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Coss Research Lab

UCD: Coss Research Lab

Fig. 1. Juvenile California ground squirrel throws substrate at an approaching northern Pacific rattlesnake. Photograph by John A. L. Cooke published in: Coss, R. G. and Owings, D. H.(1989). Rattler battlers. Natural History 5, 30-35. Substrate throwing is a phylogenetically old motor pattern used to spur rattlesnakes and gopher snakes into striking, rattling, or hissing. California ground squirrels can innately distinguish rattlesnakes from gopher snakes via snake odors and defensive behavior. Further information on this topic can be found in: Coss, R. G., Gusé, K. L., Poran, N. S., and Smith D. G. (1993). Development of antisnake defenses in California ground squirrels (Spermophilus beecheyi): II. Microevolutionary effects of relaxed selection from rattlesnakes. Behaviour 124, 137-164.
Fig. 2. A model red-tailed hawk is launched from a mobile tower to examine whether California ground squirrels can distinguish this dangerous raptor from crow and turkey vulture models characterizing large birds that are not predatory threats. This research revealed that, irrespective of model type, targeted juvenile and adult ground squirrels fled to their burrows after spotting these models in a descending trajectory oblique to their feeding stations. For more details, see: Hanson, M. T. and Coss, R. G. (in press). Age differences in the response of California ground squirrels (Spermophilus beecheyi) to avian and mammalian predators. Journal of Comparative Psychology.






 Fig. 3. Photomontage illustration of a vigilant Australopithecus afarensis female seeking refuge from predators in a tree for the night. Females retained a greater number of arboreal adaptations than larger-bodied males, a finding suggesting that males were less adept climbers and spent much more time on the ground than females.  In modern humans, behavioral and morphological relics of this Pliocene "sexual dinichism" are evident in the differential flexibility expressed in gymnastics and the behavioral propensity to climb playground structures safely as children.  Cognitive evidence for ancestral sexual dinichism in antipredator behavior is apparent in preschool  children who are asked to climb silhouettes of trees to seek refuge from a "lion" and to describe the spatial location of scary things in their bedrooms at night. For a general review, see: Coss, R. G. and Goldthwaite, R. O. (1995). The persistence of old designs for perception. In N. S. Thompson (Ed.), Perspectives in ethology 11: Behavioral design, Plenum Press, New York, pp. 83-148.
Fig. 4. Scenic view of mountains in Patagonia, Argentina. This photograph by former graduate student, Dr. John McNutt, characterizes many of the traits of safe open habitat with water that received high ratings in extensive preference research supported by a grant from the National Aeronautics and Space Administration's space station program. Human factors research on the effects of lighting on body orientation (Barbour, C. G. and Coss, R. G. 1988.  Differential color brightness as a body orientation cue.
Human Factors 30(6), 713-717) was used was used by NASA to specify the interior lighting for the international space station currently under construction. More detail on landscape perception, including the effects of animals on viewer arousal, can be obtained in: Coss, R. G. and Towers, S. R. (1990). Provocative aspects of pictures of animals in confined settings. Anthrozoös 3, 162-170; Coss, R. G. and Moore, M. (1990). All that glistens: Water connotations in surface finishes. Ecological Psychology 2, 367-380; Clearwater, Y. A. and Coss, R. G. (1991). Functional aesthetics to enhance well-being in isolated and confined settings. In A. A. Harrison, Y. A. Clearwater, and C. McKay (Eds.), The human experience in Antarctica: Applications to Life in Space. Springer-Verlag, N. Y., pp. 331-348.