Subject
Earth sciences
6
Geology
6
Erosion
5
Ocean
5
Continental crust
4
Earth (Planet)
4
Earth (Planet) Core
4
Earth (Planet) Crust
4
Earth (Planet) Surface
4
Earthquakes
4
Glaciers
4
Groundwater
4
Plate tectonics
4
Volcanoes
4
Continental drift
3
Minerals
3
Mountains
3
Rocks
3
Ethnology
2
Faults (Geology)
2
Geophysics
2
Seismology
2
Animal intelligence
1
Apes Psychology
1
Archaeology
1
Astronomy
1
Beaches
1
Bonobo Psychology
1
Ceremonial exchange
1
Child development
1
Children Diseases Prevention
1
Chimpanzees Psychology
1
Civilization History
1
Coasts
1
Computers and children
1
Continental shelf
1
Deserts
1
Floods
1
Fossil fuels
1
Genealogy
1
Genetics Research
1
Geological time
1
Hominids Psychology
1
Human beings Migrations
1
Igneous rocks
1
Internet addiction
1
Internet and children
1
Kawelka (Papua New Guinean people)
1
Knowledge, Theory of
1
Loma Prieta Earthquake, Calif., 1989
1
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