prof. dr. H. (Hal) Caswell
Faculty of Science
Institute for Biodiversity and Ecosystem Dynamics
Science Park A
Science Park 904 Room number: C6.161
1090 GE Amsterdam
My research focuses on population models, usually based on matrices, for plants, animals, and humans. I am interested in stochastic processes in demography, including individual stochasticity (random outcomes of individual lives, affecting indices such as longevity), demographic stochasticity (random growth of populations generated by the stochastic outcomes of survival and reproduction), and environmental stochasticity (fluctuations in the vital rates that affect all members of the population). I study both basic theory and the application of that theory, especially to evolutionary questions and to environmental questions related to climate change.
Beyond individuals, it is notable that family dynamics are important for the life histories of humans and of some kinds of animals: primates, whales, some birds, and social insects in particular. Matrix population models may provide an important analytical tool to explore the patterns of kinship and family structures implied by particular sets of demographic processes.
You can download a CV with a complete list of publications here.
Some of the projects I am currently involved in:
- Stochasticity and heterogeneity in lifetime reproductive output. Using Markov chains with rewards to calculate the variance in lifetime reproductive output that is implied by any set of age- or stage-specific demographic rates, without the need to invoke individual heterogeneity. Comparisons across species and in historical series of human populations.
- Eco-evolutionary dynamics. Combining ecological and demographic processes, using matrix population models, with evolutionary dynamics at the level of single-locus Mendelian genetics.
- Mathematics of demographic models and Markov chains. Developing comprehensive mathematical treatments of second-order demographic models, ageXstage-classified models, cause of death analyses, and properties of multistate Markov chains.
- Matrix approaches to health demography. Using matrices to incorporate both prevalence-based and incidence-based models for healthy longevity. Focusing on extending results from a preoccupation with means to inclusion of variances and higher moments.
- Matrix methods for the analysis of family and kinship structures.
- Sensitivity analysis in ecology and demography. Any population model implies a relationship between the parameter values and the outcomes of the model. Sensitivity analysis attempts to determine how changes in the parameters would translate into changes in the outcomes. I am applying matrix calculus methods to carry out sensitivity analysis of population projections, demographic variances, second-order demographic models, ageXstage-classified models, and models for cause of death.
- Seabird ecology. In collaboration with researchers at Woods Hole Oceanographic Institution, I am working on demographic models for Antarctic seabirds (fulmars, albatrosses) with a focus on identifying and projecting effects of climate change.
- A matrix formulation of the analysis of causes of death. Organisms, including humans, are subject to a variety of causes of death. These causes are competing risks, because while the individual is at risk from all of them, only one can, in the end, be the cause of death. There is a long tradition of calculating the results of competing risks; this project is using matrix methods to carry out all the traditional analyses and more.
- Jenouvrier, S., Aubry, L. M., Barbraud, C., Weimerskirch, H., & Caswell, H. (2018). Interacting effects of unobserved heterogeneity and individual stochasticity in the life history of the southern fulmar. Journal of Animal Ecology, 87(1), 212-222. DOI: 10.1111/1365-2656.12752 [details]
- Caswell, H., & Vindenes, Y. (in press). Demographic variance in heterogeneous populations: matrix models and sensitivity analysis. Oikos, 127, 648-663.
- Roth, G., & Caswell, H. (in press). Occupancy time in sets of states for demographic models. Theoretical Population Biology, 120, 62-77.
- Hamel, S., Yoccoz, N. G., Gaillard, J-M., Bassar, R. D., Bouwhuis, S., Caswell, H., ... Vindenes, Y. (in press). General conclusion to the special issue Moving forward on individual heterogeneity. Oikos. DOI: doi: 10.1111/oik.05223
- de Vries, C., & Caswell, H. (2017). Demography when history matters: construction and analysis of second-order matrix population models. Theoretical Ecology, 1-12. DOI: 10.1007/s12080-017-0353-0
- Ackleh, A. S., Chiquet, R. A., Ma, B., Tang, T., Caswell, H., Veprauskas, A., & Sidorovskaia, N. (2017). Analysis of lethal and sublethal impacts of environmental disasters on sperm whales using stochastic modeling. Ecotoxicology, 26(6), 820–830. DOI: 10.1007/s10646-017-1813-4 [details]
- Hartemink, N., Missov, T. I., & Caswell, H. (2017). Stochasticity, heterogeneity, and variance in longevity in human populations. Theoretical Population Biology, 114, 107-116. DOI: 10.1016/j.tpb.2017.01.001 [details]
- Smallegange, I. M., Caswell, H., Toorians, M. E. M., & de Roos, A. M. (2017). Mechanistic description of population dynamics using dynamic energy budget theory incorporated into integral projection models. Methods in Ecology and Evolution, 8(2), 146-154. DOI: 10.1111/2041-210X.12675 [details]
- Caswell, H. (2017). Dynamics of leprosy in Nine-Banded Armadillos: Net reproductive number and effects on host population dynamics. Ecological Modelling, 350, 100-108. DOI: 10.1016/j.ecolmodel.2017.02.001
- Caswell, H., & Shyu, E. (2017). Senescence, selection gradients and mortality. In R. P. Shefferson, O. R. Jones, & R. Salguero-Gómez (Eds.), The Evolution of Senescence in the Tree of Life (pp. 56-82). Cambridge: Cambridge University Press. DOI: 10.1017/9781139939867.004 [details]
- Caswell, H., & van Daalen, S. F. (2017). Lifetime reproductive output: individual stochasticity, variance, and sensitivity analysis. Theoretical Ecology, 10, 355-374. DOI: 10.1007/s12080-017-0335-2
- Hartemink, N. A., & Caswell, H. (in press). Variance in animal longevity: contributions of heterogeneity and stochasticity. Population Ecology.
- Shyu, E., & Caswell, H. (in press). Matings, births, and transitions: a new two-sex matrix model for evolutionary demography. Population Ecology.
- Koons, D. N., Iles, D. T., Schaub, M., & Caswell, H. (2016). A life-history perspective on the demographic drivers of structured population dynamics in changing environments. Ecology Letters, 19(9), 1023-1031. DOI: 10.1111/ele.12628 [details]
- Shyu, E., & Caswell, H. (2016). A demographic model for sex ratio evolution and the effects of sex-biased offspring costs. Ecology and Evolution, 6(5), 1470-1492. DOI: 10.1002/ece3.1902 [details]
- Caswell, H., & van Daalen, S. F. (2016). A note on the vec operator applied to unbalanced block matrices. Journal of applied mathematics. DOI: 10.1155/2016/4590817
- Roth, G., & Caswell, H. (2016). Hyperstate matrix models: extending demographic state spaces to higher dimensions. Methods in Ecology and Evolution, 7(12), 1438-1450. DOI: 10.1111/2041-210X.12622 [details]
- Salguero-Gómez, R., Jones, O. R., Archer, C. R., Bein, C., de Buhr, H., Farack, C., ... Vaupel, J. W. (2016). COMADRE: a global database of animal demography. Journal of Animal Ecology, 85(2), 371-384. DOI: 10.1111/1365-2656.12482 [details]
- Shyu, E., & Caswell, H. (2016). Frequency-dependent two-sex models: a new approach to sex ratio evolution with multiple maternal conditions. Ecology and Evolution, 6(19), 6855-6879. DOI: 10.1002/ece3.2202 [details]
- Wensink, M., Caswell, H., & Baudisch, A. (2016). The rarity of survival to old age does not drive the evolution of senescence. Evolutionary Biology. DOI: 10.1007/s11692-016-9385-4
- Caswell, H., & Kluge, F. A. (2015). Demography and the statistics of lifetime economic transfers under individual stochasticity. Demographic Research, 32, 563-588. . DOI: 10.4054/DemRes.2015.32.19 [details]
- Caswell, H., & Sánchez Gassen, N. (2015). The sensitivity analysis of population projections. Demographic Research, 33, 801-840. . DOI: 10.4054/DemRes.2015.33.28 [details]
- van Daalen, S., & Caswell, H. (2015). Lifetime reproduction and the second demographic transition: Stochasticity and individual variation. Demographic Research, 33, 561-588. . DOI: 10.4054/DemRes.2015.33.20 [details]
- Caswell, H. (2014). A matrix approach to the statistics of longevity in heterogeneous frailty models. Demographic Research, 31, 553-592. DOI: 10.4054/DemRes.2014.31.19 [details]
- Engelman, M., Caswell, H., & Agree, E. M. (2014). Why do lifespan variability trends for the young and old diverge? A perturbation analysis. Demographic Research, 30, 1367-1396. . DOI: 10.4054/DemRes.2014.30.48 [details]
- Jenouvrier, S., Holland, M., Stroeve, J., Serreze, M., Barbraud, C., Weimerskirch, H., & Caswell, H. (2014). Projected continent-wide declines of the emperor penguin under climate change. Nature Climate Change, 4, 715-718. DOI: 10.1038/NCLIMATE2280 [details]
- Salguero-Gómez, R., Jones, O. R., Archer, C. R., Buckley, Y. M., Che-Castaldo, J., Caswell, H., ... Vaupel, J. W. (2014). The COMPADRE plant matrix database: an open online repository for plant demography. Journal of Ecology, 103(1), 202-218. DOI: 10.1111/1365-2745.12334 [details]
- Shyu, E., & Caswell, H. (2014). Calculating second derivatives of population growth rates for ecology and evolution. Methods in Ecology and Evolution, 5(5), 473-482. DOI: 10.1111/2041-210X.12179 [details]
- Caswell, Hal (2000-2017): Elected member, American Academy of Arts and Sciences, American Academy of Arts and Sciences.
Talk / presentation
- Caswell, Hal (speaker) (7-2017): Matrix population models: from the individual to the population, International Linear Algebra Society, Ames, Iowa, United States.
- de Vries, Lotte (speaker) & Caswell, H. (speaker) (15-2-2017): A genetic matrix population model for eco-evolutionary dynamics., Netherlands Annual Ecological Meeting, Lunteren.
- Ouellete, Nadine (speaker) & Caswell, Hal (speaker) (9-2016): Mortality and causes of death: matrix formulation and sensitivity analysis, European Population Conference 2016, Mainz, Germany.
- Sanchez Gassen, N.E. (speaker) & Caswell, Hal (speaker) (9-2016): The sensitivity and elasticity analysis of multistate population projections., European Population Conference 2016, Mainz, Germany.
- Caswell, Hal (speaker) (6-2016): The contribution of individual stochasticity to variance in fitness components, Paris Workshop on Fitness and Adaptation 2016, Paris, France.
- Sanchez Gassen, N.E. (speaker) & Caswell, Hal (speaker) (5-2016): Projecting population ageing and population decline in Europe, 2013-2080: Estimating the sensitivity and elasticity of projection results, Annual Meeting 2016, Population Association of America, San Diego, CA, San Diego, United States.
- Hartemink, N.A. (speaker) & Caswell, Hal (speaker) (5-2016): Matrix models for heterogeneous frailty: partitioning the variance in longevity., Annual meeting of the NVTB (dutch society for theoretical biology), Schoorl, Netherlands.
- van Daalen, S.F. (speaker) & Caswell, Hal (speaker) (11-2015): The mean, variance, and other statistics of lifetime reproduction implied by the mortality and fertility schedules in developed countries., Dutch Demography Society, Utrecht, Netherlands.
- Sanchez Gassen, N.E. (speaker) & Caswell, Hal (speaker) (11-2015): Population ageing and population decline in Europe, 2013-2080: Estimating the sensitivity and elasticity of projection results, Dutch Demography Society, Utrecht, Netherlands.
- Hartemink, N.A. (speaker), Missov, Trifon (speaker) & Caswell, Hal (speaker) (11-2015): Matrix models for heterogeneous frailty: partitioning the variance in longevity, Dutch Demography Society, Utrecht, Netherlands.
- Caswell, Hal (speaker) (10-2015): How heterogeneity works: an outline of a general demographic theory, Evolutionary Demography Society Annual Meeting 2015.
- de Vries, C. (speaker) & Caswell, Hal (speaker) (10-2015): Demography when history matters: a framework for investigating second-order matrix population models, Evolutionary Demography Society Annual Meeting 2015.
- van Daalen, S.F. (speaker) & Caswell, Hal (speaker) (10-2015): Variation in lifetime reproduction: individual stochasticity and heterogeneity., Evolutionary Demography Society Annual Meeting 2015.
- Hartemink, N.A. (speaker), Missov, Trifon (speaker) & Caswell, Hal (speaker) (10-2015): Patterns in frailty in human populations: a comparison between countries, sexes, and periods, Evolutionary Demography Society Annual Meeting 2015.
- Roth, G. (speaker) & Caswell, Hal (speaker) (10-2015): Introducing hypermatrix models, Evolutionary Demography Society Annual Meeting 2015.
- Caswell, Hal (organiser) (1-2016): Short course: Matrix Approaches to Health Demography (organising a conference, workshop, ...).
Woods Hole Oceanographic Institution
Emeritus Research Scholar
Stichting School of Tai Chi Chuan
Volunteer teacher of Tai Chi