The Adaptation Process Of Ceratitis Capitata To The Laboratory Analysis Of Life-history Traits

Colonizing species are believed to have genetic plasticity that permits their adaptation to new habitats. The Mediterranean fruit fly, Ceratitis capitata, is known for this ability, reflected in its present world-wide geographical distribution. To investigate the genetic components of the colonizing capacity of this species, we studied the life-table parameters in (a) a recently-collected wild population, (b) a laboratory strain maintained for 6 years, and (c) a hybrid population resulting from crosses between the wild females and long-term laboratory maintained males. All the strain were collected in the same host and place. Within a few generations, both the hybrid and the wild strains showed life table parameters (egg, larval, pupal and adult mortalities, net reproductive rate, intrinsic rate of population growth, and generation time) similar to those of the laboratory strain. A difference in the speed of adaptation to the laboratory conditions was remarkable, with the hybrid population reaching the values of the long-term laboratory strain much faster than the wild population. An incipient reproductive isolation between the laboratory and the wild population was also observed. The genetic plasticity that allows fast adaptation to new conditions such as those in the laboratory is high in C. capitata, although the genetical variability measured by enzyme electrophoresis in Brazilian populations is low. This suggests that the isozyme variation observed is not related to this kind of adaptation. © 1988 Kluwer Academic Publishers.49319520

Allozymic Variability In Natural Silba Spp. Populations (diptera: Lonchaeidae)

[No abstract available]7341943

Structural control and geochronology of Cretaceous carbonate breccia pipes, Crato Formation, Araripe Basin, NE Brazil

The laminated limestones of the Crato Formation, Araripe Basin (NE of Brazil) have been investigated, as they are analogous to facies of the carbonate reservoirs of the pre-salt sequence of the Brazilian marginal basins. The Early Cretaceous Crato laminites comprise a complex range of structures that may play an important role in the porosity and permeability distribution in carbonate reservoirs. This work aims to (1) understand the control of a boundary fault zone (the Triunfo Fault, Lower Cretaceous) on the development in carbonate breccia pipes of the Crato Formation, and (2) constrain the timing of brittle deformation, based on field observations, microstructural investigation and U–Pb carbonate geochronology. The breccia pipes are observed surrounding both normal and strike-slip faults. The brittle deformation superimposed on the pipes is characterized by brecciation and veining that show multiples phases of mineralization. Our results propose the circulation of fluid along the pre-existing faults and pipes, these fluids are responsible for polyphasic deformation in the pipes. We report two U–Pb ages from carbonate-vein mineralization of 94.9 ± 3.8 Ma (Cenomanian to Turonian) and 80.2 ± 3.0 Ma (2σ) (Campanian), which provide time constraints on the brittle reactivations of the Triunfo Fault Zone, during the post-rift phase of the Araripe Basin