Manipulative begging by parasitic cuckoo nestlings and paradoxical host behaviour

Peer reviewe

Theoretical studies of Si and GaAs surfaces and initial steps in the oxidation

Using ab initio quantum chemical methods (generalized valence bond), we examine (i) the electronic states of Si (111) and GaAs (110) surface, (ii) the relaxation of the Si (111) surface, (iii) the reconstruction of the GaAs surface, (iv) the initial steps in the chemisorption of O_2 on Si (111), and (v) the bonding of O atom to Ga and As centers

Conducta socioespacial frente a un ambiente nuevo de Pseudotropheus tropheops Regan, 1921 (Teleostei, Cichlidae)

Sociospatial behaviour of Pseudotropheus tropheopsReagan, 1921 ina new environment (Teleostei, Cichlidae).- The relationships between agonistic behaviour and spatial variables within a group of six captive inmature Pseudotropheus tropheops is studied. Data on frequency of Eghts and spatial positions are anaiysed during three periods of time within the 24 hours foiiowing modification of the medium. Three phases of social behaviour are established: 1) exploration, performed by the group in schooling; 2) development of Dominance Hierarchy, characterised by a stable and medium sized activity area; 3) dispersa], which includes a regular, territory-like, pattern of spatial distribution. Severai details of these phases are discussed.Peer reviewe

Conducta socioespacial frente a un ambiente nuevo de Pseudotropheus tropheops Regan, 1921 (Teleostei, Cichlidae)

Sociospatial behaviour of Pseudotropheus tropheopsReagan, 1921 ina new environment (Teleostei, Cichlidae).- The relationships between agonistic behaviour and spatial variables within a group of six captive inmature Pseudotropheus tropheops is studied. Data on frequency of Eghts and spatial positions are anaiysed during three periods of time within the 24 hours foiiowing modification of the medium. Three phases of social behaviour are established: 1) exploration, performed by the group in schooling; 2) development of Dominance Hierarchy, characterised by a stable and medium sized activity area; 3) dispersa], which includes a regular, territory-like, pattern of spatial distribution. Severai details of these phases are discussed.Peer reviewe

First evidence of early socialization in the Great Spotted Cuckoo (Clamator glandarius)

Peer reviewe

First evidence of early socialization in the Great Spotted Cuckoo (Clamator glandarius)

Peer reviewe

Mott insulator model of the Si(111)–(2×1) surface

Theoretical cluster calculations for the Si(111)–(2×1) surface lead to a description in which there is a singly occupied dangling bond on each surface atom. These orbitals are weakly coupled, forming a nondegenerate, nonmetallic two-dimensional Mott insulator, a description involving very strong electron correlation effects. Strong experimental support for this Mott insulator description is provided by (i) the magnitude of Si(2p) core level shifts, (ii) the dispersion of the dangling bond energy bands, and (iii) the absolute ionization potential from the dangling bond levels

Evolutionary interplay between structure, energy and epistasis in the coat protein of the phi X174 phage family

Viral capsids are structurally constrained by interactions among the amino acids (AAs) of their constituent proteins. Therefore, epistasis is expected to evolve among physically interacting sites and to influence the rates of substitution. To study the evolution of epistasis, we focused on the major structural protein of the ϕX174 phage family by first reconstructing the ancestral protein sequences of 18 species using a Bayesian statistical framework. The inferred ancestral reconstruction differed at eight AAs, for a total of 256 possible ancestral haplotypes. For each ancestral haplotype and the extant species, we estimated, in silico, the distribution of free energies and epistasis of the capsid structure. We found that free energy has not significantly increased but epistasis has. We decomposed epistasis up to fifth order and found that higher-order epistasis sometimes compensates pairwise interactions making the free energy seem additive. The dN/dS ratio is low, suggesting strong purifying selection, and that structure is under stabilizing selection. We synthesized phages carrying ancestral haplotypes of the coat protein gene and measured their fitness experimentally. Our findings indicate that stabilizing mutations can have higher fitness, and that fitness optima do not necessarily coincide with energy minima