Review and application of geometric morphometrics in aquatic animals

Abstract

Geometric morphometrics( GM) originated from late 1980s to early 1990s in last century. It differed from the traditional measurement,mainly focusing on the variability of shape. With relative theory foundation,w e w ere separating shape from size,explaining the intrinsic results using multivariate analysis. This new method w as meaningful to the organism w ith fixed and stable shape,and also w idely used in many fields. Generally,aquatic animals w ere surrounded by hard structures w ith relatively invariable shape. Meanw hile,they played different important roles in diversified w aters. This paper review ed the shape analysis of aquatic animals w ith geometric morphometrics in the recent decades,briefly described the developing process of this new method,explained the principles of outline and landmark method,and introduced methodology and some relevant softw are. Then w e retrospected the application of invertebrate and vertebrate morphological shape in aquatic area. The result show ed that this new approach w as accepted by many researchers at home and abroad,but had a limitation in species identification and population division,so w e should use the hard structures to analyze the morphological variation,consider the implication of environmental change w ith the morphology of organism,and try to print out the original appearance in 3D and describe the shape variation w ith theoretical studies.