When the exposure of two different toxic chemicals produces a more severe effect than either one alone is called?

Alaska and northern canada have a diet rich in vitamin d and their skin color is darker than predicted on the basis of iv intensity at their latitude. explain the observation:

Simulating adaptations in a species in this activity, you will discuss in detail the adaptations in a species of rain forest plants. you will build a simulation that explains the changes in the traits of the plant population over 10 years. you will also establish a scientific explanation to justify the changes in the traits of the population, * time to complete: 1-2 hours part a an organism's adaptations are specific to its native environment. an organism that lives in a coniferous forest will have different adaptations compared to an animal that lives in a tropical rain forest. the following graphs show the temperature and precipitation throughout the year for two different forests: a coniferous forest in canada, and a tropical rain forest in belize. evaluate the graphs, and then explain why plants from these two ecosystems will have different adaptations. in your answer, explain the survival challenges that plants face in these two environments.

Explain the significance of thesaurus geographicus