5-1-3 Evolutoin by Natural Selection

Question 1

Two men, working independently, each came up with similar ideas about how life changed over time as a result of natural selection. Who are they?

Answer 1

Charles Darwin and Alfred Wallace

Question 2

In their work on evolution, what did Charles Darwin and Alfred Russel Wallace study and observe?

Answer 2

They both traveled and made careful field observations of living organisms and their environments.

Darwin collected plant, animal, and fossil specimens. He also made extensive geological observations.

Wallace’s work took him to South America and Indonesia where he collected many specimens and recorded his observations.

Question 3

In addition to making their own observations, Darwin and Wallace made use of the work from two other people in developing their theories. Who are those people?

Answer 3

Charles Lyell: slow geological change over long periods of time.

Thomas Malthus: a population tends to grow geometrically until its size reaches an upper limit.

Question 4

What are the 4 main points of Darwin’s evolution theory?

Answer 4

1. Adaptation: all organisms adapt to their environments.
2. Variation: all organisms are variable in their traits
3. Over-reproduction: all organisms tend to reproduce beyond their environment’s capacity to support them.
4. Natural Selection: since not all organisms are equally well adapted to their environments, some will survive and reproduce better than others.

Question 5

Darwin based point #3 (Over-reproduction) of his theory on who’s work?

Answer 5

Thomas Malthus. Malthus showed that a population tended to grow geometrically until its size reached an upper limit of the environment’s capacity to support them.

Question 6

Darwin’s 4th principle, natural selection, is also referred to as …

Answer 6

“survival of the fittest”. The phrase refers to the reproductive success of the organisms, not just their relative strength or speed.

Question 7

What are the 5 main points of Wallace-Darwin Theory?

Answer 7

1. Individuals in a population have variable levels of agility , size, ability to obtain food, success in reproducing.
2. left unchecked, populations tend to expand exponentially, leading to a scarcity of resources.
3. In the struggle for existence, some individuals are more successful than others, allowng them ot survive and reproduce.
4. Those organisms best able to survive and reproduce will leave more offspring than those that are less successful.
5. Over time there will be heritable changes in phentype (and genotype) of a species, resulting in a transformatin of the original species. The new species will be similar to, but distinct from, its parent species.