Living Environment Translated Arabic 2014 | Page 88

Unit 7: Evolution
A. Vocabulary
1. Evolution- a change in a species over time
2. The Earth is believed to be approximately 4.5 billion years old.
3. Jean B. de Lamarck – a scientist who proposed the Theory of Use
and Disuse. He said that changes in the environment caused the
organism’s behavior to change, leading to greater use or disuse
of a structure or organ. This was proven to be incorrect.
4. Charles Darwin- a scientist who proposed the Theory of Natural
Selection which includes the concepts of overproduction,
variation, and competition
5. Natural Selection – a process by which organisms with traits best
suited to their environment are more likely to survive and
reproduce
6. Variation- an inherited trait that makes an individual different
from other members of the same species and results from a
mutation in the organism’s genes.
7. Adaptation- any variation that makes an organism better suited
to its environment
8. Gradualism- a model describing evolution as a slow process by
which one species changes into a new species through a
continuing series of mutations and variations over time.
9. Punctuated equilibrium- a model describing the rapid evolution
that occurs when mutation of a few genes results in a species
suddenly changing into a new species
10.Fossil- a trace of an organism from the past
11. Overproduction- producing more offspring than can reasonably
survive
12. Geographic isolation- separation between populations due to
physical barriers
13. Sedimentary rock- a type of rock that is most likely to contain
fossils and is formed when layers of sand, silt, clay, or mud are
cemented and compacted together