Introduction to Evolutionary Theory

These flashcards cover key concepts of evolutionary theory, figures in its development, and foundational principles such as natural selection.

Who helped the main outcome of evolutionary thought's development in the mid-19th century?

Natural selection was explained simultaneously by Charles Darwin and Alfred Russel Wallace.

What concept did John Ray propose regarding species?

Species can be differentiated by their ability to mate and produce offspring, making them 'reproductively isolated'.

Who is known for standardized binomial nomenclature in taxonomy?

Carolus Linnaeus.

What theory did Erasmus Darwin contribute to through poetry?

Evolution.

What major idea did Jean-Baptiste Lamarck propose regarding species?

Changes in the external environment lead to changes in activity patterns of animals, resulting in body modifications inherited by offspring.

What is catastrophism as explained by Georges Cuvier?

The idea that Earth's geological features result from sudden cataclysmic events.

What did Thomas Malthus argue regarding population growth?

Animal populations tend to increase, but resources remain the same, leading to competition.

What did Charles Lyell advocate in his work 'Principles of Geology'?

Uniformitarianism, meaning geological processes observed today also operated in the past.

What was significant about Mary Anning's contributions to paleontology?

She contributed to an early understanding of the evolution of marine life through her fossil discoveries.

What inspired Darwin's theory of natural selection?

Observations from animal breeders and the variations within populations.

What must happen for natural selection to take place?

Traits must be heritable.

What role does 'fitness' play in natural selection?

Fitness refers to the relative reproductive success of an individual.

What did Darwin believe at the outset of his journey on the HMS Beagle?

He believed in the fixity of species.

How did the environmental context determine traits in Darwin's theory?

The environmental context determines which traits are favorable.

What did Darwin observe in the Galapagos Islands?

Similar vegetation and animal species to the South American mainland, with variation among island populations.

What was Darwin’s main explanation for natural selection?

Individuals with favorable traits survive and reproduce, while those with unfavorable traits do not.

What did Alfred Russel Wallace contribute to evolutionary theory?

He independently proposed that species descended from older species influenced by the environment.

What is a characteristic of individuals who possess favorable traits?

They have greater fitness and contribute more to the next generation.

What is the impact of variation on a population in the context of evolution?

Variation among individuals can change the proportions of traits within a population.

What was the public reaction to Darwin's 'On the Origin of Species'?

It faced negative public opinion but was eventually supported by scientific communities.

What does 'selective pressure' refer to in natural selection?

Environmental factors that affect which traits are favorable.

How did the drought of 1977 affect the Galapagos medium ground finches?

Favoring birds with larger beaks that could crack open hard seeds.

What kind of traits must be present for natural selection to occur?

Heritable traits.

What does the term 'adaptive radiation' refer to?

The diversification of a common ancestor into a variety of forms suited to different habitats.

What does 'stabilizing selection' do?

It favors average phenotypes and acts against extreme traits.

What indicates 'directional selection' in a population?

It favors one extreme phenotype over others.

Define 'disruptive selection'.

It favors extreme traits at both ends of the spectrum while selecting against average traits.

What is the significance of 'deep time' in geology?

It refers to the time scale over which geological processes occur.

What is the main difference between artificial selection and natural selection?

Artificial selection is driven by human intervention, while natural selection is driven by environmental factors.

What did the research on drug-resistant bacteria illustrate?

The principles of natural selection in action through rapid adaptation to antibiotics.

What is meant by 'morphological variation'?

Differences in structure or form among individuals within a species.

In terms of evolutionary theory, what does 'extinction' imply?

The permanent loss of a species when it cannot adapt to changes in its environment.

How can competition among species lead to evolution?

It drives natural selection, as only the most fit individuals survive.

What did early evolutionary thinkers argue about species?

Many believed in the fixity of species before evidence of evolution emerged.

Who were some of the key early proponents of evolutionary ideas?

Linnaeus, Lamarck, Darwin, and Wallace.

What does 'inheritance of acquired characteristics' suggest?

It suggests traits acquired during an individual's life can be passed to offspring.

How did the concept of fitness expand beyond reproduction?

Fitness also considers the survival of offspring to reproductive age.

What is the relationship between mortality, fertility, and fitness?

Both affect an individual's fitness and ability to pass on traits.

What did the 1968 anti-evolution law changes signify?

A shift in legal acceptance and acknowledgment of evolutionary science.

How do natural selection and adaptation relate?

Natural selection leads to adaptation as species evolve traits that better suit their environments.

Why is studying evolution important according to the lecture?

It helps understand health, disease, and the dynamic processes of adaptation.