Applicability of Single-Camera Photogrammetry to Determine Body Dimensions of Pinnipeds: Galapagos Sea Lions as an Example

Meise K, Mueller B, Zein B, Trillmich F. Applicability of Single-Camera Photogrammetry to Determine Body Dimensions of Pinnipeds: Galapagos Sea Lions as an Example. PLoS ONE. 2014;9(7): e101197.Morphological features correlate with many life history traits and are therefore of high interest to behavioral and evolutionary biologists. Photogrammetry provides a useful tool to collect morphological data from species for which measurements are otherwise difficult to obtain. This method reduces disturbance and avoids capture stress. Using the Galapagos sea lion (Zalophus wollebaeki) as a model system, we tested the applicability of single-camera photogrammetry in combination with laser distance measurement to estimate morphological traits which may vary with an animal’s body position. We assessed whether linear morphological traits estimated by photogrammetry can be used to estimate body length and mass. We show that accurate estimates of body length (males: ±2.0%, females: ±2.6%) and reliable estimates of body mass are possible (males: ±6.8%, females: 14.5%). Furthermore, we developed correction factors that allow the use of animal photos that diverge somewhat from a flat-out position. The product of estimated body length and girth produced sufficiently reliable estimates of mass to categorize individuals into 10 kg-classes of body mass. Data of individuals repeatedly photographed within one season suggested relatively low measurement errors (body length: 2.9%, body mass: 8.1%). In order to develop accurate sex- and age-specific correction factors, a sufficient number of individuals from both sexes and from all desired age classes have to be captured for baseline measurements. Given proper validation, this method provides an excellent opportunity to collect morphological data for large numbers of individuals with minimal disturbance

Longitudinal dynamics of skin bacterial communities in the context of Staphylococcus aureus decolonization

Decolonization with topical antimicrobials is frequently prescribed in health care and community settings to prevent Staphylococcus aureus infection. However, effects on commensal skin microbial communities remains largely unexplored. Within a household affected by recurrent methicillin-resistant S. aureus skin and soft tissue infections (SSTI), skin swabs were collected from the anterior nares, axillae, and inguinal folds of 14 participants at 1- to 3-month intervals over 24 months. Four household members experienced SSTI during the first 12-months (observational period) and were prescribed a 5-day decolonization regimen with intranasal mupirocin and bleach water baths at the 12-month study visit. We sequenced the 16S rRNA gene V1-V2 region and compared bacterial community characteristics between the pre- and post-intervention periods and between younger and older subjects. The median Shannon diversity index was stable during the 12-month observational period at all three body sites. Bacterial community characteristics (diversity, stability, and taxonomic composition) varied with age. Among all household members, not exclusively among the four performing decolonization, diversity was unstable throughout the year post-intervention. In the month after decolonization, bacterial communities were changed. Although communities largely returned to their baseline states, relative abundance of some taxa remained changed throughout the year following decolonization (e.g., more abundan

Sharing Is Caring -Is This True Or What Else Explains the Tremendous Growth of the Sharing Economy?

Although the 'sharing economy' is growing at an enormous pace, research regarding the individual needs that drive this trend is still scarce. Therefore, our study aims at a comprehensive identification of the different needs pursued with sharing. We identify sixteen needs and, moreover, demonstrate differences between different sharing platforms

Authenticity in branding – exploring antecedents and consequences of brand authenticity

Purpose Consumer demand for authentic brands is steadily rising. With increased pressure to accommodate this demand, researchers and marketers seek to understand how to influence a brand’s perceived authenticity. The purpose of this paper is to build a link between previous research on authenticity and thus gain a deeper understanding of the influencing factors of brand authenticity and its consumer outcomes. Design/methodology/approach Building on an extensive literature review, the authors identify various antecedents of brand authenticity that are closely connected with the brand’s past, its virtuousness, consumers’ self-identification with the brand perceiver’s own self and individuals representing the brand, as well as relational outcomes as consequences of a brand’s perceived authenticity. As brand authenticity is a subjective construct, the authors include brand involvement to test for moderator effects. For data collection, they conduct an online survey that generates 509 datasets. To test the hypotheses, the authors use structural equation modeling. Findings The results demonstrate that brand authenticity can be influenced by the identified variables (i.e. brand heritage, brand nostalgia, brand commercialization, brand clarity, brand’s social commitment, brand legitimacy, actual self-congruence and employee’s passion). Moreover, brand authenticity positively affects brand relationship quality, which in turn positively influences consumers’ behavioral intentions. The analyzed relationships do not vary due to consumer-specific characteristics (i.e. brand involvement). Originality/value In sum, the results regarding the antecedents of brand authenticity demonstrate that a company can influence brand authenticity through different approaches, and that it is therefore important to analyze which of the identified antecedents brand management should manipulate to positively impact the perception of the brand’s authenticity. In addition, the findings confirm the positive consequences on consumer behavior ascribed to the authenticity concept by marketing literature

Being on time: size-dependent attendance patterns affect male reproductive success

Meise K, Piedrahita P, Krüger O, Trillmich F. Being on time: size-dependent attendance patterns affect male reproductive success. Animal Behaviour. 2014;93:77-86

Reproductive performance of a tropical apex predator in an unpredictable habitat

Kalberer S, Meise K, Trillmich F, Krüger O. Reproductive performance of a tropical apex predator in an unpredictable habitat. BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY. 2018;72(7): 108.Variation in life history traits is directly linked to individual fitness. This interplay is complicated by environmental perturbations in an unpredictable habitat. To maximise fitness, individuals react to environmental changes by reallocating resources between maintenance, growth and reproduction. Disentangling these factors is complicated as traits are interlinked by trade-offs between current reproduction and future survival and reproduction. This study provides first estimates of life history traits and trade-offs of a tropical apex predator, the Galapagos sea lion (Zalophus wollebaeki), in an unpredictable habitat, the Galapagos archipelago. Thirteen years of individual data on birth mass, early growth and offspring, and environmental data allowed the examination of factors influencing reproductive performance of adult females and calculation of pupping rates. Females became primiparous between ages 4 and 9. Neither oceanographic nor body condition in the females' first year of life influenced age at primiparity. Age at primiparity had no effect on a female's birth rate, on average one pup every 2 years. Sex of a pup did not influence the subsequent inter-birth interval, but first-year pup survival lengthened it. Until age 6, females showed lower birth rate (< 0.40). Fecundity was higher between age 6 and 14 (birth rate 0.40-0.48). We could not detect an influence of inter-annually differing oceanographic conditions on pupping rates. Female Galapagos sea lions appear to deal with variation in early-life history traits and environmental unpredictability by a low but stable reproductive output modified only by the trade-off between current and future reproduction. Life history traits and trade-offs have been examined in many species in temperate regions and in seasonal but predictable tropical habitats. However, they have rarely been investigated in long-lived species in tropical but unpredictable habitats, where the interplay between life history traits, individual fitness and population demography may be more complex. Our long-term dataset for Galapagos sea lion females, a tropical apex predator, shows that the trade-off between current and future reproduction figures prominently in their life history. However, they produce a low, but stable reproductive output largely unaffected by variation in early life history traits and largely independent of environmental unpredictability