Duarte-Neto Paulo, Rodrigues Jonas, Lessa Rosangela
Departamento de Estatstica e Informatica, Universidade Federal Rural de Pernambuco, Rua Dom Manuel de Medeiros, s/n, Dois Irmãos - CEP, 52171-900, Recife/PE, Brazil.
Departamento de Pesca e Aquicultura, Universidade Federal Rural de Pernambuco, Rua Dom Manuel de Medeiros, s/n, Dois Irmãos - CEP, 52171-900, Recife/PE, Brazil.
J Forensic Leg Med. 2019 May;64:23-27. doi: 10.1016/j.jflm.2019.03.008. Epub 2019 Mar 16.
Shark incidents in Recife, Pernambuco state (Brazil), are registered since 1992. The occurrence of those events is in a relatively small area of urban beaches of about 30 km long, making up one of the world's highest indices of shark incidents per unit of area, totaling 64 casualties, of these 24 were fatal. To mitigate shark incidents, the knowledge on shark species involved is crucial given that each species has specific usage of the habitat and dissimilar feeding strategy. Jaws of five species caught along the Pernambuco coast (Brazil), corresponded to 2 specimens of Carcharhinus acronotus, 4 specimens of C. leucas, 1 of C. limbatus, 4 of Galeocerdo curvier and 3 of Sphyrna lewini. Relative Warps Analysis was applied to enhance possible differences among jaw shapes of the studied species. The consensus configuration from the 14 images was obtained. The first two relative warps components explained 70.17% of the total observed variation. Four distinct groups were clearly observed. Three groups were formed by single species, corresponding to G. curvier, C. leucas and S. lewini, respectively, and one group formed by the combination of C. acronotus and C. limbatus. As expected, due to its peculiar skull shape, S. lewini jaws are very different from other analyzed species, thus all observed individuals of this group were found isolated from the others, considering the horizontal axis. Relative warps and curvature analyses show to be useful tools in the forensic study of shark incidents. In general, jaws shape significantly differed among species.
自1992年起，巴西伯南布哥州累西腓市便开始记录鲨鱼袭人事件。这些事件发生在约30公里长的城市海滩这一相对较小的区域内，成为世界上单位面积鲨鱼袭人事件发生率最高的地区之一，总计造成64人伤亡，其中24人死亡。为了减少鲨鱼袭人事件，了解涉及的鲨鱼种类至关重要，因为每个物种对栖息地的利用方式和觅食策略都不同。在巴西伯南布哥海岸捕获的五种鲨鱼的颌骨，分别对应2个尖吻真鲨标本、4个公牛真鲨标本、1个大斑真鲨标本、4个居氏鼬鲨标本和3个路氏双髻鲨标本。应用相对扭曲分析来增强所研究物种颌骨形状之间可能存在的差异。获得了14张图像的共识构型。前两个相对扭曲成分解释了总观测变异的70.17%。清晰地观察到四个不同的组。三个组分别由单一物种组成，分别对应居氏鼬鲨、公牛真鲨和路氏双髻鲨，还有一个组由尖吻真鲨和大斑真鲨组合而成。正如预期的那样，由于其独特的头骨形状，路氏双髻鲨的颌骨与其他分析物种有很大不同，因此从水平轴来看，该组所有观测个体都与其他个体分开。相对扭曲和曲率分析被证明是鲨鱼袭人事件法医研究中的有用工具。一般来说，不同物种的颌骨形状存在显著差异。
