House sparrows in the northern part of north america are larger than those found in the southern regions. which mechanism of microevolution is more likely to be responsible for this?
founders effect
natural selection
genetic drift

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.