Origins of domestic dog in Southern East Asia is supported by analysis of Y-chromosome DNA

Global mitochondrial DNA (mtDNA) data indicates that the dog originates from domestication of wolf in Asia South of Yangtze River (ASY), with minor genetic contributions from dog–wolf hybridisation elsewhere. Archaeological data and autosomal single nucleotide polymorphism data have instead suggested that dogs originate from Europe and/or South West Asia but, because these datasets lack data from ASY, evidence pointing to ASY may have been overlooked. Analyses of additional markers for global datasets, including ASY, are therefore necessary to test if mtDNA phylogeography reflects the actual dog history and not merely stochastic events or selection. Here, we analyse 14 437 bp of Y-chromosome DNA sequence in 151 dogs sampled worldwide. We found 28 haplotypes distributed in five haplogroups. Two haplogroups were universally shared and included three haplotypes carried by 46% of all dogs, but two other haplogroups were primarily restricted to East Asia. Highest genetic diversity and virtually complete phylogenetic coverage was found within ASY. The 151 dogs were estimated to originate from 13–24 wolf founders, but there was no indication of post-domestication dog–wolf hybridisations. Thus, Y-chromosome and mtDNA data give strikingly similar pictures of dog phylogeography, most importantly that roughly 50% of the gene pools are shared universally but only ASY has nearly the full range of genetic diversity, such that the gene pools in all other regions may derive from ASY. This corroborates that ASY was the principal, and possibly sole region of wolf domestication, that a large number of wolves were domesticated, and that subsequent dog–wolf hybridisation contributed modestly to the dog gene pool

A Qualitative Examination Of Social Hierarchies Among Young Children

An intrinsic case study (Stake, 1995) was implemented to analyze data on social groups. In particular, naturally occurring social interactions were observed to decipher how cliques and hierarchies were displayed among groups of young children aged three to six. Participants were 16 pre-kindergarten children, four core staff members, three student teachers, and nine student workers or practicum students in a laboratory classroom setting. The fieldwork transpired over 28 visits, totaling approximately 93 hours, at a campus childcare facility referred to as The Center. Data collection consisted of observation, time samples, and semi-structured interviews. Distinct characteristics of this study included the uniqueness of the setting and the areas of data collection within the classroom. The researcher documented every 30 minutes where the children were located as well as with whom they were playing. The time samples resulted in 307 single interactions, 273 dyadic interactions, 131 triadic interactions, 58 quad interactions, and 60 interactions with five or more children which calculated to 829 total interactions documented in 182 time samples. The form and function of each relationship identified was explored through the use of observational field notes and semi-structured interviews with the children. In addition, supplemental perspectives from the core staff member interviews were included. Three sets of children had notably more dyadic interactions captured in the time samples. One triadic set of children had considerably more interactions captured and another set, although not as evident in the time samples, was identified by the core staff members. The researcher explored the relationships identified to determine the consistency within the roles, the impact of gender, and manner in which power was established. One small scale hierarchy transformed into an established hierarchy as two children floated in and out of the clique or when other children attempted to enter their play. Close examination of the functioning of this hierarchy led to the emergent themes of The Power of Exclusiveness and The Power of Exclusion. Suggestions for future research and implications for practice are detailed

The impact of notebooking on teacher candidates’ construction of knowledge

Teacher education preparation programs must adapt to changing science education reform movements that identify notebooking as an effective means to increase children’s’ science process skills and content knowledge. This study addresses the question, “What are the structures and thinking processes that teacher candidates utilize when writing in notebooks?” Specifically, how do they express their thoughts during an observational-based prompt writing experience in an undergraduate, integrated science and mathematics methods course? Sixteen teacher candidates at a Midwestern university in the United States completed an eight-week assignment during the spring 2012 semester using notebooks. Results indicate the participants could be placed into three distinct categories of processing and formatting the notebooks which are described in detail with supporting examples

The Impact of Notebooking on Teacher Candidates’ Construction of Knowledge

Teacher education preparation programs must adapt to changing science education reform movements that identify notebooking as an effective means to increase children’s’ science process skills and content knowledge. This study addresses the question, “What are the structures and thinking processes that teacher candidates utilize when writing in notebooks?” Specifically, how do they express their thoughts during an observational-based prompt writing experience in an undergraduate, integrated science and mathematics methods course? Sixteen teacher candidates at a Midwestern university in the United States completed an eight-week assignment during the spring 2012 semester using notebooks. Results indicate the participants could be placed into three distinct categories of processing and formatting the notebooks which are described in detail with supporting examples