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Olfaction is a widespread mode of communication in mammals. The volatile organic compounds (VOCs) in biological samples such as scat and urine give them either a repellent property to warn prey or an attractant property to communicate reproductive, social, and territorial status to conspecifics. The aim of this study was to determine whether there are VOC differences in the scat of a dingo compared to that of a domestic German Shepherd Dog (GSD). We standardised the diet for 10 days and then collected scat from 14 dingoes and 11 GSDs. Using headspace solid phase microextraction (HS-SPME) with gas chromatography–mass spectrometry (GC-MS), we characterised VOCs present in the dingo scat and compared the composition with those of GSDs. We identified 58 significant VOCs out of a total of 154 VOCs identified in both dingoes and GSDs. Of these, 12 were significantly higher in the scat of dingoes and 46 elevated in the GSD. Of the 12 elevated in the dingo, three were unique and present in high concentration (>10 ng/g), four were elevated and present in high concentration and five were present at low concentrations (<10 ng/g). We suggest that the detected differences show potential to be incorporated into dingo management strategies. Integrated pest management is a recommended control method for wild dogs in Australia. This study takes the first step in identifying potential population-specific chemical cues in scat as a step towards supplementing existing strategies with chemical approaches aimed at excluding pure dingoes from agricultural lands. Photograph by Barry Eggleton. [ABSTRACT FROM AUTHOR]

Dogs were the first animal to become domesticated by humans, and they represent a classic model system for unraveling the processes of domestication. We compare Australian dingo eye contact and socialization with Basenji and German Shepherd dog (GSD) breeds. Australian dingoes arrived in Australia 5,000–8,000 BP, and there is debate whether they were domesticated before their arrival. The Basenji represents a primitive breed that diverged from the remaining breeds early in the domestication process, while GSDs are a breed dog selected from existing domestic dogs in the late 1800s. We conducted a 4-phase study with unfamiliar and familiar investigators either sitting passively or actively calling each canid. We found 75% of dingoes made eye contact in each phase. In contrast, 86% of Basenjis and 96% of GSDs made eye contact. Dingoes also exhibited shorter eye-gaze duration than breed dogs and did not respond to their name being called actively. Sociability, quantified as a canid coming within 1 m of the experimenter, was lowest for dingoes and highest for GSDs. For sociability duration, dingoes spent less time within 1 m of the experimenter than either breed dog. When compared with previous studies, these data show that the dingo is behaviorally intermediate between wild wolves and Basenji dogs and suggest that it was not domesticated before it arrived in Australia. However, it remains possible that the accumulation of mutations since colonization has obscured historical behaviors, and dingoes now exist in a feralized retamed cycle. Additional morphological and genetic data are required to resolve this conundrum. [ABSTRACT FROM AUTHOR]

Drosophila simulans is hypothesized to have originated in continental East Africa or Madagascar. In this study, we investigated evolutionary forces operating on mitochondrial DNA (mtDNA) in populations of D. simulans from Zimbabwe, Malawi, Tanzania, and Kenya. Variation in mtDNA may be affected by positive selection, background selection, demographic history, and/or any maternally inherited factor such as the bacterial symbiont Wolbachia. In East Africa, the wRi and wMa Wolbachia strains associate with the siII or siIII mitochondrial haplogroups, respectively. To ask how polymorphism relates to Wolbachia infection status, we sequenced 1776 bp of mitochondrial DNA and 1029 bp of the X-linked per locus from 79 lines. The two southern populations were infected with wRi and exhibited significantly reduced mtDNA variation, while Wolbachia-uninfected sill flies from Tanzania and Kenya showed high levels of mtDNA polymorphism. These are the first known populations of D. simulans that do not exhibit reduced mtDNA variation. We observed no mitochondrial variation in the siIII haplogroup regardless of Wolbachia infection status, suggesting positive or background selection. These populations offer a unique opportunity to monitor evolutionary dynamics in ancestral populations that harbor multiple strains of Wolbachia.

Research has been conducted on Drosophila simulans mitochondrial DNA population subdivision. Results suggest that mitochondrial DNA is not a good indicator of D. simulans organismal subdivision.

INTRODUCTION This paper is a guide to all the cone-bearing plants (conifers) of the northeast Alabama. Plant species occurring in adjacent highland counties are also part of this flora. The [...]

INTRODUCTION The following families are in the order Polypodiales treated in this paper are Dryopteridaceae (wood fern family), Hymenophyllaceae (filmy fern family), Lygodiaceae (climbing fern family), Marsileaceae (water-clover family), and [...]

INTRODUCTION This paper concludes the study of pteridophytes of Northeast Alabama and adjacent highlands. The final families treated are Polypodiaceae (polypody family), Pteridaceae (maidenhair fern family), Thelypteridaceae (marsh fern family), [...]

Research has been conducted on the Wolbachia pipientis strains in Drosophila simulans. The expression of the cytoplasmic incompatibility and the distribution and population frequencies of these strains have been investigated and the results are reported.

Student-centered approaches are critical to improving outcomes in STEM courses. Collaborative learning, in particular, allows students to co-construct understanding of concepts and refine their skills in analyzing and applying information. For collaborative learning to be effective, groups must engage in productive dialogue. The work reported here characterizes the quality of dialogue during group quizzes in a first-semester organic chemistry course. The group quiz sessions were video and audio recorded. The recordings were transcribed and coded using the Interactive, Constructive, Active, Passive (ICAP) framework. The quiz prompts were analyzed using Marzano’s taxonomy. In this study, students within the group demonstrated varying degrees of interactional quality as defined by the ICAP framework. Our data also indicate that the level of constructive and interactive dialogue is highest and most consistent when prompts are at Marzano Level 3 or higher. Marzano Level 3 prompts required students to compare and contrast concepts or extend their understanding of concepts by developing an analogy. Any benefit derived from collaborative learning depends on the quality of dialogue during the group discussion. Implications of these results for research and teaching are offered.