Selection pressures operate on populations in such a way as to increase the overall fitness of a population. An example of this can be seen in the birth weights of human babies. For humans, giving birth is a special, but often traumatic, event. In a study of human birth weights, it is possible to observe the effect of selection pressures on a population. For humans, if an infant is born weighing 1kg, just 20% survive. If the birth weight increases just 1⁄2 kg (1.5kg), then the survival rate is 70%. As birth weight increases to 2.0kg, survival rate is 88% and it is 96% at 2.5kg. Both 3kg and 4kg have a survival rate of 97%, while the survival rate is 98% for 3.5kg babies. At 4.5kg the survival rate decreases to 93% and it is 85% for 5kg babies. Fill in the data table below and graph the information using the appropriate graph.

Which description shows competition in an environment? an organism that feeds on some food an organism that finds a place to sleep three organisms of the same species living in an area three organisms battling over limited resources

Why do mountaineers become breathless as they reach high altitudes

98 points you will be galileo perform the experiment to determine if objects with different mass fall at the same, or different, rates in the air and in a vacuum. before you conduct your experiment, you need to form a hypothesis. a hypothesis is a prediction of what you think will happen in the experiment. the hypothesis is a statement that describes “if” a certain set of circumstances are present “then” there will be a specific result that will occur. record your hypothesis here: record the results from step one of the experiment (dropping the objects in the air): first trial: second trial: third trial: record the results from step two of the experiment (dropping the objects in a vacuum): first trial: second trial: third trial: did the experiment support your hypothesis? using the data from your experiment, describe why you believe your hypothesis was either proven or disproven. what forces were acting on the objects dropped in the air? what force was acting on the objects dropped in the vacuum? part two: comparing forces choose two forces and compare and contrast these forces. you must provide two ways that they are alike and two ways that they are different. you may make a list, write in paragraph form, or make a chart. choose two forces and compare and contrast these forces. these must be different forces than used in the prior question. provide two ways that they are similar and two ways that they are different. you may make a list, write it out, or make a chart.