Evolution works by
tinkering with existing structures
Hox genes are thought to play an important role in the development of different morphologies because they
provide positional information in the embryo.
The atmosphere of early Earth probably contained no O2 until the emergence of organisms that used
water as an electron source for photosynthesis
Radiometric dating allows us to
indirectly date fossils up to billions of years old based or minerals in surrounding volcanic strata.
The oldest fossils usually are found in
the deepest strata
Earth probably formed __________ and the first life evolved as early as _________
4.5 billion, 3.9 billion
RNA is believed to be the genetic material because RNA has both
informational storage and catalytic properties
Miller and Ureys experiments that attempted to recreate conditions on early Earth were significant because they showed that
Organic molecules such as amino acids could be produced from inorganic molecules