Question

which of the following graphs best displays population size over time of an r - selected species that has just colonized a new habitat with abundant resources?

Explanation:

r - selected species are characterized by high growth rates, especially when colonizing new habitats with abundant resources. Their population size initially increases rapidly (exponential - like growth phase). Graph A shows a curve that starts with a sharp decline (which might be mis - interpretation, but considering the context of population growth in new habitat, if we assume the y - axis is population size and x - axis is time, for a new colonization, the population should grow. However, if we consider the standard population growth models, for r - selected species in a new habitat with abundant resources, they will have a period of rapid growth. Among the given options, graph A (assuming the y - axis is population size and x - axis is time, and the curve is actually a growth curve, maybe the orientation was mis - drawn) is the best fit as it shows a trend that can be associated with the initial rapid increase (in a proper orientation) of an r - selected species in a new habitat. Graph B shows a more fluctuating and then decreasing trend which is not typical for new colonization with abundant resources. Graph C shows excessive oscillations which are not characteristic of the initial colonization phase of r - selected species.

Answer:

A.