technical University of Darmstadt. In 1973, Ewert became the chair of zoology/physiology at the Faculty of Natural Sciences at the University of Kassel, where he formed a neuroethology research team and where he remained until his retirement in 2006. In 1980, he published his book Neuroethology: An Introduction to the Neurophysiological Fundamentals of Behavior (Springer, 1980), which inspired many neuroethologists. He is an elected Fellow of the American Association for the Advancement of Science (1983). Ewert’s 41 papers published in JCPA describe, analyze, and model the release of visual behaviors in prey-catching toads.

Albert S. Feng (1944–2021; for an obituary see Narins and Feng 2023) made fundamental discoveries in neuroethology and comparative physiology, probing acoustic communication in frogs, electroreception in electric fishes, and echolocation in bats. Feng was born in Bandung, Indonesia, and moved to the US to study electrical engineering at the University of Miami. He earned his BA in 1968 and his master’s in 1970. He received his PhD in electrical engineering (1975) at Cornell University under the mentorship of Robert R. Capranica*. Feng pursued postdoctoral studies on electroreception (1976) with Theodore H. Bullock* at University of California San Diego and on echolocation (1977) with James A. Simmons at Washington University. He joined the faculty at the University of Illinois in 1977, remaining there until his retirement in 2010. At Illinois, he served as department head of molecular and integrative physiology and as director of the neuroscience program at the Beckman Institute. He played an essential role in building and expanding Beckman’s neuroscience program, and was highly respected as a teacher and educator. He traveled extensively to conduct field work on vocalizing frogs and echolocating bats. Feng was an elected Fellow of the Acoustical Society of America (1997), the American Association for the Advancement of Science (1993), and the Alexander von Humboldt Foundation (1988). His 26 papers in JCPA analyze perception and localization of advertisement calls by frogs, neural coding of these advertisement calls, and neural mechanisms of target ranging in echolocating bats. This work inspired his development of a novel hearing aid for canceling out background noise. Along with Peter M. Narins*, Feng was a member of the team that discovered the ability of some specialized frog species to hear ultrasound. A Special Issue devoted to him and his work (Neuroethology of Auditory Systems: Contributions in Memory of Albert S. Feng) was published in JCPA (Volume 209, Issue 1, 2023).

Russell G. Foster (1959-) is the director of the Nuffield Laboratory of Ophthalmology, the Head of the Sleep and Circadian Neuroscience Institute, and a Nicholas Kurti Senior Fellow at Brasenose College at the University of Oxford. He studied at the University of Bristol, receiving his PhD in 1984 for a thesis on how extraretinal photoreceptors mediate photoperiodic induction in Japanese quail. Furthermore, he showed that the pineal eye of Xenopus can directly excite behavior, work that was published in JCPA in 1982. From 1988–95 he conducted postdoctoral work at the University of Virginia with Michael Menaker*. During this time, Foster, Martin Ralph, and Menaker carried out their impactful transplantation experiments that showed that the mammalian suprachiasmatic nucleus is sufficient and necessary for mammalian circadian rhythms. In addition, Foster found that mice with degenerated retinas can still synchronize their circadian rhythms to light–dark cycles, providing evidence that rods and cones are not necessary for circadian entrainment. This seminal paper appeared in JCPA in 1991 and was highly cited. Later he showed that melanopsin in the retinal ganglion cells works as a circadian photoreceptor. In 1995, Foster returned to the UK and started his own laboratory at Imperial College in London where he became chair of molecular neuroscience within the Faculty of Medicine. Later, he transferred his laboratory to the University of Oxford to engage in translational research, investigating the importance of circadian clocks and sleep for human health. He has been awarded many prizes, and his contribution to science has been recognized by his election as Fellow of the Royal Society and as Fellow of the Academy of Medical Sciences, culminating in the 2015 New Year’s honors with the award of Commander of the Order of the British Empire. Foster has published more than 100 research articles, four popular science books and writes newspaper articles. He regularly contributes to radio and television.

Andrew S. French (1943-) was born in Holbeton, UK. He studied chemistry at the Universities of Salford and Essex and received a PhD in chemistry from the University of Essex in 1968, supervised by John N. Bradley. For postdoctoral training he joined the laboratory of Richard Stein at the University of Alberta. There, he soon moved through the ranks to full professor of physiology in 1982, interrupted only by a sabbatical at the Australian National University. In 1993, he became professor and head of the Department of Physiology and Biophysics at Dalhousie University, where he is (since 2022) professor emeritus. French’s research covers a wide range of topics related to sensory transduction and signal transmission in sensory systems, in particular the visual system of insects and mechanosensory system of insects and spiders. In his studies he characterizes ion channels involved in signal transduction, the role of neurotransmitters, as well as the information content of sensory channels. From 1989–90, he served as president of the Canadian Physiological Society and in 2009 received an honorary doctorate from the University of Oulu. Of his nearly 200 published journal articles and more than 20 book chapters, 21 papers on phototransduction in cockroaches and flies, and signal transduction in spider and cockroach mechanoreceptors, among other topics, appeared in JCPA.

W. Otto Friesen (1942-) was born in Elbing, Germany. After immigrating to the United States, he received his BA from Bethel College in 1964, his MA from the University of California Berkeley in 1966, and his PhD from the University of California San Diego in 1974. From 1974–77, he worked as a postdoctoral research associate in the laboratory of Gunther S. Stent* at the University of California Berkeley, where he identified a network of bilaterally paired, rhythmically active interneurons as components of the central pattern generator (CPG) that controls the swimming rhythm in the medicinal leech. He and Stent showed that recurrent cyclic inhibition plays a key role in the generation of the rhythmic neural burst activity of this CPG. In 1977, Friesen established his own laboratory at the University of Virginia, where he progressed through the faculty ranks to full professor. There, he continued to study neural mechanisms underlying rhythmic locomotion in the medicinal leech, including how swimming is modulated by sensory input. Friesen retired in 2013. Out of the 56 original papers that he published during his career, 22 appeared in JCPA.

James Howard Fullard (1952–2010) was born in British Columbia. He was an undergraduate the University of Toronto (1971–75) where he worked with Glenn K. Morris on the biology of insect auditory systems. He then moved to Carleton University where he received his master’s (1976) and his PhD (1979) degrees, on the topic of sound production in tiger moths, under the mentorship of M. Brock Fenton. He conducted postdoctoral research with Morris at the University of Toronto and with James A. Simmons at the University of Oregon. Fullard joined the faculty at the University of Toronto (1980), where he rose through the ranks to full professor (1993) and where he remained until his death. The James H. Fullard Nature Trial, near the Queen’s University Biological Station, was named in his memory. Over his career, Fullard travelled extensively throughout the tropics to conduct field work on insects and bat-insect interactions. Among his approximately 100 original research articles, he published 19 papers in JCPA. These papers describe in detail the auditory sensitivity of insects (tympanate moths, crickets) on the basis of acoustic, behavioral, and physiological measurements, and the behavioral strategies that have evolved in these species to avoid predation by echolocating bats.

Howard Carl Gerhardt (1945-) was born in Newport News, Virginia and grew up in Savannah, Georgia. He received his Bachelor of Science in zoology at the University of Georgia in 1966, and his PhD from the University of Texas at Austin in 1970. From 1970–71, he was a postdoctoral researcher with Robert R. Capranica* at Cornell University studying the neurobiology and behavior of amphibians. In 1971, he was appointed as an assistant professor at the University of Missouri, where he progressed through the faculty ranks to full professor. He is now a Curators’ Distinguished Professor Emeritus of Biological Sciences. Gerhardt received many honors and awards including the Senior Humboldt Award (1995), the Frank Beach Award (2001), the Distinguished Herpetologist Award from the Herpetologist League (2006), the Thomas Jefferson Award of the University of Missouri (2012), and the Quest Award from the Animal Behavior Society (2015). He is a Fellow of the Animal Behavior Society (elected 1991) and of the American Association for the Advancement of Science (1998). Gerhardt has contributed significantly to the understanding of the evolution and neurobiology of acoustic communication in amphibians. He identified the pertinent properties of male calls that are used by females for mate choice. By systematically varying the acoustic properties of synthetic sounds that mimic the stereotyped calls of males and by measuring the responses of females, he found that female grey treefrogs prefer the calls that are the most energetically expensive for the males to produce. This allows females to ensure that the male they select is not only in good physical condition, but also possibly genetically better than his neighbors. He co-authored with Franz Huber* the book Acoustic Communication in Insects and Anurans (Chicago University Press, 2002). Of the 207 publications (including books and book chapters) produced by Gerhardt, 20 highly cited papers appeared in JCPA.

Martin Giurfa (1962-, born in Lima) is a well-known neuroethologist and a pioneer in the field of insect cognition, with a special interest in the cognitive abilities of bees. Following an undergraduate degree in biology at the University of Buenos Aires, Giurfa obtained a PhD at the same university under the supervision of Josué Núñez. In 1990, he joined the laboratory of Randolf Menzel* at the Free University in Berlin where he built a reputation for his studies on color vision of bees. He obtained the Habilitation from the Free University of Berlin in 1997, and became assistant professor in the Institute of Neurobiology there. In 2001, Giurfa became professor of neuroscience at Paul Sabatier University in Toulouse where he continued his research on insect cognition. Since 2023, he has been Exceptional-Class Professor of Neurosciences at the Sorbonne University. He has been the