“Study: Small Dogs Came From The Middle East - Redorbit.com” plus 1 more |
| Study: Small Dogs Came From The Middle East - Redorbit.com Posted: 24 Feb 2010 07:35 AM PST Message from fivefilters.org: If you can, please donate to the full-text RSS service so we can continue developing it. Posted on: Wednesday, 24 February 2010, 09:40 CST A genetic study has found that small domestic dogs probably originated in the Middle East more than 12,000 years ago. Researchers writing in the open access journal BMC Biology traced the evolutionary history of the IGF1 gene, finding that the version of the gene that is a major determinant of small size probably originated as a result of the domestication of the Middle Eastern gray wolf. Melissa Gray and Robert Wayne, from the University of California, Los Angeles, led a team of researchers who surveyed a large sample of gray wolf populations. She said, "The mutation for small body size post-dates the domestication of dogs. However, because all small dogs possess this variant of IGF1, it probably arose early in their history. Our results show that the version of the IGF1 gene found in small dogs is closely related to that found in Middle Eastern wolves and is consistent with an ancient origin in this region of small domestic dogs". Previous archeological work in the Middle East has unearthed the remains of small domestic dogs dating to 12,000 years ago. Sites in Belgium, Germany and Western Russia contain older remains (13,000-31,000 years ago), but these are of larger dogs. These findings support the hypothesis put forward by Gray and colleagues that small body size evolved in the Middle East. Reduction in body size is a common feature of domestication and has been seen in other domesticated animals including cattle, pigs and goats. According to Gray, "Small size could have been more desirable in more densely packed agricultural societies, in which dogs may have lived partly indoors or in confined outdoor spaces". The IGF1 small dog haplotype is derived from Middle Eastern gray wolves. Melissa M. Gray, Nathan B. Sutter, Elaine A. Ostrander and Robert K. Wayne. BMC Biology (in press) --- On the Net: Five Filters featured article: Chilcot Inquiry. Available tools: PDF Newspaper, Full Text RSS, Term Extraction. |
| Marine biology allows students to dig deep into science - Asbury Park Press Posted: 25 Feb 2010 01:00 AM PST Message from fivefilters.org: If you can, please donate to the full-text RSS service so we can continue developing it. Every day truly seems like an adventure when you attend the Marine Sciences classes at Holmdel High School. Mark Schroeter, 53, of Ocean has been teaching this course ever since he began teaching at Holmdel High School 26 years ago. With hands-on experiments and field trips, this class helps students understand the connection between organisms and their environment. "Here, we are a shore community," Schroeter says. "We're only 18 miles from the shoreline, so we really try to take advantage of the ocean and the environments that we go to. So with this field trip-oriented course, students learn things that are not taught in the classroom because you cannot duplicate what you see out on the field." Recently, the class has taken trips to the beaches of Asbury Park and Sandy Hook to study wildlife, wave dynamics, beach erosion and more. The students collect data, share it with the class and analyze their results. "I find it so cool that we apply what we learn to real life with these field trips, so it doesn't just feel like we are memorizing useless facts," says senior Erik Shirvanian, 17. "I really enjoy all the experiments that come with this science, just getting your hands all dirty," says senior Brendan Tschaen, 17. "For example, today we just dissected a fish! I mean you can't do this in every class." This class is taught without a textbook, so experiments play a huge role in the curriculum. "Without the textbook to rely on, I (have) to make sure to maintain the students' attention and motivate them to take notes," Schroeter says. Schroeter has earned the respect of his peers. "He is very modest about it, but he knows more about these marine science topics than most college professors I know," says biology and AP environmental science teacher Jonathan Cole, a resident of Atlantic Highlands. Five Filters featured article: Chilcot Inquiry. Available tools: PDF Newspaper, Full Text RSS, Term Extraction. |
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