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Roy Caldwell
Curator/Professor, Integrative Biology

Roy Caldwell


Phone: (510) 642-1391

Web page:

His research: Roy studies the behavior of stomatopods, marine crustaceans that are distantly related to shrimp. Roy has been studying stomatopods for over 40 years; at this point, he says, "the animals themselves start asking the questions." These days, Roy is focused on how stomatopods use polarized light to communicate with each other.

His path to the UCMP: Roy is an animal behaviorist and marine biologist — it is a bit unusual for a biologist with his background to be involved with a paleontology museum. However, the UCMP has a large collection of marine invertebrate specimens, some of which are fossils and some of which are modern. Roy has collected many marine invertebrate specimens, including cephalopods and stomatopods, while doing field work in Indonesia and French Polynesia. He contributed these specimens to the UCMP's collections and became a faculty curator. Roy's contributions to the museum don't stop there. "I have an interest in evolution outreach and public education," he says. Roy is the principal investigator on the UCMP's Understanding Evolution and Understanding Science websites.


Caldwell, R.L., R. Ross, A. Rodaniche and C.L. Huffard. 2015. Behavior and Body Patterns of the Larger Pacific Striped Octopus. PLOS ONE, DO1L10,1371 1-17.

Vetter, K.M. and R.L. Caldwell. 2015. Individual recognition in stomatopods. In: Social Recognition in Invertebrates. L. Aquiloni and E. Tricarico, eds. Springer.

Dougherty, L.F., S. Johnsen, R.L. Caldwell, N.J. Marshall. 2014. A dynamic broadband reflector built from microscopic silica spheres in the 'disco' clam Ctenoides ales. J. R. Soc. Interface 11: 20140407. Notes: Metrics: Altmetric has tracked 2,487,155 articles across all journals so far. Compared to these, this article has done particularly well and is in the 99th percentile: it's in the top 5% of all articles ever tracked by Altmetric. More info and metrics:   Read it

Caldwell, R.L. 2013. Keeping zebra mantis shrimp: Part 2. Coral Magazine, Jan.-Feb., 74-82.

Caldwell, R.L. 2013. A Wunderpus adventure. Coral Magazine, May-June, 71-78.

Glenn, D., M.J. Pakes, and R.L. Caldwell. 2013. Fluorescence in Arthropoda informs ecological studies in anchialine crustaceans, Remipedia and Atyidae. Journal of Crustacean Biology 33:620-626.

Porter, M.L., D.I. Speiser, A.K. Zaharoff, R.L. Caldwell, T. W. Cronin, and T.H. Oakley. 2013. The evolution of complexity in the visual systems of stomatopods: Insights from transcriptomics. Integrative and Comparative Biology 53:39-49.

Caldwell, R.L. 2012. Keeping zebra mantis shrimp: Part 1. Coral Magazine, Nov.-Dec, 84-93.

Campos, E. O., D. Vihena, and R. L. Caldwell. 2012. Pleopod rowing is used to achieve high forward swimming speeds during the escape response of Odontodactylus havanensis (Stomatopoda). Journal of Crustacean Biology 32:171-179.

Chiou, T.-H., A.R. Place, R.L. Caldwell, J. Marshall, and T.W. Cronin. 2012. A novel function for a carotenoid: Astaxanthin used as a polarizer for visual signalling in a mantis shrimp. Journal of Experimental Biology 215:584-589.

Williams, B.L., M. Stark, and R.L. Caldwell. 2012. Microdistribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena lunulata and Hapalochlaena fasciata) detected by fluorescent immunolabeling. Toxicon 60:1307-1313.

Chiou, T.-H., N.J. Marshall, R.L. Caldwell, and T.W. Cronin. 2011. Changes in light reflecting properties of signalling appendages alter mate choice behaviour in a stomatopod crustacean Haptosquilla trispinosa. Marine and Freshwater Behaviour and Physiology 44(1):1-11. doi: 10.1080/10236244.2010.546064

Thanukos, A., J.G. Scotchmoor, R. Caldwell, and D.R. Lindberg. 2010. Science 101: Building the foundations for real understanding. Science 330:1764-1765.

Bush, S.L., B.H. Robison, and R.L. Caldwell. 2009. Behaving in the dark: Locomotor, chromatic, postural and bioluminescent behaviors of the deep-sea squid Octopoteuthis deletion Young 1972. Biological Bulletin 216:7-22.  Read it

Cheroske, A.G., T.W. Cronin, M.F. Kaminski, and R.L. Caldwell. 2009. Adaptive signaling behaviour in stomatopods under varying light conditions. Marine and Freshwater Behaviour and Physiology 42:219-232.

Cronin, T.W., T. Chiou, R.L. Caldwell, N. Roberts, and J. Marshall. 2009. Polarization signals in mantis shrimps. Proceedings of SPIE 7461:74610C.

Williams B.L., and R.L. Caldwell. 2009. Intra-organismal distribution of tetrodotoxin in two species of blue-ringed octopuses (Hapalochlaena fasciata and H. lunulata). Toxicon 54:345-353.  Read it

Chiou, T.H, R.L. Caldwell, R.T. Hanlon, and T.W. Cronin. 2008. Fine structure and optical properties of biological polarizers in crustaceans and cephalopods. Proceedings of SPIE 6972:1-10.

Chiou, T.H, S. Kleinlogel, T. Cronin, R. Caldwell, B. Loeffler, A. Siddiqui, A. Goldizen, and J. Marshall. 2008. Circular polarisation vision in a stomatopod crustacean. Current Biology 18:429-434.

Huffard, C.L., R.L. Caldwell, and F. Boneka. 2008. Mating behavior of Abdopus aculeatus (d'Orbigny 1834) (Cephalopoda: Octopodidae) in the wild. Marine Biology 154:353-362.

Huffard, C.L., R.L. Caldwell, N. DeLoach, D.W. Gentry, P. Humann, B. MacDonald, B. Moore, R. Ross, T. Uno, and S. Wong. 2008. Individually unique body color patterns in octopus (Wunderpus photogenicus) allow for photoidentification. PLoS ONE 3:e3732 1-5.

Meunier, F.J., M.V. Erdmann, Y. Fermon, and R.L. Caldwell. 2008. Can the comparative study of the morphology and histology of the scales of Latimeria menadoensis and L. chalumnae (Sarcopterygii: Actinistia, Coelacanthidae) bring new insight on the taxonomy and the biogeography of recent coelacanthids? Geological Society, London, Special Publications; v. 295; p. 351-360. doi:10.1144/SP295.17

Patek, S.N., B.N. Nowroozi, J.E. Baio, R.L. Caldwell, and A.P. Summers. 2007. Linkage mechanics and power amplification of the mantis shrimp's raptorial strike. Journal of Experimental Biology 210:3677-3688.  Read it

Fox, H.E., and R.L. Caldwell. 2006. Recovery from blast fishing on coral reefs: A tale of two scales. Ecological Applications 16:1631-1635.  Read it

Patek, S.N., and R.L. Caldwell. 2006. The stomatopod rumble: Sound production in Hemisquilla californiensis. Marine and Freshwater Behaviour and Physiology 39:99-111.

Caldwell, R.L. 2005. An observation of inking behaviour protecting adult Octopus bocki from predation by Green Turtle (Chelonia mydas) hatchlings. Pacific Science 59:69-72.

Fox, H.E., P.J. Mous, J.S. Pet, A.H. Muljadi, and R.L. Caldwell. 2005. Experimental assessment of coral reef rehabilitation following blast fishing. Conservation Biology 19:98-107.

Patek, S.N., and R.L. Caldwell. 2005. Extreme impact and cavitation forces of a biological hammer: Strike forces of the peacock mantis shrimp (Odontodactylus scyllarus). Journal of Experimental Biology 208:3655-3664.