Describe the evolution of fish in the Paleozoic. What will be an ideal response?
The most primitive vertebrates were the jawless fish, the ostracoderms. They had poorly developed
fins, an external covering of body armor, and were extinct by the end of the Devonian. Jawless fish
could only feed on detritus, but jawed fish, the acanthodians and placoderms, could chew food and
become active predators. Acanthodians appeared in the Lower Silurian with large spines, scales
covering much of the body, and reduced body armor. Placoderms evolved during the Late Silurian and
had considerable variety.
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List the eight essential changes in the way people perceive and use their environments necessary to meet sustainable development
What kind of erosion produces sinkholes?
A) wind erosion B) groundwater erosion C) ocean wave erosion D) stream erosion
Geologists use ____ and their knowledge of present-day depositional processes to make determinations about a rock's depositional environment
A)the principle of uniformitarianism B)the principle of catastrophism C)lunar geology D)anthropology E)archeology
"If domestic fuel prices rise to $5 per gallon, growth will slow significantly and our quality of life will decline." This philosophy is consistent with ________ economics
A) environmental B) neoclassical C) ecological D) social E) subsistence