Evolution and Natural Selection

Flashcards based on lecture notes about the theory of evolution and the scientists who contributed to it.

What are the two common meanings of the word 'theory'?

An educated guess and an explanatory model that accounts for a very large body of evidence.

Give examples of Scientific Theories.

Cell Theory, Particle Theory, Atomic Theory.

How are scientific theories founded?

On a large body of evidence that gives scientists great confidence in the theory.

According to lecture notes, what characteristics do scientific theories possess?

Tentative, open for revision, allow us to make accurate and precise predictions.

Define paleontology.

The study of ancient life through the examination of fossils.

What did Georges Cuvier find regarding rock strata and fossil species?

Each stratum is characterized by a unique group of fossil species, and the deeper the stratum, the more dissimilar the species are from modern life.

What evidence did Cuvier find from stratum to stratum regarding species?

New species appeared and others disappeared over the passage of time. This showed that species could become extinct.

Define Catastrophism.

The Earth experienced many destructive natural events in the past, such as floods and volcanic eruptions that killed numerous species.

What is Uniformitarianism?

The idea that geological processes operated at the same rates in the past as they do today.

What did Lyell reason about the age of the Earth?

If geological changes are slow and continuous, then Earth might be more than 6000 years old.

What did Jean-Baptiste Lamarck compare?

Current species of animals with fossil forms

Define Inheritance of Acquired Characteristics.

The idea that characteristics acquired during an organism's lifetime can be passed on to its offspring.

What is the theory of evolution by natural selection?

A theory explaining how life has changed, and continues to change, during Earth's history.

Define evolution.

The process of genetic change in a population over time.

What did Malthus propose?

Populations produced far more offspring than their environments could support.

What is natural selection?

The idea that the organisms that are the fittest leave the most offspring, so those organisms win the struggle for survival.

What is descent with modification?

The idea that life descended from some unknown organism and developed adaptations over time to better survive in local environments.

Briefly summarize Darwin's ideas.

Organisms compete for limited resources, individuals vary extensively, better-suited individuals survive to produce more offspring, and processes for change are slow and gradual.

Why did Darwin prefer 'descent with modification' over 'evolution'?

He felt 'evolution' implied progress, while natural selection has no set direction.