Lunar Rover Model - Reengineering of an Existing Mobile Platform towards the realization of a Rover Autonomy Testbed

The Automation & Robotics Section of the European Space Agency (ESA) is developing a platform for investigation of different levels of autonomy of planetary rovers. Within this scope a physical flight model is required and the Lunar Rover Model (LRM) is chosen. The LRM is a 4 wheel, medium-scale (120kg) Moon exploration rover breadboard, equipped with a 5- DOF robotic arm. This paper presents the complete refurbishment and motion control redesign. Therefore the rover is equipped with a new distributed motion control architecture based on CANopen. Following the hardware upgrades, a complete dynamic model of the rover is developed in 20sim and algorithms for all the rover locomotion modes are analyzed and implemented. Subsequently all the locomotion control algorithms are ported on the rover and the control performance is evaluated using high accuracy measurement systems

Sometimes Sperm Whales (Physeter macrocephalus) Cannot Find Their Way Back to the High Seas: A Multidisciplinary Study on a Mass Stranding

BACKGROUND: Mass strandings of sperm whales (Physeter macrocephalus) remain peculiar and rather unexplained events, which rarely occur in the Mediterranean Sea. Solar cycles and related changes in the geomagnetic field, variations in water temperature and weather conditions, coast geographical features and human activities have been proposed as possible causes. In December 2009, a pod of seven male sperm whales stranded along the Adriatic coast of Southern Italy. This is the sixth instance from 1555 in this basin. METHODOLOGY/PRINCIPAL FINDINGS: Complete necropsies were performed on three whales whose bodies were in good condition, carrying out on sampled tissues histopathology, virology, bacteriology, parasitology, and screening of veins looking for gas emboli. Furthermore, samples for age determination, genetic studies, gastric content evaluation, stable isotopes and toxicology were taken from all the seven specimens. The animals were part of the same group and determined by genetic and photo-identification to be part of the Mediterranean population. Causes of death did not include biological agents, or the "gas and fat embolic syndrome", associated with direct sonar exposure. Environmental pollutant tissue concentrations were relatively high, in particular organochlorinated xenobiotics. Gastric content and morphologic tissue examinations showed a prolonged starvation, which likely caused, at its turn, the mobilization of lipophilic contaminants from the adipose tissue. Chemical compounds subsequently entered the blood circulation and may have impaired immune and nervous functions. CONCLUSIONS/SIGNIFICANCE: A multi-factorial cause underlying this sperm whales' mass stranding is proposed herein based upon the results of postmortem investigations as well as of the detailed analyses of the geographical and historical background. The seven sperm whales took the same "wrong way" into the Adriatic Sea, a potentially dangerous trap for Mediterranean sperm whales. Seismic surveys should be also regarded as potential co-factors, even if no evidence of direct impact has been detected

Biogeography in the deep : hierarchical population genomic structure of two beaked whale species

Funding for this research was provided by the Office of Naval Research, Award numbers N000141613017 and N000142112712. ABO was supported by a partial studentship from the University of St Andrews, School of Biology; OEG by the Marine Alliance for Science and Technology for Scotland (Scottish Funding Council grant HR09011); ELC by a Rutherford Discovery Fellowship from the Royal Society of New Zealand Te Aparangi; NAS by a Ramon y Cajal Fellowship from the Spanish Ministry of Innovation; MLM by the European Union’s Horizon 2020 Research and Innovation Programme (Marie Skłodowska-Curie grant 801199); CR by the Marine Institute (Cetaceans on the Frontier) and the Irish Research Council; and MTO by the Hartmann Foundation.The deep sea is the largest ecosystem on Earth, yet little is known about the processes driving patterns of genetic diversity in its inhabitants. Here, we investigated the macro- and microevolutionary processes shaping genomic population structure and diversity in two poorly understood, globally distributed, deep-sea predators: Cuvier’s beaked whale (Ziphius cavirostris) and Blainville’s beaked whale (Mesoplodon densirostris). We used double-digest restriction associated DNA (ddRAD) and whole mitochondrial genome (mitogenome) sequencing to characterise genetic patterns using phylogenetic trees, cluster analysis, isolation-by-distance, genetic diversity and differentiation statistics. Single nucleotide polymorphisms (SNPs; Blainville’s n = 43 samples, SNPs=13988; Cuvier’s n = 123, SNPs= 30479) and mitogenomes (Blainville’s n = 27; Cuvier’s n = 35) revealed substantial hierarchical structure at a global scale. Both species display significant genetic structure between the Atlantic, Indo-Pacific and in Cuvier’s, the Mediterranean Sea. Within major ocean basins, clear differentiation is found between genetic clusters on the east and west sides of the North Atlantic, and some distinct patterns of structure in the Indo-Pacific and Southern Hemisphere. We infer that macroevolutionary processes shaping patterns of genetic diversity include biogeographical barriers, highlighting the importance of such barriers even to highly mobile, deep-diving taxa. The barriers likely differ between the species due to their thermal tolerances and evolutionary histories. On a microevolutionary scale, it seems likely that the balance between resident populations displaying site fidelity, and transient individuals facilitating gene flow, shapes patterns of connectivity and genetic drift in beaked whales. Based on these results, we propose management units to facilitate improved conservation measures for these elusive species.Publisher PDFPeer reviewe

Drivers of population structure of the bottlenose dolphin (Tursiops truncatus) in the Eastern Mediterranean Sea

The drivers of population differentiation in oceanic high dispersal organisms, have been crucial for research in evolutionary biology. Adaptation to different environments is commonly invoked as a driver of differentiation in the oceans, in alternative to geographic isolation. In this study, we investigate the population structure and phylogeography of the bottlenose dolphin (Tursiops truncatus) in the Mediterranean Sea, using microsatellite loci and the entire mtDNA control region. By further comparing the Mediterranean populations with the well described Atlantic populations, we addressed the following hypotheses: (1) bottlenose dolphins show population structure within the environmentally complex Eastern Mediterranean Sea; (2) population structure was gained locally or otherwise results from chance distribution of preexisting genetic structure; (3) strong demographic variations within the Mediterranean basin have affected genetic variation sufficiently to bias detected patterns of population structure. Our results suggest that bottlenose dolphin exhibits population structures that correspond well to the main Mediterranean oceanographic basins. Furthermore, we found evidence for fine scale population division within the Adriatic and the Levantine seas. We further describe for the first time, a distinction between populations inhabiting pelagic and coastal regions within the Mediterranean. Phylogeographic analysis suggests that current genetic structure, results mostly from stochastic distribution of Atlantic genetic variation, during a recent postglacial expansion. Comparison with Atlantic mtDNA haplotypes, further suggest the existence of a metapopulation across North Atlantic/Mediterranean, with pelagic regions acting as source for coastal environments

Mediterranean sperm whales, <i>Physeter macrocephalus</i>:the precarious state of a lost tribe

First observed in the classical era, a population of sperm whales (Physeter macrocephalus) persists to this day in the deep waters of the Mediterranean Sea. Genetic and observational evidence support the notion that this is an isolated population, separated from its Atlantic neighbours. These whales depend on mesopelagic squid for food, and appear to occupy a very similar ecological niche to sperm whales in the open oceans. Recent evidence proving that individuals can pass between the eastern and western deep water basins confirms that this is a single population, not isolated into western and eastern stocks. We lack robust information on their population status, but they could number in the hundreds rather than thousands, and current densities appear to be much lower than those reported in the 1950s, suggesting that we should be very concerned about the conservation status of this population. This makes it vitally important to address the serious threats posed by ship strikes and entanglement in fishing nets, especially driftnets, and to carefully monitor other potential sources of anthropogenic impact. A step change in funding to collect better data and a clear shift in policy priorities are needed if we are to be serious about conserving this population

Could European marine conservation policy benefit from systematic conservation planning?

1. The Natura 2000 network of protected areas aims to assure the long-term survival of Europe’s most valuable and threatened species and habitats. Yet, evidence shows that the present network fails to represent effectively the biodiversity of the region. 2. Priority areas for conservation of coastal and offshore biodiversity features in the Greek Ionian Sea were identified, based on the principles of systematic conservation planning (SCP). SCP is a transparent method for the design ofMPA networks and is considered more efficient and successful in representing the biodiversity of a region. 3. The prioritization software Marxan was used and three scenarios with different sets of targets for 17 (high and low priority) conservation features were produced. These scenarios explicitly took into account socio-economic factors expressed as a single cost metric, weighting different economic sectors in proportion to their contribution to the GDP of the region. Then results were compared with the existing Natura 2000 sites in terms of goal achievement, area requirements, and cost. 4. The solutions produced by the systematic approach demanded less area and lower cost to achieve the goals set, when the selection of all Natura 2000 sites was not forced. Existing Natura 2000 sites alone failed to achieve conservation goals for some EU priority and other important coastal and offshore habitats and species of the Mediterranean Sea. 5. It is suggested that the use of systematic conservation planning and related computational tools could benefit the selection of European marine priority areas, especially in the context of ecosystem-based marine spatial management.JRC.H.1-Water Resource