Meeting Abstract
The relationship between body size and whole-organism metabolic rate is one of the best documented physiological patterns across the tree of life. However, cell size also influences metabolic rates, leading to potential interactions between body size and cell size in driving physiological function. Cell size is itself determined by genome size, thus the physical size of the genome has a potential functional, “nucleotypic” effect on organismal physiology, particularly in lineages with adequate variation in genome size. I investigate this effect in eight species of lungless salamanders (Urodela: Plethodontidae). Lungless salamanders display substantial variation in genome size relative to other vertebrates. Critically, they respire and transport water entirely through the integument. Genome and cell size variation in this group thus have direct functional consequences by modulating the structure and function of skin, the primary site of respiratory gas and water exchange. By sampling across genome size and body size variation in this group, I quantify variation in gas and water transport as a function of genome-, cell-, integument-, and whole-organism level morphological interactions to determine how morphological variation drives plethodontid physiological function.
