What did the 1980 mount saint helens volcanic eruptions teach environmental scientists?
planting douglas fir trees was essential to recovering the forests.
many of the initial pioneering species actually survived the eruptions. seeding the slopes was necessary to prevent erosion.
salvage logging was essential to protecting the area from fire and insect threats.

Use the drop-down menu to complete the statement. an electron in the first energy level of the electron cloud has an electron in the third energy level. a. a lower energy thanb. a higher energy thanc. the same energy as

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

25. what does meiosis create? haploids or diploid? somatic cells or gametes?