In the pleistocene period 10,000 years ago, there was a remarkable extinction of vertebrates in many continents, which may explain why the cheetah has famously low levels of genetic variation. which evolutionary mechanism does this reflect?
a: natural selection
b: bottleneck effect
c: founder princable

blue stars have the highest surface temp

stellar distances are usually expressed in light-years

the measure of a star's brightness is called magnitude

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when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.