Frogs are only one example of the many species that have become endangered due to climate change. Scientists project that a rise of 1.5-2.5°C in global average temperatures will lead to the extinction of 20-30% of Earth's species. Species that live on isolated islands, northern latitudes, and at high elevations are at the highest risk. A rise of 3.5°C would eliminate the habitat of almost half of the vertebrate species endemic to mountain habitats.

The organisms that make up an ecosystem interact in complex ways. As a result, a seemingly small change in the distribution of one organism can have significant effects on the rest of the system. Many organisms, like frogs, adapt to climate change by shifting northward. Boreal forests, for example, are moving north at a rate of 100-150 km per degree of temperature increase.

Unfortunately, not all members of an ecosystem respond to a shift in climate at the same rate. This disrupts many ecosystems as some species are forced to migrate away from components of the ecosystem that they rely on, such as ideal food sources. Newcomers to an area also put stress on existing populations by competing for limited resources.

Question: Look at the food web below. What would happen to the rest of the web if the frog was removed? What would happen if more frogs migrated into the area where this food web is in effect?