Eating Disorders: A Reevaluation of the Morphology, Paleoecology, and Phylogenetic Relationships of the Enigmatic Walrus Pelagiarctos.

A reevaluation of the morphology, paleoecology, and phylogenetic relationships of the enigmatic walrus pelagiarctos.

Filed under: Eating Disorders

PLoS One. 2013; 8(1): e54311
Boessenecker RW, Churchill M

A number of aberrant walruses (Odobenidae) have been described from the Neogene of the North Pacific, including specialized suction-feeding and generalist fish-eating taxa. At least one of these fossil walruses has been hypothesized to have been a specialized predator of other marine mammals, the middle Miocene walrus Pelagiarctos thomasi from the Sharktooth Hill Bonebed of California (16.1-14.5 Ma).A new specimen of Pelagiarctos from the middle Miocene “Topanga” Formation of southern California (17.5-15 Ma) allows a reassessment of the morphology and feeding ecology of this extinct walrus. The mandibles of this new specimen are robust with large canines, bulbous premolars with prominent paraconid, metaconid, hypoconid cusps, crenulated lingual cingula with small talonid basins, M(2) present, double-rooted P(3)-M(1), single-rooted P(1) and M(2), and a P(2) with a bilobate root. Because this specimen lacks a fused mandibular symphysis like Pelagiarctos thomasi, it is instead referred to Pelagiarctos sp. This specimen is more informative than the fragmentary holotype of Pelagiarctos thomasi, permitting Pelagiarctos to be included within a phylogenetic analysis for the first time. Analysis of a matrix composed of 90 cranial, dental, mandibular and postcranial characters indicates that Pelagiarctos is an early diverging walrus and sister to the late Miocene walrus Imagotaria downsi. We reevaluate the evidence for a macropredatory lifestyle for Pelagiarctos, and we find no evidence of specialization towards a macrophagous diet, suggesting that Pelagiarctos was a generalist feeder with the ability to feed on large prey.This new specimen of Pelagiarctos adds to the knowledge of this problematic taxon. The phylogenetic analysis conclusively demonstrates that Pelagiarctos is an early diverging walrus. Pelagiarctos does not show morphological specializations associated with macrophagy, and was likely a generalist predator, feeding on fish, invertebrates, and the occasional warm-blooded prey item.
HubMed – eating


Role of vaspin in human eating behaviour.

Filed under: Eating Disorders

PLoS One. 2013; 8(1): e54140
Breitfeld J, Tönjes A, Gast MT, Schleinitz D, Blüher M, Stumvoll M, Kovacs P, Böttcher Y

The adipokine vaspin (visceral adipose tissue derived serine protease inhibitor, serpinA12) follows a meal-related diurnal variation in humans and intracerebroventricular vaspin administration leads to acutely reduced food intake in db/db mice. We therefore hypothesized that vaspin may play a role in human eating behaviour.We measured serum vaspin concentrations in 548 subjects from a self-contained population of Sorbs (Germany) who underwent detailed metabolic testing including eating behaviour assessments using the three-factor eating questionnaire. In addition, genetic variation within vaspin was assessed by genotyping 28 single nucleotide polymorphisms (SNPs) in all study subjects.Serum vaspin concentrations correlated positively with restraint, disinhibition and hunger (all P<0.05), although the correlations did not withstand further adjustments for age, gender and BMI (all P>0.05). Independent of observed correlations, genetic variants in vaspin were associated with serum vaspin levels but showed no significant association with any of the eating behaviour phenotypes after accounting for multiple testing (P?0.05 after adjusting for age, gender and BMI).Our data suggest that serum vaspin concentrations might modulate human eating behaviour, which does not seem to be affected by common genetic variation in vaspin.
HubMed – eating


Probiotic bacteria induce a ‘glow of health’.

Filed under: Eating Disorders

PLoS One. 2013; 8(1): e53867
Levkovich T, Poutahidis T, Smillie C, Varian BJ, Ibrahim YM, Lakritz JR, Alm EJ, Erdman SE

Radiant skin and hair are universally recognized as indications of good health. However, this ‘glow of health’ display remains poorly understood. We found that feeding of probiotic bacteria to aged mice induced integumentary changes mimicking peak health and reproductive fitness characteristic of much younger animals. Eating probiotic yogurt triggered epithelial follicular anagen-phase shift with sebocytogenesis resulting in thick lustrous fur due to a bacteria-triggered interleukin-10-dependent mechanism. Aged male animals eating probiotics exhibited increased subcuticular folliculogenesis, when compared with matched controls, yielding luxuriant fur only in probiotic-fed subjects. Female animals displayed probiotic-induced hyperacidity coinciding with shinier hair, a feature that also aligns with fertility in human females. Together these data provide insights into mammalian evolution and novel strategies for integumentary health.
HubMed – eating


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