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I don't know about the specific cues that American robins use for migration. This species is also both a short range (e.g. between states or to lower altitudes) and long range migrant (e.g. Florida & Mexico), so the cues that they use can probably differ between overwintering populations. There are also year-round populations of robins in the US, but ...


2

The problem of how to infer species distributions from scattered species occurrences is common in ecology, and there exists a number of methods to construct distribution maps. As a start, you should have a look at Species Distribution Models (SDMs) using regressions models or Maxent, and the paper by Elith et al (2009) is a good starting point and a standard ...


5

The fermentation is relatively complex, as quite a number of different bacterial species and yeast live in the Kefir grains. These are made of of the polysaccheride kefiran which immobilizes the bacteria (in contrast for example to yoghurt). The microbes live symbiotic on this matrix. According to the references a number of different microorganisms has been ...


4

Well essentially the added Lactobacillus species ferment lactose and other sugars to lactic acid, thus lowering the pH of the product (they take up lactose use it as an energy source under anaerobic conditions and secrete lactic acid). This gives the kefir and other fermented milk products their sourness. Also the lower pH prevents many other bacteria from ...


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I'm not a specialist in this area, but I would guess that the length of day-light periods compared to night time could be a good trigger. This is quite independent of the weather, is quite constant (even though length of days is known to have changed through over the millions of years past since the formation of earth).


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I think the lack of sea ice coverage would point you somewhere- even with the maximum sea ice coverage picture, the SW corner of Greenland has next to none, which may impact the carrying capacity for both bears and prey animals on that narrow strip of land between the ice cap and the sea- less space and less things to hunt, less ways to get around, etc. And ...



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