Compare and contrast the jawless and jawed fish. How do scientists think the jaw first evolved
in fishes? Was the evolution of the jaw related to feeding? What will be an ideal response?
Various studies suggest that the jaw originally evolved from the first two or three anterior gill
arches of jawless fish. The jaw evolution may have been related to respiration. By evolving
joints in the forward gill arches, jawed fish could open their mouths wider. This would mean that
they could pump more water past the gills, increasing the oxygen intake, every time they opened
their mouths.
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What is the definition of a half-life?
A) The parent isotope half of a radiometric dating pair B) Half the time it takes for the parent isotope to decay to the daughter C) The time it takes for half of the parent isotope to decay to the daughter D) Half of the alpha particles necessary to decay at a steady rate
The belief that disasters have produced most of the major features of Earth is called
A. uniformitarianism. B. isostasy. C. metastable thresholds. D. catastrophism.
What type of magma is typically generated along hot spots?
a) mafic b) silicic c) intermediate d) both silicic and intermediate e) depends on the location of the hot spot
The ________ is an example of an active, continent-continent collision
A) Arabian Peninsula slamming into North Africa under the Red Sea B) westward movement of the South American plate over the Nazca plate C) northward movement of India into Eurasia D) northern movement of Baja California and a sliver of western California toward the Hawaiian Islands