ANT3451 Midterm UF Summer 17

True Natural selection is the differential survival and reproduction of individuals due to differences in phenotype.

False Gene flow is the transfer of genetic material from one population to another, decreasing genetic variation between the populations and making them more similar over time.

True The Hardy-Weinberg equilibrium states that genotype frequencies will remain steady from generation to generation in a population not impacted by other evolutionary influences (such as mutation or gene flow).

False In the 19th century, Gregor Mendel deduced that genes come in pairs (alleles) and are inherited as distinct units, one from each parent, disproving the theory of blended inheritance popular at that time.

False Mendelian inheritance fails to account for more complicated patterns of inheritance including incomplete dominance, genes with multiple alleles, and polygenic traits.

mutations Correct, we can determine the point in our history when we diverged from other primate species by looking at the accumulation of genetic mutations.

mutations Mutation is the only mechanism of genetic change that introduces new genetic material.

Natural selection Natural selection tells us that more organisms are produced than can survive due to limited resources; better-adapted individuals are more likely to survive and reproduce.

Change in allele frequencies from one generation to the next Evolution is the change in allele frequencies from generation to generation; incorporating a variety of mechanisms of genetic change (natural selection, gene flow, genetic drift, and mutation). Although natural selection is a means of differential reproduction, evolution is not directional.

Pleiotropy Genes that affect multiple, sometimes apparently unrelated, phenotypes are pleiotropic genes.

Particulate Heredity Particulate Heredity states that phenotypic traits are passed from parent to offspring as "discrete particles," today known as genes. When first proposed, the principle contradicted the long-standing belief in blending inheritance.

one allele is dominant and the other is recessive Heterozygous genotypes consist of one dominant and one recessive allele (Rr) while homozygous genotypes consist of two dominant (RR) or two recessive alleles (rr).

Gene flow The multiregional evolution hypothesis suggests that Homo sapiens emerged after the diaspora from Africa and that gene flow between the dispersed populations allowed for the continued evolution of a single human species.

DNA Correct, all of our genetic information is passed down from our parents through DNA. DNA is the mechanism of biological inheritance in human beings.

Nonrandom mating The four forces of evolution are natural selection, mutation, gene flow, and genetic drift.

True

False

False

True

True

Traits vary independently of one another

Traits are distributed continuously

Africa

1.6-2 mya Homo erectus was the first of its genus to leave Africa approximately 1.6-2 million years ago.

African apes & humans Humans are most closely related to chimpanzees, followed by gorillas, both of which are African apes. All three are members of the subfamily Homininae. Humans are more distantly related to Asian apes, including orangutans and gibbons.

150,000 - 200,000 years ago in Africa The earliest fossil evidence of anatomically modern humans is found in East Africa and dates to around 195 kya.

Pleiotropy

Their traditional diet of fish and marine mammals

The ratio of a body's volume to surface area

- It does not describe the extent to which a trait is under genetic control - It is a relative measure of the genetic vs. environmental variation within any given population - Estimates of heritability within groups cannot be used to explain differences between groups