What is a probable reason why land species represent 86 of the world's species, whereas marine species only represent 14?
a) There is more land on Earth than there is ocean.
b) Water slows down the evolutionary process.
c) The more variable the environment, the more chances there will be for new species to form, and the ocean is more stable than the land environment.
d) An underwater cataclysmic event during the Pleistocene killed many marine species, which reduced the previously abundant marine species count to less than the number of land species.
Question 2
Many of the unique properties of water, such as cohesion and its reputation as a universal solvent, come from its atomic structure. What causes these properties?
a) Atoms in water molecules are stuck together with atomic bonds.
b) Atoms in water molecules are stuck together with covalent bonds.
c) Water molecules are electrically polarized.
d) Water molecules contain sodium (Na) ions that break down substances.
e) Many other ions can substitute for the hydrogen (H) atoms in a water molecule.
Comparison of the radius of fruits produced by native and introduced species of Sapindaceae
The nitrogen cycle. Numbers represent fluxes as 1012 g N per year (data from Schlesinger 1991, after
World fossil fuel consumption since 1950
Distribution of the Old World monkeys.
Cretaceous world
World Population, 1850–2150