From dusk till dawn: camera traps reveal the diel patterns of flower feeding by hawkmoths

1. Diel rhythms of foraging activity by animal flower visitors can reflect niche partitioning and are considered an important component of selection on floral traits. However, it has been notoriously difficult to obtain objective information on the patterns of flower visitation by crepuscular and nocturnal insects. 2. Motion-activated cameras were used for field-based studies of hawkmoth foraging behaviour on six African plant species. 3. The results showed that short-tongued hawkmoth species forage mainly around dusk and then sporadically throughout the night, whereas long-tongued hawkmoth species feed consistently throughout the night, with a peak shortly before midnight. 4. These results provide the first quantitative estimates of diel patterns of interactions between multiple hawkmoth and plant species and, when combined with qualitative reports from other studies, suggest that differences in diel activity between the two main hawkmoth functional groups (short- and long-tongued) are consistent across the Old and New Worlds.     

Evolution of the Cholecystokinin and Gastrin Peptides and Receptors

The intestinal hormone, cholecystokinin (CCK), and the stomachhormone, gastrin, form a simple two member family of peptideswith much to offer students of hormone and receptor evolution.They share a common carboxyl-terminal tetrapeptide sequence,which is the bioactive site of each peptide and is also antigenic,making heterologous biological and immunological assays feasible.Current evidence indicates that CCK evolved in chordate ancestorsand that gastrin-like peptides that separately regulate stomachfunctions evolved from an ancestral CCK at the level of thedivergence of tetrapods from fish. This tentative conclusionmay require modification when the two separate CCK- and gastrin-likepeptides recently identified in the dogfish shark are characterizedfurther. The CCK-X receptor appears to be ancestral to the CCK-Aand CCK-B receptors identified in amniotes. The evolution ofgastrin and of CCK-A and -B receptors may have played rolesin the evolution of the stomach and the evolution of endothermyin vertebrate phylogeny.     

Functional rarefaction: estimating functional diversity from field data

Studies in biodiversity-ecosystem function and conservation biology have led to the development of diversity indices that take species' functional differences into account. We identify two broad classes of indices: those that monotonically increase with species richness (MSR indices) and those that weight the contribution of each species by abundance or occurrence (weighted indices). We argue that weighted indices are easier to estimate without bias but tend to ignore information provided by rare species. Conversely, MSR indices fully incorporate information provided by rare species but are nearly always underestimated when communities are not exhaustively surveyed. This is because of the well-studied fact that additional sampling of a community may reveal previously undiscovered species. We use the rarefaction technique from species richness studies to address sample-size-induced bias when estimating functional diversity indices. Rarefaction transforms any given MSR index into a family of unbiased weighted indices, each with a different level of sensitivity to rare species. Thus rarefaction simultaneously solves the problem of bias and the problem of sensitivity to rare species. We present formulae and algorithms for conducting a functional rarefaction analysis of the two most widely cited MSR indices: functional attribute diversity (FAD) and Petchey and Gaston's functional diversity (FD). These formulae also demonstrate a relationship between three seemingly unrelated functional diversity indices: FAD, FD and Rao's quadratic entropy. Statistical theory is also provided in order to prove that all desirable statistical properties of species richness rarefaction are preserved for functional rarefaction.     

Reducing acetylated tau is neuroprotective in brain injury

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Two new species of Myxobolus Bütschli, 1882 (Cnidaria: Bivalvulida: Myxobolidae) infecting the gill of the black redhorse,Moxostoma duquesnei (Lesueur) (Cypriniformes: Catostomidae) in the Little Tennessee River Basin,North Carolina

Systematic Parasitology - Two new species of Myxobolus Bütschli, 1882 (Bivalvulida: Myxobolidae) are described from the gill of the black redhorse (Moxostoma duquesnei [Leueur][Cypriniformes:...     

Strategically Functionalized Adenosines: Agonists for Adenosine Receptors

Abstract

The syntheses of three classes of adenosine analogues involving cyclosubstitution at the 6-position and functionalization at the 2-position are reported. The target molecules synthesized are stable with respect to hydrolytic deamination by mammalian adenosine deaminase, and, because of major structural changes at the 2- and 6-positions, these compounds are expected to be poor phosphorylation substrates for the kinases. Adenosine receptor binding data reveal that several of the compounds synthesized show excellent A₁ receptor affinity and A₂/A₁ selectivity.