. Atoll research bulletin. Coral reefs and islands; Marine biology; Marine sciences. Hwang et al., 2001 Chelicerata Myriapoda Crustacea. Hexapoda Giribet et al., 2001 Figure 2. Current hypotheses regarding the Crustacean-Insect relationship. (A) The 'Pancrustacea' hypothesis places the hexapod lineage within the Crustacea. Under this scenario current morphologic classification schemes of the Crustacea are paraphyletic and are grades. The monophyletic Pancrustacea presents the hexapods as a terrestrialized branch of crustaceans. Data from Hwang et al., 2001 suggests that the more basal Myriapod
. Atoll research bulletin. Coral reefs and islands; Marine biology; Marine sciences. Hwang et al., 2001 Chelicerata Myriapoda Crustacea. Hexapoda Giribet et al., 2001 Figure 2. Current hypotheses regarding the Crustacean-Insect relationship. (A) The 'Pancrustacea' hypothesis places the hexapod lineage within the Crustacea. Under this scenario current morphologic classification schemes of the Crustacea are paraphyletic and are grades. The monophyletic Pancrustacea presents the hexapods as a terrestrialized branch of crustaceans. Data from Hwang et al., 2001 suggests that the more basal Myriapoda and Chelicerata are sister taxa. (B) The competing hypothesis suggests current classification schemes correctly identify a monophyletic Crustacea. Data from Giribet et al., 2001 suggests that the Crustacea and Hexapoda are sister taxa. Their work places the Myriapoda + Crustacea + Hexapoda in a monophyletic clade with chelicerates as the basal outgroup. Crustacean Appendages: comparative morphology meets comparative gene expression The Crustacea largely interact with their environment via their appendages; thus vast amounts of variation exist between the different appendages of a single individual as well as between appendages from different species. Comparative studies of crustacean appendage development present an important story regarding the evolution of morphology over both relatively short (a few million years) and relatively long (a few hundred million years) evolutionary time scales. Comparisons of appendage development utilizing molecular and genetic data garnered from Drosophila appendage development have been a recurrent theme in recent comparative work in an attempt to understand the molecular basis for some of the variation seen in crustacean limbs ( Williams, 1998; Nulsen and Nagy, 1999; Abzhanov and Kaufman, 2000; Browne and Patel, 2000; Williams et al., 2002).. Please note that these images are extracted from scanned page images that may have been digitall
Size: 1989px × 1256px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauth, bookauthorsmithsonianinstitutionpress, bookcentury1900
