Squirrels in different areas can have a range of fur colors including gray, brown, and black. For a number of years, the majority of squirrels in North America have had a gray fur color. Scientists have recently observed an increase in squirrels with black fur color from 0-5 percent of the squirrel population to as much as 25 percent of the squirrel population in some areas. Part A
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Which statement best describes how squirrels with gray fur color and squirrels with black fur color have adapted to these areas in recent years?
A
Squirrels with gray fur color have adapted traits that are better suited for these areas than the traits in squirrels with black fur color.
B
Squirrels with black fur color have adapted traits that are better suited for these areas than the traits in squirrels with gray fur color.
C
Squirrels with gray fur color and squirrels with black fur color have adapted equally to living in these areas.
D
Squirrels with gray fur color and squirrels with black fur color both have adapted traits that are less suited to living in these areas.

primary succession begins with a bare rock and ends with a forest secondary succession begins after a natural disaster where there is a temporary setback after a forest fire or local destruction, but the surrounding area can fill in

a fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing energy originating in ancient photosynthesis.[1] the age of the organisms and their resulting fossil fuels is typically millions of years, and sometimes exceeds 650 million years.[2] fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas.[3] other commonly used derivatives include kerosene and propane. fossil fuels range from volatile materials with low carbon to hydrogen ratios like methane, to liquids like petroleum, to nonvolatile materials composed of almost pure carbon, like anthracite coal. methane can be found in hydrocarbon fields either alone, associated with oil, or in the form of methane clathrates.

the theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the earth's crust over millions of years was first introduced by andreas libavius "in his 1597 alchemia [alchymia]" and later by mikhail lomonosov "as early as 1757 and certainly by 1763".[4] the first use of the term "fossil fuel" was by the german chemist caspar neumann, in english translation in 1759.[5]

in 2017 the world's primary energy sources consisted of petroleum (34%), coal (28%), natural gas (23%), amounting to an 85% share for fossil fuels in primary energy consumption in the world.[6] non-fossil sources in 2006 included nuclear (8.5%), hydroelectric (6.3%), and others (geothermal, solar, tidal, wind, wood, waste) amounting to 0.9%.[7] world energy consumption was growing at about 2.3% per year. in 2015 about 18% of worldwide consumption was from renewable sources.[8]