The trees in a forest were cut down to make room for a housing development. What must the organisms that lived in the forest do to survive?
A.
B.
The organisms must mate with similar species in nearby forests.
The organisms must migrate to another area with fewer resources.
The organisms must stop reproducing to limit the strain on their resources.
The organisms must compete with each other for the limited resources.
D.

Sand spinifex grass is adapted to growing on sand dunes. it is a rapidly spreading plant and the creeping runners produce new root systems. which of these best explains the benefits of these features? a. it limits water loss through the leaves. b. it provides support by anchoring the plant. c. it protects the plant from predators. d. it allows the plant to tolerate salt. reset submit

To answer this question, researchers studied populations of the dusky salamander (desmognathus ochrophaeus) living on different mountain ranges in the southern appalachian mountains. the researchers tested the reproductive isolation of pairs of salamander populations by leaving one male and one female together and later checking the females for the presence of sperm. four mating combinations were tested for each pair of populations (a and b)—two within the same population (female a with male a and female b with male b) and two between populations (female a with male b and female b with male a). the proportion of successful matings for each mating combination was measured. for example, when all the matings of a particular combination were successful, the researchers gave it a value of 1; when none of the matings were successful, they gave it a value of 0. then the researchers calculated an index of reproductive isolation that ranged from 0 (no isolation) to 2 (full isolation). the reproductive isolation value for two populations is the sum of the proportion of successful matings of each type within populations (aa + bb) minus the sum of the proportion of successful matings of each type between populations (ab + ba). the table provides data for the geographic distances and reproductive isolation values for 27 pairs of dusky salamander populations.

In 1992, hurricane andrew left a wake of destruction through florida. one victim of the storm was a reptile-breeding facility. over 900 burmese pythons were set free, and today thousands of pythons live in florida. these pythons are an invasive species, or a harmful species not native to the region. 1. what impacts do you think the burmese pythons might have on local ecosystems