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Jon G Hall CITP FBCS says cash and data are important but not as critical as the ability to tell a good story.

ABSTRACr.-An 888-base-pair segment of the mitochondrial cytochrome-b gene was sequenced for New World barbets, Old World barbets, toucans, and several outgroup taxa. Toucans were consistently identified as the sister taxon of the New World barbets by a variety of analyses. These data are fundamentally different from earlier morphological analyses and the DNA-DNA hybridization study of these same taxa. Our results provide an independent confirmation of relationships proposed in both the morphological and molecular studiesthat New World barbets and toucans are sister taxa with respect to Old World barbets. Received 19 June 1992, accepted 25 November 1992. TRADITIONAL MORPHOLOGICAL analyses have disagreed on the phylogenetic relationships among the barbets (Capitonidae), a pantropical assemblage of frugivorous birds, traditionally placed in the Piciformes with woodpeckers

Homologues of glucosephosphate isomerase (GPI, EC 5.3.1.9) were purified to homogeneity and kinetically characterized from Mytilus edulis and Isognomon alatus, two bivalve molluscs experiencing contrasting thermal environments. The enzyme isolated from I. alatus functions at warmer temperatures (25-35 C) than GPI from M. edulis, a species that inhabits colder marine littoral habitats (5-20 C). The former exhibits apparent first-order (with respect to substrate) catalytic rate constants ( Vm,,/KM) in vitro that become progressively greater than the mussel enzyme as the assay temperature is raised. Apparent zero-order catalytic rate constants (I’,,,) are relatively less differentiated. Catalytic efficiency, defined as the rate at which a catalytic event occurs in either reaction direction for reference standard states (substrate concentrations), is greater for the enzyme from the tropical species (I. alatus) at all realistic combinations of temperature and substrate concentration except for the lowest temperatures and highest substrate concentrations, where the GPI from the boreal/temperate M. edulis is more efficient. This pattern of catalytic divergence appears to be due primarily to differentiation in V,,,/K, . These results and other published data are reviewed and shown to be inconsistent with claims that adaptation of enzymes to higher cell temperatures requires a loss in catalytic efficiency.