Using FTA® cards to store avian blood samples for genetic studies. Their application in sex determination

FTA® cards were used for long‐term storage of avian blood samples. Blood DNA was extracted by a simple method and used in PCR for sex identification of adult and nestling Great Grey Shrikes Lanius excubitor.     

A methodological approach to assess the small mammal community diversity in the temperate rainforest of Patagonia

Assessing small mammal diversity is a common procedure, which usually employs widespread standard techniques, for gathering information for a wide range of studies. Traditional methods, however, may be biased against capturing arboreal marsupials, such as Dromiciops gliroides, an endemic marsupial currently considered a rare species in the Patagonian temperate rainforest due to the low abundances reported previously. I tested a new capturing methodology to assess the small mammal diversity of an old-growth forest in Patagonia, based on a randomized and balanced design, which incorporated a combination of different trap types, bait types, and placement heights. The proposed methodology included four trap types (two for live-capturing: wire-mesh and Sherman traps, and two sign-recording traps for tracks and hair), two types of bait (banana and rolled oats), and two trap placements (ground level and 1.5–2.5 m above the ground). Trap type, bait type, and height of placement all had significantly different effects on capturing and detecting rodents or marsupials; environmental variables at the trap location also affected the ability to detect rodents and marsupials. Traditional methods used for sampling small mammals performed well for rodents but are not effective for capturing marsupials and vice versa, showing species-specific sampling protocols. There is no single combination of trap-bait-height capable to assess the entire small mammal community, but the combination of the most effective protocol for rodents and the most effective protocol for marsupials guarantee better results.     

The Identification of Congeners and Aliens by Drosophila Larvae

We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn ^97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn ^97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles.     

Biomass-size spectra in aquatic communities in shallow fluctuating Mediterranean salt marshes (Emporda wetlands, NE Spain)

The distribution of biomass among phytoplankton and free-livinginvertebrates was analysed in a shallow Mediterranean salt marshsubmitted to fluctuating water level. Among phytoplankton, biomassaccumulated in sizes dominated by mixotrophic species, indicatinga competitive advantage for these species, which also prey onother smaller primary producers. Among invertebrates, biomassaccumulated in the larger sizes, corresponding to species whichpartially exploit other nearby systems, such as the aerial environment(insects), or to those able to exploit particulated organicmatter in marsh-bed sediment (amphipods). Biomass distributionmodels developed for pelagic systems are discussed in relationto fluctuating temporary waters. The integrated spectrum approximated(r² = 0.96) a Pareto distribution with a slope of c = 1.38.Intense disturbances caused a decrease in r² and an increasein c. Under stable conditions, two different tendencies wereobserved, depending on the degree of eutrophy of the basins:higher values of c were measured in the more eutrophic basins,and lower values in the less eutrophic ones. We hypothesizethat highly irregular nutrient input could explain these differences.     

Potential long-acting contraceptive agents: esters of testosterone with alkoxy- and halogeno-substituted carboxylic acids

The chemical synthesis and physical data of several new esters of testosterone (17 beta-hydroxyandrost-4-en-3-one), which contain either a halogeno or an alkoxy substituent in the acid chain, are reported.     

The gene for trypsin inhibitor CMe is regulated in trans by the lys 3a locus in the endosperm of barley (Hordeum vulgare L.)

Summary A cDNA encoding trypsin inhibitor CMe from barley endosperm has been cloned and characterized. The longest open reading frame of the cloned cDNA codes for a typical signal peptide of 24 residues followed by a sequence which is identical to the known amino acid sequence of the inhibitor, except for an Ile/Leu substitution at position 59. Southern blot analysis of wheat-barley addition lines has shown that chromosome 3H of barley carries the gene for CMe. This protein is present at less than 2%–3% of the wild-type amount in the mature endosperm of the mutant Risø 1508 with respect to Bomi barley, from which it has been derived, and the corresponding steady state levels of the CMe mRNA are about I%. One or two copies of the CMe gene (synonym Itc1) per haploid genome have been estimated both in the wild type and in the mutant, and DNA restriction patterns are identical in both stocks, so neither a change in copy number nor a major rearrangement of the structural gene account for the markedly decreased expression. The mutation at the lys 3a locus in Risø 1508 has been previously mapped in chromosome 7 (synonym 5H). A single dose of the wild-type allele at this locus (Lys 3a) restores the expression of gene CMe (allele CMe-1) in chromosome 3H to normal levels.