Evidences and Mechanisms of Evolution (Part I) - Flashcards

A set of practice flashcards covering key concepts, mechanisms, and evidences of evolution from the lecture notes.

What is genetic drift?

Random changes in allele frequencies in a population from generation to generation due to chance; includes bottleneck and founder effects.

What is the bottleneck effect?

A drastic reduction in population size due to environmental factors, leading to loss of genetic diversity.

What is the founder effect?

A small group establishes a new population, causing allele frequencies to differ from the original population.

What is gene flow?

Movement of genes or individuals between populations, increasing genetic diversity.

What is mutation?

The primary source of genetic variation; changes in DNA sequence creating new alleles.

What is natural selection?

Differential survival and reproduction due to environmental pressures, leading to adaptation.

What is nonrandom (selective) mating?

Mating biased toward certain genotypes, increasing frequency of those traits.

What is the Modern Evolutionary Synthesis?

Integrated Darwinian natural selection with Mendelian inheritance; a comprehensive theory of evolution.

Who are key architects of the modern synthesis?

Theodosius Dobzhansky, Sewall Wright, Ernst Mayr, George Gaylord Simpson, G. Ledyard Stebbins.

According to the modern synthesis, what are the units of evolution?

Populations.

What is the central mechanism of evolution emphasized by the synthesis?

Natural selection.

What is gradualism in evolution?

Evolutionary change occurs through the accumulation of small changes over long periods.

What does the Hardy-Weinberg theorem describe?

A nonevolving population; allele and genotype frequencies remain constant from generation to generation in the absence of evolutionary forces.

In Hardy-Weinberg, what are p and q?

Allele frequencies for the two alleles; p for one allele, q for the other; p + q = 1.

What are the Hardy-Weinberg genotype frequencies for a two-allele system?

p^2 for homozygous dominant, 2pq for heterozygotes, q^2 for homozygous recessives.

If p = 0.8 and q = 0.2, what are the expected genotype frequencies?

RR = p^2 = 0.64; Rr = 2pq = 0.32; rr = q^2 = 0.04.

Who is known as the 'Father of Taxonomy'?

Carolus Linnaeus.

What is binomial nomenclature?

The two-word Latin scientific naming system for species.

What are homologous structures?

Structures with the same ancestry, different functions; divergent evolution.

What are analogous structures?

Structures with different ancestry, but similar function; convergent evolution.

What are vestigial structures?

Body parts reduced in function or unused, remnants of past ancestry.

What is fossil evidence for evolution?

Remains of extinct species showing past forms and transitional features.

What is biogeography evidence for evolution?

Distribution of species across the globe, reflecting evolutionary history.

What is embryology evidence for evolution?

Similar developmental traits across diverse organisms, indicating shared ancestry.

What is molecular evidence in evolution?

Genetic similarities among organisms that reveal evolutionary relationships.

Who published On the Origin of Species and The Descent of Man?

Charles Darwin (Origin of Species, 1859; The Descent of Man, 1871).