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The origin of the German cockroach, Blattella germanica, is enigmatic, in part because it is ubiquitous worldwide in human-built structures but absent from any natural habitats. The first historical records of this species are from ca. 250 years ago (ya) from central Europe (hence its name). However, recent research suggests that the center of diversity of the genus is Asian, where its closest relatives are found. To solve this paradox, we sampled genome-wide markers of 281 cockroaches from 17 countries across six continents. We confirm that B. germanica evolved from the Asian cockroach Blattella asahinai approximately 2,100 ya, probably by adapting to human settlements in India or Myanmar. Our genomic analyses reconstructed two primary global spread routes, one older, westward route to the Middle East coinciding with various Islamic dynasties (~1,200 ya), and another younger eastward route coinciding with the European colonial period (~390 ya). While Europe was not central to the early domestication and spread of the German cockroach, European advances in long-distance transportation and temperature-controlled housing were likely important for the more recent global spread, increasing chances of successful dispersal to and establishment in new regions. The global genetic structure of German cockroaches further supports our model, as it generally aligns with geopolitical boundaries, suggesting regional bridgehead populations established following the advent of international commerce. [ABSTRACT FROM AUTHOR]

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Current methods for identifying resource preferences in dung beetles are based on above‐ground trials. Although useful, these methods do not directly investigate resource provisioning of offspring below ground, missing an important part of dung beetle ecology.We tested the potential for UV‐fluorescent and non‐fluorescent coloured glitters to be used as markers for tracing the origin of dung incorporated into brood balls (dung shaped by parental beetles enclosing an egg), and so aid in a more complete understanding of resource use in dung beetles. We tested the effect of glitter addition on brood ball production in two species of tunnelling dung beetles, Onthophagus taurus and Euoniticellus fulvus.There was no effect of glitter addition on brood ball production during no‐choice tests for each species: both species made a similar number of brood balls, regardless of glitter presence or glitter colour. In a separate choice trial, O. taurus showed no preference for dung when presented with four dung pats containing four unique glitter colours.Here we show that glitter can be used as an effective marker of individual brood ball origin in tunnelling dung beetles. This method provides a useful tool for tracking below ground resource use and larval provisioning experiments in dung beetles. [ABSTRACT FROM AUTHOR]

This dissertation is divided into three freestanding chapters. Chapter I describes the total synthesis of the cytotoxic marine natural product trans-2,5-bis(6'-bromo-3'­ indolyl)piperazine (1), as well as racemic cis-2,5-bis(6'-bromo-3'-indolyl)piperazine (78). Also described are the syntheses of two additional analogs of the natural product 1; trans-2,5-bis(5'-bromo-3'-indolyl)piperazine (79) and racemic cis-2,5-bis(5'-bromo-3'­ indolyl)piperazine (80). These piperazines were prepared by electophillic addition of the indole to cis-3,6-dibromo-1 ,4-bis(tert-butoxycarbonyl)-2,5-piperazinedione, followed by isomerization and reduction of the resulting 3,6-bis(indolyl)-2,5-piperazinediones with borane-tetrahydrofuran. The piperazine products 1 and 78-80 were all found to be cytotoxic. In collaboration with the National Cancer Institute (NCI), in vivo testing was performed. The piperazine compounds 78, 80 and 1 have been identified as selectively cytotoxic to colon tumors. NCI has detetmined that the maximally tolerated doses in mice of 1 and 78 are 400 and 450 mg/kg, respectively. Efforts are underway to provide more of 1, 78 and 80 for further in vivo testing by the NCI. In addition the piperazine products were found to inhibit phorbol-induced inflammation in the Mouse Ear Edema Assay at levels ranging from 44% for 78, 69% for 80 and 71% for 1 to a maximum of 80% for 79.Chapter 2 describes the isolation and stucture elucidation of the marine natural product (2R, 3R, 10R)-(Z)-2-amino-1,3,10-trihydroxy-11-octadecene (81). The stucture was determined by a combination of spectral analyses and derivatizations. The Modified Mosher Method was used to determine the absolute configurations of C-3 and C-l 0. The compound was determined to possess broad spectrum anti-microbial properties, and was also found to inhibit phorbol-induced inflammation in the Mouse Ear Edema Assay at a level of 43%.Chapter 3 describes the isolation and synthesis of a glycine derivative of the cytotoxic marine natural product ilimaquinone. The structure of the new compound, called glycinylilimaquinone (91) was determined by spectral methods and by partial synthesis. Compound 91 was also found to be cytotoxic (eg. HCT-116, IC50 = 7.8)µg/mL) and evaluated against the P388 murine lukemia model in vivo, but at a maximally tolerated dose showed no anti-tumor activity. Also described are stucture-activity relationships for some ilimaquinone analogs tested for Golgi vessiculation and microtubule depolymerization in rat kidney cells.

Prospective memory (PM) involves forming intentions, retaining those intentions, and later executing those intended responses at the appropriate time. Few studies have investigated this capacity in animals. Monkeys performed a computerized task that assessed their ability to remember to make a particular response if they observed a PM cue embedded within an ongoing learning-set (LS) task. At a break in the LS task, monkeys selected one of two icons indicating that they had or had not encoded the occurrence of the PM cue (the latter icon resumed the LS task). Critically, during this response period, the PM response icon appeared after a delay during which monkeys could self-initiate the PM response prior to receiving any external prompt. Monkeys selected the PM and LS icons when each was the optimal response, illustrating that they could encode, store, and respond appropriately to a stimulus event in the future. Critically, some monkeys self-initiated the PM response prior to that icon's appearance, indicating that they could retrieve the PM and act on their intention to make that response without the aid of a prompt. These monkeys appeared capable of using PM in this task. Thus, this capacity appears not to be limited to humans. (Contains 2 tables and 3 figures.)

In three experiments, four chimpanzees made choices between two visible food options to assess the validity of the "selective value effect" (the assignment of value to only the most preferred type of food presented in a comparison). In Experiment 1, we established that all chimpanzees preferred single banana pieces to single apple pieces before presenting the critical test. In this test two chimpanzees preferred a mix of one banana piece and one apple piece to a single banana piece when both banana pieces were approximately the same size, but two chimpanzees were indifferent between the two options, exhibiting the selective value effect. In Experiment 2, when the banana pieces in both options were more closely equated in size, the chimpanzees were biased to choose the single banana piece over the mixed array even though this was the smaller total amount of food. However, in Experiment 3, when we introduced longer intervals between each trial, the chimpanzees preferred the mixed set and thus the larger total amount of food. The results demonstrate that only some chimpanzees exhibit the choice pattern indicative of the selective value effect, and they do so only when item size is not carefully controlled and trials are presented quickly in succession. Thus, the behavior pattern originally labeled the selective value effect may actually be explained by a combination of chimpanzees' sensitivity to small differences in preferred food amount and chimpanzees tendency to avoid less preferred foods that would delay the acquisition of further preferred food items. (Contains 3 figures and 1 table.)

Learning styles in capuchin monkeys were assessed with a computerized reversal-learning task called the mediational paradigm. First, monkeys were trained to respond with 90% accuracy on a two-choice discrimination (A+B-). Then the authors examined differences in performance on three different types of reversal trials (A-B+, A-C+, B+C-), each of which offered differing predictions for performance, depending on whether the monkeys were using associative cues or rule-based strategies. Performance indicated that the monkeys mainly learned to avoid the B stimulus during training, as the A-C+ condition produced the best performance levels. Therefore, negative stimuli showed greater control over responding after reversal and reflected a more associative rather than rule-based form of learning. (Contains 1 table and 1 figure.)