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Abstract

West et al. (2001) provided a model to describe the ontogenetic growth in organisms. They claimed that this model is general for many species. They also developed other ontogenetic growth models based on this model. However, there are many questions regarding the theory of this model. It lacks the raw data from different organisms which were used to test this model. We have grown 11 different species of most common crops in northern China. Dry and wet weights were recorded 15 times during the growth season of these crops. The dry weights of these crops were used to test the ontogenetic growth model. We used the optimization method to fit the dry weight data for estimating the parameters of the ontogenetic model. We found that the ontogenetic growth model failed to explain the growth patterns of all the species used in this study. The asymptotic maximum dry weights predicted by the ontogenetic growth model were also unreliable. However, the logistic model had a good fit to the growth data, and the predicted asymptotic maximum dry weights were also reliable. The ontogenetic growth model proposed by West et al. (2001) does not have the characteristic of “generality” for crop growth. It failed to explain the growth pattern of all the crops, and it also had problems in explaining the animal growth pattern. In contrast, the logistic model showed the better fit to most of the data from animal and plant growth patterns. Therefore, the ontogenetic growth models provided by West et al. (2001) should be further checked carefully for the problems in its basic formulations.