In a previous study, Puk and Stibbards (2010) demonstrated that a cohort of teacher candidates entering into an ecological literacy, Bachelor of Education program had very immature understanding of complex ecological concepts. Specifically, written definitions were either absent entirely, very vague, or missing essential criterial attributes, as well as lacking consistency in terms of their meanings. The current study was conducted at the end of the program with the same cohort and concepts in order to determine the effect that the innovative, emergent learning approach taken in this program had on teacher candidates' ability to define these concepts and their growth in conceptual understanding of these concepts from pre-course to post-course. The preservice course in ecological literacy in which these teacher candidates were enrolled featured dynamic, embodied activities that seek to promote deep understanding of the complexity found in the intersections between natural systems and human systems. The current study found that there was significant growth in developing more mature definitions of key ecological concepts, which is attributed in part to the use of these emergent instructional activities. In addition, teacher candidates expressed a new, discerning approach to the general usage of some of the concepts as demonstrated by their critical assessment of their own definitions. The findings suggest that growth in ecological concept development and conceptual understanding for teacher candidates can be achieved through the use of nature-embedded, embodied experience. (Contains 3 figures and 2 tables.)