ANTH Final: PART 3 - Disease and Human Evolution

Q: What do we mean by the term “host-pathogen arms race”?
A: The "host-pathogen arms race" refers to the ongoing evolutionary struggle between hosts (like humans) and pathogens (like viruses and bacteria), where each evolves new defenses or attack strategies in response to the other. It's a form of co-evolution.

Q: What are some examples?
A: Examples include the evolution of sickle cell trait in humans as protection against malaria; bacterial resistance to antibiotics like MRSA (methicillin-resistant Staphylococcus aureus); and the rapid mutation of influenza viruses to escape immune detection.

Q: How has the invention and use of antibiotics both given an edge to humans in arms races with bacteria and introduced a new level to these races, with consequences that can be seriously negative for the humans?
A: Antibiotics have saved countless lives by killing or inhibiting bacteria, giving humans a major advantage. However, overuse and misuse have driven bacteria to evolve resistance, creating antibiotic-resistant strains that are harder to treat and pose a serious global health threat.

Q: The term “epidemiological transition” has traditionally been associated with the shift from hunting and gathering to food production has traditionally and, subsequently, with the Industrial Revolution. In general, what factors related to the domestication of plants and animals and to the development of large-scale production of manufactured goods underlay the changes in disease ecology and in host-pathogen arms races that were responsible for these “transitions”?
A: Key factors include increased population density, closer proximity to domesticated animals (leading to zoonotic diseases), sedentary lifestyles, poor sanitation, and pollution. These changes created new environments for disease spread and intensified host-pathogen coevolution. Later industrialization added crowding, poor working conditions, and urbanization, all of which further altered disease patterns and pressures.

Q: What do “emerging infectious diseases” and “re-emerging” ones tell us about the impact of disease as a selective force in human evolution and about whether humans are still subject to natural selection?
A: These diseases show that humans are still evolving in response to pathogens. New diseases (like COVID-19) and the return of old ones (like tuberculosis) highlight how disease remains a powerful selective force and how genetic and immune adaptations continue to shape human populations.

📚 Term Recognition Flashcards

Q: HIV and SIV
A: HIV (Human Immunodeficiency Virus) causes AIDS in humans; it originated from SIV (Simian Immunodeficiency Virus) found in non-human primates, making it a zoonotic disease.

Q: Zoonotic/Zoonoses (know a couple of examples)
A: Zoonotic diseases (zoonoses) are infections that spread from animals to humans. Examples include HIV (from primates), COVID-19 (likely from bats or intermediate hosts), and influenza (from birds or pigs).

Q: Adaptive (acquired) immunity
A: Adaptive immunity is the part of the immune system that develops specific responses to pathogens through exposure, involving memory cells that provide long-term protection.

Q: Antibody
A: An antibody is a protein produced by B cells in response to a specific antigen; it binds to pathogens to neutralize or mark them for destruction.

Q: T-Helper cell
A: A T-helper cell is a type of white blood cell that plays a critical role in the immune system by activating other immune cells, including B cells (to produce antibodies) and cytotoxic T cells.

Q: Emerging infectious disease
A: An emerging infectious disease is a newly identified or previously rare infection that is increasing in incidence or geographic range, such as SARS, MERS, or Ebola.