During which Eron did oxygen first appear in the atmosphere

Consider a population of snowshoe hares in montana. their fur color changes in response to changes in day length. during the long summer days, they have brown fur, but as the days shorten in the fall, their fur turns white in preparation for winter. then as the days get longer in the spring, their fur turns brown again. their fur coloration acts as camouflage from predators. as climate change brings warmer fall temperatures to montana, colder temperatures with snowfall are coming later in the year, and there may be less snowfall overall. as a result, the hares' fur color may be mismatched to the color of their surroundings, making them more visible to predators. which snowshoe hares would have a reproductive advantage in this changing environment? which snowshoe hares would have a reproductive advantage in this changing environment? hares that change color in response to day length, as the current population does hares with a mutation that prevents them from changing color from brown to white hares with a mutation that causes them to change color in response to temperature rather than day length hares with a mutation that prevents them from changing color from white to brown

Why might have people followed the rivers to find their way into asia

According to the earth science reference tables, during which geologic time period were the continents of north america,south america, and africa closest together?