An artificial bird nest experiment in urban environments: Lessons from a school‐based citizen science programme

Maintaining suitable vegetation within urban environments is crucial for wildlife conservation in the face of anthropogenic habitat change. Here, we report on a citizen science project, involving students from seven schools across south‐eastern Australia, that investigated the effectiveness of urban vegetation as habitat for bird nests. The ‘nest concealment hypothesis’ posits that vegetation should obscure the nest from predator detection, thus reducing the likelihood of predation. To test this, participating school‐aged citizen scientists constructed artificial nests, which were placed in garden trees within school grounds and monitored for signs of predation. We found no evidence to support the nest concealment hypothesis, with no relationship between the density of vegetation immediately surrounding a nest and its likelihood of predation (binomial model:  = 1.714, P = 0.190). It was observed that 80% of the nests experienced predation. This aligns with mounting evidence suggesting that other factors, such as olfaction and adult defence, may be more important factors in the protection of bird nests. It is important to note that artificial nests are unreliable, and therefore, the veracity of the overall conclusions is limited. However, in conducting this experiment, we demonstrate the suitability of this method as a school‐based citizen science activity. This study exemplifies that field‐based experiments can used to engage future generations with conservation science.     

The circular dichroism properties of φW-14 DNA containing α-putrescinylthymine

The circular dichroism properties of φW-14 DNA containing α-putrescinylthymine and its acetylated derivative have been examined in a number of aqueous solvents. Native φW-14 DNA exhibits a B-type CD spectrum whose characteristics do not entirely conform to what would be expected for its GC content (51%). The conformationally sensitive positive band above 260 nm has a rotational strength greater than that normally found in prokaryotic DNAs of comparable GC content, such as Escherichia coli DNA. The rotational strength of this band in the spectrum of the heat-denatured from of φW-14 DNA, however, is similar to that of heat denatured E. coli DNA. Abolition of the positive charge on the putrescine residues of native φW-14 DNA by reaction with CH₂O or by acetylation reduces the rotational strength to a level appropriate for its GC content. Increases in the electrolyte content of the solvent have the same effect, although the rotational strength of this band in φW-14 DNA does not become comparable to that of E. coli DNA until 6–7 M LiCl. Titration to pH 10.6 in solvents of modest electrolyte content, however, fails to appreciably affect the CD spectral properties of either native φW-14 DNA or the derivative in which half of the secondary and all of the primary amino groups have been acetylated. On the basis of these results we have concluded that the enhanced rotational strength of the positive band above 260 nm in the CD spectrum of φW-14 DNA is due to a conformational difference caused by an ion-pair interaction of the positively charged primary amino groups of putrescine with the phosphate backbone. The CD spectral properties, however, reveal that these differences, averaged over the entire basepair population, appear to be relatively small. The average conformation, at least in dilute aqueous solutions, seems to be an unexceptional B variant with conformational properties which would be more appropriate for a DNA of higher CG content.     

Demonstration of the chiral inversion of ibuprofen by Verticillium lecanii in non-growing cultures

Racemic ibuprofen has previously been shown to undergo metabolism by Verticillium lecanii to yield (S)-2-[4-(2-hydroxy-2-methylpropyl)phenyl] propionic acid which is enriched in the (S)-enantiomer. However, it had not been possible to elucidate whether ibuprofen or the metabolite was inverted. This paper describes the incubation of ibuprofen in non-growing cultures of V. lecanii , the results of which indicate that racemic ibuprofen is converted into a 70 : 30 (S : R) enantiomeric mixture after 6 d incubation in the absence of any metabolism. This suggests that V. lecanii could be a useful model for the investigation of the mechanism of mammalian chiral inversion of iburprofen.