Changes in Allele Frequency
What is the definition of allele frequency?
Allele frequency is the proportion of a specific allele among all allele copies in a population.
What is speciation?
Speciation is the evolutionary process by which new biological species arise.
What is a phylogenetic tree?
A phylogenetic tree is a diagram that represents evolutionary relationships among species based on common ancestry.
Describe two key characteristics that distinguish hominins from other primates.
Key characteristics distinguishing hominins from other primates include bipedalism (walking upright) and a more advanced cognitive ability.
What is bioethics, and why is it important in the context of evolutionary studies?
Bioethics is the study of ethical issues arising from biological and medical research, important for guiding responsible research practices and addressing societal concerns.
Describe how natural selection can lead to changes in allele frequency in a population.
Natural selection can lead to changes in allele frequency by favoring individuals with advantageous traits, leading to higher reproductive success and passing those traits to the next generation.
Differentiate between allopatric and sympatric speciation.
Allopatric speciation occurs when populations are geographically isolated, while sympatric speciation occurs without geographic barriers, often through polyploidy or behavioral differences.
How do scientists determine the relatedness of different species?
Scientists determine relatedness through comparative anatomy, molecular data (DNA sequences), and fossil records.
What evidence supports the idea of bipedalism in early hominins?
Evidence supporting bipedalism includes the structure of the pelvis, femur, and foot bones, as well as the position of the foramen magnum.
Discuss a major ethical concern related to genetic modification in humans.
A major ethical concern related to genetic modification in humans includes the potential for unintended consequences, such as genetic inequality or the alteration of human traits.
Explain the concept of genetic drift and its impact on allele frequency.
Genetic drift is a random change in allele frequencies, especially in small populations, that can lead to the loss of alleles and reduced genetic diversity.
What role does reproductive isolation play in speciation?
Reproductive isolation prevents different species from interbreeding, which is crucial for maintaining species boundaries and allowing for speciation to occur.
What is the significance of homologous structures in understanding evolutionary relationships?
Homologous structures indicate shared ancestry; their similarities suggest evolutionary relationships between species, despite possible differences in function.
Describe the significance of the "Out of Africa" theory in human evolution.
The "Out of Africa" theory posits that modern humans originated in Africa and migrated to populate other continents, replacing local hominin populations.
How do bioethical considerations influence research on human cloning?
Bioethical considerations in human cloning involve issues of identity, consent, the potential for exploitation, and the implications of creating genetically identical individuals.
How does gene flow affect allele frequencies between populations?
Gene flow is the transfer of alleles between populations through migration, which can increase genetic diversity and alter allele frequencies in both source and recipient populations.
Describe how hybridisation can lead to speciation.
Hybridisation can lead to speciation when hybrids possess traits that allow them to exploit different niches or environments, leading to reproductive isolation from parent species.
Explain the difference between convergent and divergent evolution.
Convergent evolution occurs when unrelated species evolve similar traits due to similar environmental pressures, while divergent evolution involves related species evolving different traits.
Explain the relationship between brain size and the evolution of hominins.
The relationship between brain size and the evolution of hominins indicates that larger brains are associated with increased intelligence, social behavior, and problem-solving capabilities.
Explain the ethical implications of using CRISPR technology in gene editing.
The ethical implications of CRISPR technology include concerns about off-target effects, the long-term impact on genetic diversity, and the moral considerations of "designer babies."
Discuss how a population bottleneck can result in a change in allele frequency.
A population bottleneck occurs when a significant percentage of a population is suddenly reduced, leading to a loss of genetic variation and changes in allele frequencies due to the smaller gene pool.
Explain the concept of adaptive radiation and explain an example (e.g. Darwin's finches).
Adaptive radiation is the rapid diversification of a species into a variety of forms to adapt to different environments, such as the diversification of Darwin's finches in the Galápagos Islands - their beaks adapted according to the available food source.
Discuss how molecular data is used to determine relatedness among species.
Molecular data such as DNA sequencing provides insights into genetic similarities and differences, helping to construct phylogenetic trees and determine relatedness.
How does the study of ancient DNA contribute to our understanding of human evolution?
The study of ancient DNA provides insights into human ancestry, migration patterns, and the relationships between modern humans and archaic hominins like Neanderthals.
Discuss the role of bioethics in conservation efforts for endangered species.