(C) (i) Identify AND describe the geological action that is occurring at C in
the diagram. (1 point maximum) Feature C is a hot spot—a place
where the temperature is higher than average such that localized
melting occurs. The molten rock, being less dense due to its
temperature and state of matter, rises and forms a volcano. Over
geologic time, the hot spot remains constant, whereas the lithospheric
plate moves over it causing a chain of volcanoes.(ii) Give an example of geological feature C occurring on Earth. Only 1
example is required. (1 point maximum) Possible answers include:
■ Hawaiian Islands
■ Iceland
■ The Azores
■ Yellowstone (Wyoming)
■ Galápagos(b) Maximum 2 points total for describing two ways.
Describe two ways in which evolution and/or speciation may occur as a
consequence of plate tectonics. (1 point maximum for first way and 1 point
maximum for second way) (1) A divergent plate boundary could cause one
landmass to be divided into two or more distinct parts, perhaps separated by
an ocean. For example, identical fossils can be found on the east coast of
South America and the west coast of Africa, indicating that these were once
the same connected landmass. After these two continents diverged, different
species would evolve from this common ancestor as a reaction to the different
environments and consequent pressures on the different landmasses.(2) Another possible way could be faulting, which, as a result of plate
tectonics, could cause a river to be diverted. The new path of the river
could divide a population into two and serve as a geographic barrier
preventing gene flow. Different conditions in geographically separated
regions would eventually lead to the evolution of different species as each
population adapted to its environment in different ways.(c) Maximum 2 points total for explaining short-term and long-term climate
change.
Explain how the eruption of Mount Pinatubo might affect short-term and
long-term climate change. (1 point maximum for explaining a short-term