Papers in the Biological Sciences


Date of this Version



American Midland Naturalist (July 1981) 106(1): 157-164.


Copyright 1981, University of Notre Dame. Used by permission.


The reproductive cycle of Sceloporus undulatus was studied in western Nebraska. Females mature in the 1st year following hatching at a size of 45 mm SVL. Two clutches averaging 5.5 eggs each are produced. Egg sizes are similar to other grassland populations and contain approximately 650 g-cal. per egg. Egg weight to body weight ratios of 0.33 were the highest which have been reported for any S. undulatus population. Variation in life history characteristics within and between grassland and eastern woodland habitat types are explicable given a knowledge of the growing season, predation intensity and demographic environment.