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51.
Paul D. McGreevy Dana Georgevsky Johanna Carrasco Michael Valenzuela Deborah L. Duffy James A. Serpell 《PloS one》2013,8(12)
Dogs offer unique opportunities to study correlations between morphology and behavior because skull shapes and body shape are so diverse among breeds. Several studies have shown relationships between canine cephalic index (CI: the ratio of skull width to skull length) and neural architecture. Data on the CI of adult, show-quality dogs (six males and six females) were sourced in Australia along with existing data on the breeds'' height, bodyweight and related to data on 36 behavioral traits of companion dogs (n = 8,301) of various common breeds (n = 49) collected internationally using the Canine Behavioral Assessment and Research Questionnaire (C-BARQ). Stepwise backward elimination regressions revealed that, across the breeds, 33 behavioral traits all but one of which are undesirable in companion animals correlated with either height alone (n = 14), bodyweight alone (n = 5), CI alone (n = 3), bodyweight-and-skull shape combined (n = 2), height-and-skull shape combined (n = 3) or height-and-bodyweight combined (n = 6). For example, breed average height showed strongly significant inverse relationships (p<0.001) with mounting persons or objects, touch sensitivity, urination when left alone, dog-directed fear, separation-related problems, non-social fear, defecation when left alone, owner-directed aggression, begging for food, urine marking and attachment/attention-seeking, while bodyweight showed strongly significant inverse relationships (p<0.001) with excitability and being reported as hyperactive. Apart from trainability, all regression coefficients with height were negative indicating that, across the breeds, behavior becomes more problematic as height decreases. Allogrooming increased strongly (p<0.001) with CI and inversely with height. CI alone showed a strong significant positive relationship with self-grooming (p<0.001) but a negative relationship with chasing (p = 0.020). The current study demonstrates how aspects of CI (and therefore brain shape), bodyweight and height co-vary with behavior. The biological basis for, and significance of, these associations remain to be determined. 相似文献
52.
Human preferences for certain morphological attributes among domestic animals may be entirely individual or, more generally, may reflect evolutionary pressures that favor certain conformation. Artificial selection for attributes, such as short heads and crested necks of horses, may have functional and welfare implications because there is evidence from other species that skull shape co-varies with behaviour. Crested necks can be accentuated by flexion of the neck, a quality that is often manipulated in photographs vendors use when selling horses. Equine head-and-neck positions acquired through rein tension can compromise welfare. Our investigation was designed to identify conformations and postures that people are attracted to when choosing their ‘ideal’ horse. Participants of an internet survey were asked to rate their preference for horse silhouettes that illustrated three gradations of five variables: facial shape, crest height, ear length, ear position and head-and-neck carriage. There were 1,234 usable responses. The results show that overall preferences are for the intermediate, rather than extreme, morphological choices (p=<0.001). They also indicate that males are 2.5 times less likely to prefer thicker necks rather than the intermediate shape, and 4 times more likely to prefer the thinner neck shape. When compared to the novice participants, experienced participants were 1.9 times more likely to prefer a thicker neck shape than the intermediate neck shape and 2.8 times less likely to prefer a thinner neck shape than the intermediate neck shape. There was overall preference of 93% (n=939) for the category of head carriage ‘In front of the vertical’. However, novice participants were 1.8 times more likely to choose ‘behind the vertical’ than ‘in front of the vertical’. Our results suggest that people prefer a natural head carriage, concave facial profile (dished face), larger ears and thicker necks. From these survey data, it seems that some innate preferences may run counter to horse health and welfare. 相似文献
53.
54.
Thomas J. McGreevy Jr Lisa Dabek Marta Gomez-Chiarri Thomas P. Husband 《Zoo biology》2009,28(3):183-196
The Association of Zoos and Aquariums (AZA) Matschie's tree kangaroo (Dendrolagus matschiei) population is at a critical point for assessing long-term viability. This population, established from 19 genetically uncharacterized D. matschiei, has endured a founder effect because only four individuals contributed the majority of offspring. The highly variable mitochondrial DNA (mtDNA) control region was sequenced for five of the female-founders by examining extant representatives of their maternal lineage and compared with wild (n=13) and captive (n=18) D. matschiei from Papua New Guinea (PNG). AZA female-founder D. matschiei control region haplotype diversity was low, compared with captive D. matschiei held in PNG. AZA D. matschiei have only two control region haplotypes because four out of five AZA female-founder D. matschiei had an identical sequence. Both AZA haplotypes were identified among the 17 wild and captive D. matschiei haplotypes from PNG. Genomic DNA extracted from wild D. matschiei fecal samples was a reliable source of mtDNA that could be used for a larger scale study. We recommend a nuclear DNA genetic analysis to more fully characterize AZA D. matschiei genetic diversity and to assist their Species Survival Plan®. An improved understanding of D. matschiei genetics will contribute substantially to the conservation of these unique animals both in captivity and the wild. Zoo Biol 28:183–196, 2009. © 2008 Wiley-Liss, Inc. 相似文献
55.
The classic myotonic dystrophy, Steinert’s disease (DM1) was first described in 1909, and the second type, Ricker’s disease (DM2), in 1994. In 1992 the disease-causing mutation in DM1 was identified as a CTG repeat in the DMPK gene on chromosome 19q, and in 2001 the DM2 mutation was identified as a CCTG repeat expansion in the ZNF9 gene on chromosome 3q. Multisystemic symptoms of the diseases affect skeletal muscle, brain, eye, heart, and the endocrine system. The pathogenesis of both forms seems to be based on a gain-of-function RNA mechanism and on alterations in RNA metabolism and spliceopathy. Our review focuses on clinical features, diagnostic techniques, and new aspects of molecular pathogenesis and therapy. 相似文献
56.
PD Dr. R.C. Betz 《Medizinische Genetik》2009,21(4):505-510
The monogenic inherited isolated alopecias comprise a group of clinically and genetically heterogeneous forms of hairlessness or hair loss. Clinical classification of the isolated alopecias is based on the onset of the disorder, the regions affected, and the structure of the hair shaft. Men and women are equally affected, and the mode of inheritance is autosomal dominant or autosomal recessive. Since the identification of the keratin gene KRT86 as a cause of the so-called monilethrix in 1997, mutations in nine other genes have been identified for various isolated alopecias. These include other keratin genes for monilethrix (KRT81 and KRT83), the hairless gene for atrichia congenita/papular atrichia, the corneodesmosin gene for the autosomal dominant form of hypotrichosis simplex, and the genes desmoglein 4, lipase H, and the G-protein-coupled receptor P2RY5 (LPAR6) for the autosomal recessive forms of hypotrichosis. Molecular genetic and pathophysiological studies of these rare disorders of hair development have contributed significantly to our understanding of the basic mechanisms of hair loss as well as the physiological mechanisms of hair growth. 相似文献
57.
Norian-Rhaetian reefs in Argolis Peninsula,Greece 总被引:2,自引:0,他引:2
PD Dr. Baba Senowbari-Daryan Dr. Dionissios Matarangas Dr. Myrsini Vartis-Matarangas 《Facies》1996,34(1):77-82
Summary Upper Triassic to Lower Jurassic shallow-water carbonate sequences of the ‘Pantokrator limestones’ are widely distributed
in the Argolis Peninsula, southern Greece. Within this sequence are some reef or reefal structures. In the Mavrovouni Mountains,
near Sarmeika, 6 km SE of the ancient theatre of Epidavros (Argolis Peninsula), a Norian-Rhaetian reef complex has been identified.
This is the first well-documented Norian-Rhaetian reef in Greece. The main reef builders are coralline sponges (‘sphinctozoans,’
‘inozoans’, and sclerosponges), followed by dendroid, cerioid, and solitary corals, and algae. The reef type corresponds to
a ‘sponge-coral reef’. 相似文献
58.
Molecular clocks are routinely tested for linearity using a relative rate
test and routinely calibrated against the geological time scale using a
single or average paleontologically determined time of divergence between
living taxa. The relative rate test is a test of parallel rate equality,
not a test of rate constancy. Temporal scaling provides a test of rates,
where scaling coefficients of 1.0 (isochrony) represent stochastic rate
constancy. The fossil record of primates and other mammals is now known in
sufficient detail to provide several independent divergence times for major
taxonomic groups. Molecular difference should scale negatively or
isochronically (scaling coefficients less than 1.0) with divergence time:
where two or more divergence times are available, molecular difference
appears to scale positively (scaling coefficient greater than 1.0). A
minimum of four divergence times are required for adequate statistical
power in testing the linear model: scaling is significantly nonlinear and
positive in six of 11 published investigations meeting this criterion. All
groups studied show some slowdown in rates of molecular change over
Cenozoic time. The break from constant or increasing rates during the
Mesozoic to decreasing rates during the Cenozoic appears to coincide with
extraordinary diversification of placental mammals at the beginning of this
era. High rates of selectively neutral molecular change may be concentrated
in such discrete events of evolutionary diversification.
相似文献
59.
On 15 November 2017 the mouth of the West Kleinemonde Estuary breached following heavy catchment rains and increased river flow. The water level in the estuary following mouth opening decreased by 1.65 m within 24 h, resulting in an almost complete draining of the littoral zone where large beds of the aquatic macrophyte Ruppia cirrhosa and mats of the associated filamentous algae were present. As the water depth within the plant beds decreased, the macrophytes, together with the algal filaments, created an increasingly dense mat, trapping fish that were resident, foraging or passing through the littoral zone. By 16 November 2017 large numbers of fishes belonging to at least 20 species were trapped in pools and depressions within the littoral, as well as within the R. cirrhosa beds and filamentous algal mats in the lower reaches of this system. Other affected taxa included crustaceans, especially isopods, and large numbers of small bivalves attached to macrophyte vegetation. Beneficiaries of the fish kill, in terms of unexpected food availability, included a variety of piscivorous bird species and the Cape clawless otter Aonyx capensis. This is the first documented account of a diverse species fish kill associated with estuary mouth breaching. 相似文献
60.