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The High Altitude Water Cherenkov (HAWC) observatory is a very high energy gamma-ray detector located in Mexico. In late 2018, the HAWC collaboration completed a major upgrade consisting of the addition of a sparse outrigger array of 345 small water Cherenkov detectors (WCDs) surrounding the 300 WCDs of the main array and extending the instrumented area by a factor of 4. It provides an improved reconstruction of the showers whose core and footprint are not well contained in the array and increases the effective area in the range of a few TeV to beyond 100 TeV. This improvement in sensitivity will help to have a better understanding of the Galactic sources that accelerate particles up to the knee of the cosmic ray spectrum. In this contribution, we will show the current status, the performance, and the first results from the HAWC outrigger array. The High Altitude Water Cherenkov (HAWC) is a very-high-energy gamma-ray observatory located at 4100 m altitude on the volcano Sierra Negra in the state of Puebla in central Mexico. Bonnie, a Brindle Great Dane, with Sparkle, a Chihuahua mix. ­The relationship between people and dogs goes back at least 15,000 years, making dogs potentially the first animal to be domesticated. In that time, dogs have played many roles and performed many jobs for their human companions. Dogs come in a startling variety of shapes and sizes, but from the giant and noble Great Dane to the tiny and tenacious Chihuahua, they are all one species with one basic history. In this article, we'll explore where dogs came from and why they look and act the way they do. We'll also learn what recent genetic work has to tell us about our dogs. Talk about how to find the right dog for you. Canids are part of a larger group called Carnivora, which also includes bears, cats and seals. Fossils show us that Canidae split off from the common ancestors of Carnivora about 40 million years ago. From about 15 million years ago, we can subdivide Canidae into three subgroups: fox-like animals, wolf-like animals and South American canids, such as the maned wolf and crab-eating fox.|If you listen to an American swamp sparrow's song, you may notice it sounds the same from summer to summer. What you may not know, however, is that every song this little brown bird sings has probably been passed down for 1,500 years. Just as humans have traditions that are passed from generation to generation, these diminutive birds do, too, in the form of melodies. For a series of months, beginning in 2008, Lachlan and his researcher team recorded the songs of 615 male swamp sparrows (Melospiza georgiana) in the northeastern United States. The researchers then took a deep dive into the songs and, using acoustic analysis software, reduced the songs to individual notes. After measuring the degree of diversity among the melodies, the researchers realized only 2 percent of male swamp sparrows variated from the musical norm. Researchers then compared the deviation rate to recordings from the 1970s, and were able to estimate the oldest swamp sparrow songs dated back an average of 1,500 years. An analysis by Lachlan and his team found that, as fledglings, the birds had an uncanny knack for imitating the sounds of the adults birds of their species. This ability, paired with the birds' conformity bias - the tendency to take social cues from the actions of others - meant young birds memorized the songs they heard most often. In short, the American swamp sparrow created a song tradition that has lasted more than a millennium. Some types of birds develop distinct, area-specific dialects just like humans do. This often happens because populations of the same species are separated by geographic features such as bodies of water or mountains. Birds from one mountain can sound quite different from those of the same species the next mountain over. is trump winning

















































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