Clinal Variation in the Surface-Volume Relationships of the Columnar Cactus Lophocereus Schottii in Northwestern Mexico
Felger RS and Lowe CH. 1967. Clinal Variation in the Surface-Volume Relationships of the Columnar Cactus Lophocereus Schottii in Northwestern Mexico. Ecology. 48(4):530-535
Regression analysis of clines in the surface-volume ratios of stems of the columnar cactus Lophocereus schottii in Sonora, Mexico, reveals similar relationships for clinal interpopulation variation and ontogenetic intrapopulation variation. Smaller surface-volume ratios (larger, thicker stems) occur in the northern parts of the distributions of Lophocereus and the othe large columnar species; the younger (sterile) growths of all populations also have smaller surface-volume ratios. Evolution of the surface-volume ratios of the columnar Cactaceae is discussed in relation to complex environmental gradients of temperature and moisture that characterize their effective environments in northwestern Mexico and southwestern United States.
- Type
- Journal Article
- Authors
- Felger, Richard; Lowe, Charles
- Units
- SAGU
- Keywords
- cline, columnar cactus, environmental gradients, regression analysis, Sonora Mexico, surface-volume relationship