8 research outputs found
The Church Online-The Impact of Online Social Networks on Church Congregations
This study will investigate the impact of online social networks for church members on those membersâ levels of engagement in the life of the church. Specifically, we endeavor to determine how and whether social networks for the church, including online calendars, discussion boards, blogs, photo sharing, and other such tools might contribute to behaviors such as greater involvement in church activities including worship, small groups, and volunteer leadership roles. Additionally, we will examine whether use of such tools also contributes to higher levels of giving, either to specific requests or to the routine fund raising of the church. Research hypotheses and a research methodology are proposed, along with directions for future research
Use of fieldâportable ultrasonography reveals differences in developmental phenology and maternal egg provisioning in two sympatric viviparous snakes
A thorough understanding of the life cycles underlying the demography of wild species is limited by the difficulty of observing hidden lifeâhistory traits, such as embryonic development. Major aspects of embryonic development, such as the rate and timing of development, and maternalâfetal interactions can be critical features of earlyâlife fitness and may impact population trends via effects on individual survival. While information on development in wild snakes and lizards is particularly limited, the repeated evolution of viviparity and diversity of reproductive mode in this clade make it a valuable subject of study. We used fieldâportable ultrasonography to investigate embryonic development in two sympatric garter snake species, Thamnophis sirtalis and Thamnophis elegans in the Sierra Nevada mountains of California. This approach allowed us to examine previously hidden reproductive traits including the timing and annual variation in development and differences in parental investment in young. Both species are viviparous, occupy similar ecological niches, and experience the same annual environmental conditions. We found that T. sirtalis embryos were more developmentally advanced than T. elegans embryos during June of three consecutive years. We also found that eggs increased in volume more substantially across developmental stages in T. elegans than in T. sirtalis, indicating differences in maternal provisioning of embryos via placental transfer of water. These findings shed light on interspecific differences in parental investment and timing of development within the same environmental context and demonstrate the value of field ultrasonography for pursuing questions relating to the evolution of reproductive modes, and the ecology of development.This article is published as Sparkman, Amanda M., Kenneth R. Chism, Anne M. Bronikowski, Lilly J. Brummett, Lucia L. Combrink, Courtney L. Davis, Kaitlyn G. Holden, Nicole M. Kabey, and David AW Miller. "Use of fieldâportable ultrasonography reveals differences in developmental phenology and maternal egg provisioning in two sympatric viviparous snakes." Ecology and evolution 8, no. 6 (2018): 3330-3340. doi: 10.1002/ece3.3928.</p
Data from: Convergence in reduced body size, head size, and blood glucose in three island reptiles
Many oceanic islands harbor diverse species that differ markedly from their mainland relatives with respect to morphology, behaviour, and physiology. A particularly common morphological change exhibited by a wide range of species on islands worldwide involves either a reduction in body size, termed island dwarfism, or an increase in body size, termed island gigantism. While numerous instances of dwarfism and gigantism have been well documented, documentation of other morphological changes on islands remains limited. Furthermore, we lack a basic understanding of the physiological mechanisms that underlie these changes, and whether they are convergent. A major hypothesis for the repeated evolution of dwarfism posits selection for smaller, more efficient body sizes in the context of low resource availability. Under this hypothesis we would expect the physiological mechanisms known to be downregulated in model organisms exhibiting small body sizes due to dietary restriction or artificial selection would also be downregulated in wild species exhibiting dwarfism on islands. We measured body size, relative head size, and circulating blood glucose in three species of reptilesâtwo snakes and one lizardâin the California Channel Islands relative to mainland populations. Collating data from six years of study, we found that relative to mainland population the island populations had smaller body size (i.e. island dwarfism), smaller head sizes relative to body size, and lower levels of blood glucose, though with some variation by sex and year. These findings suggest that the island populations of these three species have independently evolved convergent physiological changes (lower glucose set-point) corresponding to convergent changes in morphology that are consistent with a scenario of reduced resource availability and/or changes in prey size on the islands. This provides a powerful system to further investigate ecological, physiological, and genetic variables to elucidate the mechanisms underlying convergent changes in life history on islands
elgaria dryad
Elgaria multicarinata island dwarfism dat
coluber dryad
Coluber constrictor island dwarfism dat
pituophis dryad
Pituophis catenifer island dwarfism dat