Functional modularity in lake-dwelling characin fishes of Mexico

PeerJ

article

Claudia Patricia Ornelas-García¹  Amando Bautista²  Fabian Herder³  Ignacio Doadrio⁴ 

[1] Colección Nacional de Peces, Departamento de Zoología, Instituto de Biología, Universidad Nacional Autónoma de México;Centro Tlaxcala de Biología de la Conducta, Universidad Autónoma de Tlaxcala;Sektion Ichthyologie;Departamento de Biodiversidad y Biología Evolutiva

关键词: Modularity;    Geometric morphometrics;    Astyanax;    Trophic diversity;    Functional morphology;   

DOI  :  10.7717/peerj.3851

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Modular evolution promotes evolutionary change, allowing independent variation across morphological units. Recent studies have shown that under contrasting ecological pressures, patterns of modularity could be related to divergent evolution. The main goal of the present study was to evaluate the presence of modular evolution in two sister lacustrine species, Astyanax aeneus and A. caballeroi, which are differentiated by their trophic habits. Two different datasets were analyzed: (1) skull X-rays from 73 specimens (35 A. aeneus and 38 A. caballeroi) to characterize skull variation patterns, considering both species and sex effects. For this dataset, three different modularity hypotheses were tested, previously supported in other lacustrine divergent species; (2) a complete body shape dataset was also tested for four modularity hypotheses, which included a total of 196 individuals (110 Astyanax aeneus and 86 A. caballeroi). Skull shape showed significant differences among species and sex (P < 0.001), where Astyanax caballeroi species showed an upwardly projected mandible and larger preorbital region. For the skull dataset, the modularity hypothesis ranked first included three partitioning modules. While for the complete body dataset the best ranked hypothesis included two modules (head vs the rest of the body), being significant only for A. caballeroi.

【 授权许可】

CC BY