When Reintroductions are Augmentations: The Genetic Legacy of Fishers (Martes Pennanti) in Montana

Fishers (Martes pennanti) were purportedly extirpated from Montana by 1930 and extant populations are assumed to be descended from translocated fishers. To determine the lineage of fisher populations, we sequenced 2 regions of the mitochondrial DNA genome from 207 tissue samples from British Columbia, Minnesota, Wisconsin, and Montana. In northwestern Montana, fishers share haplotypes with samples from the upper Midwest and British Columbia; in west-central Montana, we detected haplotypes found in British Columbia samples, but also detected a control region and cytochrome-b haplotype not found in source populations. Based on the unique haplotypes found in west-central Montana, we propose that individuals with these haplotypes are descended from a relic population. Fishers in northwestern Montana are likely descended from fishers from the Midwest and British Columbia

Ecomorphology of Carnivora challenges convergent evolution

Convergent evolution is often reported in the mammalian order Carnivora. Their adaptations to particularly demanding feeding habits such as hypercarnivory and durophagy (consumption of tough food) appear to favour morphological similarities between distantly related species, especially in the skull. However, phylogenetic effect in phenotypic data might obscure such a pattern. We first validated the hypotheses that extant hypercarnivorous and durophagous large carnivorans converge in mandibular shape and form (size and shape). Hypercarnivores generally exhibit smaller volumes of the multidimensional shape and form space than their sister taxa, but this pattern is significantly different from random expectation only when hunting behaviour categorisations are taken into account. Durophages share areas of the morphospace, but this seems to be due to factors of contingency. Carnivorans that hunt in pack exhibit incomplete convergence while even stronger similarities occur in the mandible shape of solitary hunters due to the high functional demands in killing the prey. We identified a stronger phylogenetic signal in mandibular shape than in size. The quantification of evolutionary rates of changes suggests that mandible shape of solitary hunters evolved slowly when compared with other carnivorans. These results consistently indicate that the need for a strong bite force and robust mandible override sheer phylogenetic effect in solitary hunters

Carnivore Translocations and Conservation: Insights from Population Models and Field Data for Fishers (Martes pennanti)

Translocations are frequently used to restore extirpated carnivore populations. Understanding the factors that influence translocation success is important because carnivore translocations can be time consuming, expensive, and controversial. Using population viability software, we modeled reintroductions of the fisher, a candidate for endangered or threatened status in the Pacific states of the US. Our model predicts that the most important factor influencing successful re-establishment of a fisher population is the number of adult females reintroduced (provided some males are also released). Data from 38 translocations of fishers in North America, including 30 reintroductions, 5 augmentations and 3 introductions, show that the number of females released was, indeed, a good predictor of success but that the number of males released, geographic region and proximity of the source population to the release site were also important predictors. The contradiction between model and data regarding males may relate to the assumption in the model that all males are equally good breeders. We hypothesize that many males may need to be released to insure a sufficient number of good breeders are included, probably large males. Seventy-seven percent of reintroductions with known outcomes (success or failure) succeeded; all 5 augmentations succeeded; but none of the 3 introductions succeeded. Reintroductions were instrumental in reestablishing fisher populations within their historical range and expanding the range from its most-contracted state (43% of the historical range) to its current state (68% of the historical range). To increase the likelihood of translocation success, we recommend that managers: 1) release as many fishers as possible, 2) release more females than males (55–60% females) when possible, 3) release as many adults as possible, especially large males, 4) release fishers from a nearby source population, 5) conduct a formal feasibility assessment, and 6) develop a comprehensive implementation plan that includes an active monitoring program

Development of a compliant micro gripper : a thesis submitted in partial fulfillment for the degree of Masters of Engineering in the School of Engineering and Advanced Technology, Massey University

Manipulating micro objects simply and effectively has been a widely discussed and challenging task in recent literature for many reasons. Limitations in complex micro fabrication techniques mean creating extremely small tools at the micro scale is very difficult. Adhesion forces also dominate at this scale, causing anything and everything to stick together. This means that even when these tiny structures are created and introduced to the micro world, they quickly become polluted with contaminants and struggle to pick and place particles without said particle adhering to the tool. Indirect methods for micro manipulation exist, however these can be damaging to biological material such as cells, due to unseen forces being focused into a small point. Having the ability to safely manipulate and separate these objects from a culture is crucial to understanding their individual characteristics. Therefore a safe and reliable method for micro manipulation needs to be developed. This project focuses on investigating the current methods used for micro manipulation in order to identify any possible routes towards developing a simple and yet effective means for manipulating micro objects. A modular micro gripping mechanism is proposed in this report, capable of manipulating many different types of objects such as spherical, non spherical or other arbitrary shapes. The proposed micro gripper combines traditional machining techniques with a complex micro fabrication process to produce a modular mechanism consisting of a sturdy, compliant aluminium base in which replaceable silicon and borosilicate glass end effectors are attached. This creates an easily customisable solution for micro manipulation with an array of different micro tips for different applications. A kinematic analysis for the gripper has been provided which predicts the workspace of the gripper given an input actuation. Design parameters of the gripper have also been optimised through various techniques such as FEA (finite element analysis) simulation and the effects of altering individual flexure beam lengths. The gripper is operated by a piezo actuator with a total capable expansion of 19 mm when 150 VDC is applied. This expansion is then amplified by a factor of 8.1 to a maximum tip displacement of approximately 154 mm. Displacement amplification is achieved by incorporating bridge and lever amplifying techniques into the compliant design. The complete micro gripper is then used to demonstrate manipulation tasks on several different target object types including silica micro beads (spherical and non spherical), a human eyelash and a grain of pollen. These tests are performed to investigate the effect of adhesion forces and also to demonstrate the large size range of capable pick and place objects (6 mm to 500 mm)