Bio 105: Evolution: Genes & Darwin

What is natural selection?

is the process by which individuals with favorable traits survive longer and reproduce more than those without those traits.

What is fitness in the context of evolution?

the ability of an organism to survive and reproduce in its environment.

Define evolution.

is the accumulated change in the traits of a population over many generations, primarily caused by natural selection.

What are genes?

heritable instructions found within DNA that determine the appearance and behavior of an organism.

Who was Charles Darwin?

Charles Darwin was a key evolutionary scientist known for his theory of evolution and his observations during the voyage on the HMS Beagle.

What was the goal of Darwin's voyage on the HMS Beagle?

The goal was to explore the Southern Hemisphere and gather observations that would later contribute to his theory of evolution.

What is Darwin's theory of evolution?

populations contain variation that is heritable, organisms compete for resources, differ in reproductive success, and adapt to changing environments.

How do genes contribute to evolution?

Genes store heritable traits that can vary within a population, influencing the evolutionary process.

What creates variations within genes?

Variations within genes can be created through mutations and genetic recombination.

What happens to harmful, beneficial, and neutral variations in a population?

Beneficial variations may increase in frequency due to natural selection, harmful variations may decrease, and neutral variations may remain stable.

Is the goal of variation to improve a species' success?

No, variation is generated randomly and does not have a predetermined goal.

How is adaptation related to natural selection?

the process by which a species becomes better suited to its environment through natural selection.

What impact has natural selection had on the St. Anthony's frog in Chernobyl?

Natural selection has led to adaptations in the St. Anthony's frog population due to environmental changes caused by radiation.

What is the significance of the Archaeopteryx fossil?

The Archaeopteryx fossil is significant as it represents an intermediate form between dinosaurs and birds, challenging the idea of the fixity of species.

What is the Fixity of Species hypothesis?

every species has a perfect form and does not change over time.

Who founded the science of paleontology?

Baron Georges Cuvier founded the science of paleontology.

What did Cuvier's findings about fossils suggest?

Cuvier's findings suggested that some species had become extinct and that fossils differed between layers of sediment.

What are heritable traits?

characteristics that can be passed from parents to offspring through genes.

What is the role of natural variation in evolution?

provides the raw material for natural selection to act upon, leading to evolutionary change.

How does natural selection explain the example of moths and camouflage?

Moths with colors that better match their environment are less likely to be eaten by predators, leading to increased survival and reproduction.

What is the shell color gene?

A gene that determines the color of shells in a population.

What is an allele?

A unique version of a gene.

What creates variation within a population?

Random mutations to genes.

How does natural selection operate?

It operates on variations already present in the population's genes.

What happens to harmful variations in a population?

They are eliminated by natural selection.

What happens to beneficial variations in a population?

They are maintained or increased over generations.

What happens to neutral variations in a population?

They are maintained because they are ignored by natural selection.

What is an adaptation?

A modification that a species uses to survive in a particular environment.

Give an example of an adaptation.

The Venus flytrap captures and digests flies to obtain nitrogen in nitrogen-poor soil.

What is the significance of Darwin's voyage?

It led to his development of the theory of evolution through natural selection.

What are the key components of Darwin's theory of evolution?

1. Populations contain heritable variation. 2. Organisms compete for resources. 3. Organisms differ in reproductive success. 4. Organisms adapt to changing environments.

What is the role of genes in evolution?

the units of heritable traits that contribute to variation in populations.

How does natural selection affect the St Anthony's frog in Chernobyl?

Darker pigmentation in frogs has been observed, which may provide protection against radiation damage.

What is the misconception about variation in species?

The misconception is that variation aims to improve species success; in reality, it is generated randomly.

What is the impact of competition on populations?

If every individual survived, a population would exhaust its resources.

What is the relationship between adaptations and natural selection?

Adaptations result from natural selection favoring beneficial variations.

What is the example of moths and camouflage related to fitness?

Light moths have greater fitness in a light bark forest because they are less visible to predators.

What is the definition of heritable variation?

Variation that can be passed down from one generation to the next.

What is the effect of random mutations on a population?

They create new variations that can be subject to natural selection.

What is the significance of the term 'fitness' in evolution?

Fitness determines an organism's success in surviving and reproducing.

What happens if a new version of a trait does not change the amount of resources used?

It may not significantly impact the population's survival or reproduction.

What is the importance of studying variations in genes?

Understanding variations helps explain how species adapt and evolve over time.

What is the role of competition in evolution?

Competition drives natural selection by determining which organisms survive and reproduce.

What are the four key ideas of Darwin's theory?

1. Heritable variation exists. 2. Competition for resources occurs. 3. Reproductive success varies. 4. Adaptation to environmental changes happens.