What are terranes? How are they recognized? What role did accretion of terranes play in the growth of western North America?
Small accreted lithospheric blocks, called terranes, are found in many mountain systems. They are composed of such different fossils, stratigraphy, structural trends, and paleomagnetic properties from the surrounding rocks and craton that geologists think that they were carried great distances as parts of other plates until they collided with other terranes and continents. More than 100 different-sized terranes were added to the western margin of North America during the past 200 million years.
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The wood thrush makes its nest in woodlands in the northern and eastern United States. As patches of woods become smaller, increasing numbers of wood thrush nests have eggs laid in them by the brown-headed cowbird. Cowbirds live in open fields and are
nest parasites; the female cowbird flies up to an unattended nest, quickly lays an egg in it, and leaves the host parents to raise their "adopted" young. Wood thrushes are decreasing in numbers because ________. A) habitat fragmentation makes it easier for cowbird parasitism to occur B) pollution of the open fields has caused a change in cowbird behavior C) cowbirds are an invasive species that is rapidly increasing D) climate change is reducing nest site availability E) overharvesting in the open fields has driven the cowbirds into the woodlands
Which of the following plays a role in the shaping of Earth's surface?
A) gravity B) the action of wind, water, and ice C) the radioactive decay of atoms D) gravity, wind, water, and ice, and radioactive decay E) gravity and wind, water, and ice only
When Russia recently invaded Georgia due to conflict over South Ossetia, NATO intervened militarily to expel the Russians
Indicate whether the statement is true or false
The highest rates of AIDS infection are in:
A) Northern Africa B) Southern Africa C) Western Africa D) Eastern Africa E) none of the above