Measuring the Strength of Human–Animal Bonds in Zoos

Repeated interactions within individual human and animal dyads can lead to the establishment of human–animal relationships (HARs), which may vary in quality from good to bad, defined in terms of the positivity (e.g., friendly contact, play) or negativity (e.g., aggression) of the interactions on which they are based. Particularly good HARs can be regarded as Human– Animal Bonds (HABs) if they are reciprocal and promote wellbeing in both parties. Although there is extensive evidence of the effects of HARs in agricultural animals and HABs in companion animals, there has been less investigation of these relationships in zoos, even though the development of HARs/HABs between zoo animals and their keepers could have important consequences for the welfare of both. Here we apply a modified version of the Lexington Attachment to Pets Scale (LAPS) in a zoo setting to quantify the strength of attachment of a sample of 22 keepers to the animals in their care at the zoo (ZA), in comparison with their attachment to their companion animals at home (PA). Results showed that mean PA scores (47.54 ± 3.6) were significantly higher than mean ZA scores (32.89 ± 2.6; t = –5.16, df = 13, p < 0.001), indicating stronger attachment to the companion animals. PA scores were lower in keepers who thought it inappropriate to have a bond with a zoo animal, compared with those who deemed it appropriate. Thus, HABs do appear to occur in the zoo context, though they are weaker than those developed in the home. This work also shows that a modified LAPS questionnaire is a suitable instrument for further investigation of HABs in zoos.     

HALDANE'S RULE IS EXTENDED TO PLANTS WITH SEX CHROMOSOMES

Haldane's rule is an empirical phenomenon that has been observed in animals with sex chromosomes. The rule states that the heterogametic sex (XY or ZW) will be “absent, rare, or sterile” following hybridization between two species. Despite the near ubiquity of Haldane's rule in animal hybridizations, it has not been documented in organisms other than animals. Here, we show evidence for both rarity and sterility in hybrid male but not female offspring in crosses between three dioecious plant species from the genus Silene with heteromorphic (XY) sex chromosomes. Our results are consistent with Haldane's rule, extending its applicability to plants with sex chromosomes.     

Is body size a good indicator of fecundity in the genus Thaumetopoea? A story told by two intrageneric Mediterranean forest defoliators

1. Body size correlates with several factors such as reproductive fitness, environmental changes, the quality and quantity of food during critical development stages, and the feeding season. For the Palearctic moths of the genus Thaumetopoea (Lepidoptera; Notodontidae), the larval development is crucial and differs between species according to their feeding season; larvae of the pine processionary moth Thaumetopoea pityocampa (Denis & Schiffermüller 1775) feed during winter while larvae of its congeneric cedar processionary moth Thaumetopoea bonjeani (Powell 1922) develop during summer in North Africa.
2. This discrepancy in lifecycles leads to different reproductive traits such as egg batch length, number of eggs per batch, eggs protection mechanisms and female body size.
3. According to Darwin's fecundity advantage hypothesis (1871), female body size should have a positive influence on reproductive fitness, since larger females supposedly have higher fecundity. The universal allometric scaling phenomenon rule proposed by Rensch (1950) predicts that the degree of sexual size dimorphism tends to decrease with the increase of female body size.
4. Here, two morphometrical parameters that is, body size and scale size, estimated from body measurements of individuals of both species, feeding on the same host Atlantic cedar Cedrus atlantica (Manetti & Carrière 1855) (Pinales; Pinaceae) in Algeria were proposed. The aim was to find out traits that might rule the competition for food and space, in particularly fecundity and body size.
5. Results of the present study highlight a female-biased sexual size dimorphism in both species. The positive correlation between female body size and fecundity shown in this study weakly supports Darwin's hypothesis. Finally, the intrageneric test performed leads to conclude that Rensch's rule does not hold in the considered species.

     

Deletion of Mbtps1 (Pcsk8, S1p,Ski-1) Gene in Osteocytes Stimulates Soleus Muscle Regeneration and Increased Size and Contractile Force with Age

Conditional deletion of Mbtps1 (cKO) protease in bone osteocytes leads to an age-related increase in mass (12%) and in contractile force (30%) in adult slow twitch soleus muscles (SOL) with no effect on fast twitch extensor digitorum longus muscles. Surprisingly, bone from 10–12-month-old cKO animals was indistinguishable from controls in size, density, and morphology except for a 25% increase in stiffness. cKO SOL exhibited increased expression of Pax7, Myog, Myod1, Notch, and Myh3 and 6-fold more centralized nuclei, characteristics of postnatal regenerating muscle, but only in type I myosin heavy chain-expressing cells. Increased expression of gene pathways mediating EGF receptor signaling, circadian exercise, striated muscle contraction, and lipid and carbohydrate oxidative metabolism were also observed in cKO SOL. This muscle phenotype was not observed in 3-month-old mice. Although Mbtps1 mRNA and protein expression was reduced in cKO bone osteocytes, no differences in Mbtps1 or cre recombinase expression were observed in cKO SOL, explaining this age-related phenotype. Understanding bone-muscle cross-talk may provide a fresh and novel approach to prevention and treatment of age-related muscle loss.     

Handstand Scent Marking in the Dwarf Mongoose (Helogale parvula)

Many mammal species adopt marking postures that elevate their scent deposits. The most extreme of these is handstand marking, in which an individual reverses against an upright object, flings its hind legs into the air above its back and balances bipedally on its fore feet. The resulting anogenital deposit is thus raised one full body length above ground level. It has been suggested that this energetically costly form of marking serves to provide conspecifics with information about the marker's body size and hence competitive ability. However, this explanation assumes that the height of an individuals’ deposit does reflect accurately its body size, an assumption that has never been tested in any hand‐standing species. This study investigated the relationship between body size and handstand mark height in a wild population of dwarf mongooses (Helogale parvula) in South Africa. We found that although body size and marking height were correlated positively for female dwarf mongooses, they were not related for males. Male dwarf mongooses (who are subject to intrasexual competition from outside their group) invested more heavily in anogenital range marking, marking at three times the female frequency and placing their deposits significantly higher than females (although they were not dimorphic). Males that were particularly vulnerable to rivals (i.e. those that were small for their age) tended to mark higher than more robust age‐mates, in keeping with the predictions of Adams & Mesterton‐Gibbons’ (1995, J. Theor. Biol.175, 405–421). model of deceptive threat communication. These findings suggest strongly that the height of anogenital scent deposits is of social significance to dwarf mongooses.     

Genetic variation in supernatant malate dehydrogenase of birds and reptiles

Electrophoretic variants of supernatant malate dehydrogenase were found within populations of a brid (Pitohui kirhocephalus) and of a reptile (Chrysemys picta). Upon starch gel electrophoresis, tissue extracts from variant individuals exhibit three equally spaced bands of supernatant malate dehydrogenase activity, whose staining intensities are approximately in a ratio of 1:2:1. Normal individuals, on the other hand, exhibit a single major band which is identical in mobility with the fastest of the variant bands. Immunological tests show that the Pitohui and Chrysemys enzymes are homologous with the well-characterized supernatant malate dehydrogenase of the domestic chicken. These results along with those obtained on other species imply that birds, reptiles, mammals, and certain invertebrates may possess a single locus coding for supernatant malate dehydrogenase. By contrast, some species of fishes and invertebrates possess multiple loci for this enzyme. A notable feature of the present investigation was the use of phenoxyethanol for extracting malate dehydrogenases from bird tissues. Extracts were prepared simply by soaking tissue in an aqueous solution of this reagent, no homogenization or centrifugation being required.This investigation was supported by funds from a research grant awarded by the National Science Foundation (GB-13119) and a U.S. Public Health Service Training Grant (GM 31-12).     

Nutrients affect allocation to male and female function in Abutilon theophrasti (Malvaceae)

In a pair of similar experiments, we examined the effects of varying substrate nutrient levels on several measures of male and female function in Abutilon theophrasti (Malvaceae). In the first trial, plants adjusted allocation to female function at several levels: number of flowers initiated, locule number, percentage of fruits matured, and percentage of ovules matured. In the second trial, plants were much larger, opened more flowers, and matured more fruit (in total but not on a percentage basis). However, in response to nutrient level, plants adjusted maternal investment at fewer levels than in the first trial. Seed mass varied between, but not within, trials. Little to no adjustment was seen in male characters within either trial, although flower number differed within trials and stamen number differed between trials. The lack of adjustment of paternal investment may be due to the fact that A. theophrasti is primarily an autogamous species. Between the two trials, growing conditions, primarily light intensity, varied and plants adjusted their allocation to reproduction differently, indicating plasticity in this trait.