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San Diego Christian College is a private, evangelical Christian college located in Santee, California, United States, in suburban San Diego. Wikipedia.

Afeworki Y.,University of Groningen | Afeworki Y.,P.A. College | Videler J.J.,University of Groningen | Berhane Y.H.,San Diego Christian College | Bruggemann J.H.,University of Reunion Island
Journal of Fish Biology | Year: 2014

Temporal trends in growth of the rusty parrotfish Scarus ferrugineus were studied on a southern Red Sea fringing reef that experiences seasonal changes in environmental conditions and benthic algal resources. Length increment data from tagging and recapture were compared among periods and sexes and modelled using GROTAG, a von Bertalanffy growth model. The growth pattern of S. ferrugineus was highly seasonal with a maximum occurring between April and June and a minimum between December and March. Body condition followed the seasonal variation in growth, increasing from April to June and decreasing from December to March. The season of maximum growth coincided with high irradiation, temperature increases and peak abundance of the primary food source, the epilithic algal community. There was a decline in growth rate during summer (July to October) associated with a combination of extreme temperatures and lowered food availability. There were strong sexual size dimorphism (SSD) and life-history traits. Terminal-phase (TP) males achieved larger asymptotic lengths than initial-phase individuals (IP) (L∞ 34·55 v. 25·12 cm) with growth coefficients (K) of 0·26 and 0·38. The TPs were growing four times as fast as IPs of similar size. Three individuals changed from IP to TP while at liberty and grew eight times faster than IPs of similar size, suggesting that sex change in S. ferrugineus is accompanied by a surge in growth rate. The SSD in S. ferrugineus thus coincided with fast growth that started during sex change and continued into the TP. Faster growth during sex change suggests that the cost associated with sex change is limited. Journal of Fish Biology © 2014 The Fisheries Society of the British Isles 84 5 May 2014 10.1111/jfb.12372 REGULAR PAPER REGULAR PAPERS © 2014 The Fisheries Society of the British Isles. Source

Marti Mus M.,University of Extremadura | Jeppsson L.,Lund University | Malinky J.M.,San Diego Christian College
Journal of Paleontology | Year: 2014

Hyolithids are a group of Paleozoic lophotrochozoans with a four-pieced skeleton consisting of a conch, an operculum, and a pair of lateral 'spines' named helens. Both the conch and operculum are relatively well known and, to a certain extent, have modern analogues in other lophotrochozoan groups. The helens, on the other hand, are less well known and do not have clear modern analogues. This has hindered the knowledge of the complete morphology of the hyolithid skeleton, as well as other aspects of hyolithid biology, such as the organization of soft parts, and their ability to move. The material studied herein, consisting of disarticulated skeletal elements from the Silurian of Gotland, Sweden, illustrates a complete developmental sequence of a hyolithid species and includes the first complete, three-dimensionally preserved helens. Our material confirms that helens were massive skeletal elements, whose growth started proximally with the deposition of a central, coherent lamella. Further shell accretion took place around this lamella, but followed a particular accretion pattern probably constrained by the presence of marginal muscle attachment sites on the proximal-most portion of the helens. These muscle attachment sites were ideally located to allow a wide range of movements for the helens, suggesting that hyolithids may have been relatively mobile organisms. © 2014 The Paleontological Society. Source

Brashears J.,San Diego Christian College | Aiello A.,Smithsonian Tropical Research Institute | Seymoure B.M.,Smithsonian Tropical Research Institute | Seymoure B.M.,Arizona State University
Journal of Thermal Biology | Year: 2016

Butterflies regulate their internal thoracic temperature in order to optimize performance activities (e.g. flight, foraging). Previous research has shown that butterfly wings, particularly the innermost portions, play a role in thermoregulation. We investigated to see whether a lightly colored wing band would alter the thermal properties of the banded peacock butterfly (. Anartia fatima) with two within subject experiments in a laboratory setting: (1) band color manipulation in which euthanized individuals were heated to thermal equilibrium with the band unaltered and then again with the wing darkened; (2) wing ablation in which individuals already run through experiment 1 were heated to equilibrium two more times; once with the outer portion of the wing including the band removed and then with the entire wing removed. Individuals were spread so that the dorsal surface of the wing was exposed to illumination from a lamp suspended above. Twelve Anartia fatima males were collected in Panama and were run through experiment one. Four individuals were run through experiment two. We found no effect of darkening the band on the internal thoracic equilibrium temperature, but the darkened band did increase the rate of heating. The wing ablation experiment revealed that wing removal lowered the internal thoracic equilibrium temperature but did not affect the heating rate. Therefore we show that butterfly bands may be important in butterfly thermoregulation and we discuss the importance of the wing band on thermoregulatory abilities in Anartia fatima with respect to the butterfly's natural history. We conclude that the wing band may allow butterflies to reduce heat stress induced by their warm environments. © 2016 Elsevier Ltd. Source

Lulka D.,San Diego Christian College
Culture, Agriculture, Food and Environment | Year: 2011

Proposition 2 sought to transform the microstructure of agricultural production within the state of California. This paper examines the political debate surrounding the ballot initiative and its geographical implications. Proponents and opponents of the proposition utilized scientific and ethical principles to define their respective positions, differentiate legitimate voices from illegitimate voices, and designate which segments of the California population should have a role in determining the character of animal agriculture within the state. The generalities and specificities contained within these principles are shown to approximate different perceptions of the ideal scope of democracy. Amid these tailored principles, common sense also emerged during the election as a notion affecting the potential breadth of political inclusion in such decisions. In association with other ideas, the general character of common sense proved consequential for two reasons: it substantiated populism in politics while its embodied foundation fostered connections between humans and animals. Ultimately, however, common sense is shown to be a double-edged sword. While it appears to have played a role in the projected transformation of California agriculture, such change is not as revolutionary as some would suggest for it is grounded in the prevailing orthodoxies that characterize populism. © 2011 by the American Anthropological Association. Source

Brashears J.,Arizona State University | Brashears J.,San Diego Christian College | DeNardo D.F.,Arizona State University
Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology | Year: 2015

Facultative thermogenesis is often attributed to pythons in general despite limited comparative data available for the family. While all species within Pythonidae brood their eggs, only two species are known to produce heat to enhance embryonic thermal regulation. By contrast, a few python species have been reported to have insignificant thermogenic capabilities. To provide insight into potential phylogenetic, morphological, and ecological factors influencing thermogenic capability among pythons, we measured metabolic rates and clutch-environment temperature differentials at two environmental temperatures—python preferred brooding temperature (31.5 °C) and a sub-optimal temperature (25.5 °C)—in six species of pythons, including members of two major phylogenetic branches currently devoid of data on the subject. We found no evidence of facultative thermogenesis in five species: Aspidites melanocephalus, A. ramsayi, Morelia viridis, M. spilota cheynei, and Python regius. However, we found that Bothrochilus boa had a thermal metabolic sensitivity indicative of facultative thermogenesis (i.e., a higher metabolic rate at the lower temperature). However, its metabolic rate was quite low and technical challenges prevented us from measuring temperature differential to make conclusions about facultative endothermy in this species. Regardless, our data combined with existing literature demonstrate that facultative thermogenesis is not as widespread among pythons as previously thought. © 2015, Springer-Verlag Berlin Heidelberg. Source

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