lecture 26

Question 1

2 different levels of consciousness

Answer 1

1. Perceptual (primary): awareness of one’s own sensory perceptions
2. Reflective: awareness of being aware of one’s thoughts; attributing mental states to others

Question 2

Medicine

Answer 2

practice that deals with conflicts, whose main function is to intervene on the side of one of the contenders-the patient

Question 3

Darwinian Medicine

Answer 3

the hunt for evolutionary explanations of why were are susceptible to disease or discomforts

Question 4

Categories of evolutionary explanations for disease

Answer 4

novel environments, design compromises, evolutionary legacies, defenses, infection, genes

Question 5

Novel environments examples

Answer 5

professor that went back in time and was the only one wearing glasses because others didn’t have sight issues associated with close up tasks (reading); human body has only recently adapted to its current environment with lots of high-fat foods; the leading causes of death are now heart disease, cancer, stroke which are different that previous prominent causes of death, these things are killing us because our evolution has not kept up with the rapidly changing environment

Question 6

Design compromises

Answer 6

we have certain trade offs associated with over-designing any one body system that in turn disrupts the functionality of the organism as a whole

Question 7

Evolutionary legacies

Answer 7

ancestral design has stuck around even if it doesn’t optimize functioning; ex. we still use the same tube for eating and breathing even though it can lead to choking, the retina is actually strapped on backwards which causes us to have a blind spot

Question 8

Defenses

Answer 8

Avoidance and repair- when we get injured, the injured region has increased sensitivity which leads us to avoid touching it and allows it to heal better; symptoms such as cough or fever can help get over an infection

Question 9

Smoke-detector principle

Answer 9

having a severe response to something that actually doesn’t pose a real threat is only a minor inconvenience (allergies), but there are far worse consequences for failing to mount a response if there is a real threat- could result in death

Question 10

Infection: evolutionary arms race

Answer 10

Red queen hypothesis; human beings are in constant battle with infectious organisms that are constantly being fine-tuned by evolution

Question 11

Pathogen manipulation

Answer 11

the pathogen manipulates the host’s physiology or behavior to facilitate its spread

Question 12

Adaptive host response

Answer 12

the host responds to infection in a manner that is beneficial to the host, usually to the detriment of the pathogen

Question 13

Example of pathogen manipulation: Shigella enteritis

Answer 13

causes symptoms that include diarrhea and vomiting which allows it to maximize its spread because it spreads to others through toilets/sewers

Question 14

Vector-borne vs. directly transmitted disease

Answer 14

vector-borne diseases are much more likely to bring death to the host; graph shows that infections that have more waterborne outbreaks cause more deaths

Question 15

toxoplasma gondii: example of altered host behavior

Answer 15

infects mice which are just their intermediate host and changes the behavior of the mice to make them less afraid of predators and more likely to venture out into the open; this behavior change increases the chance that infected mice will be consumed by the parasite’s final host, cats; correlation between uncertainty avoidance (less fearful) and higher infection rate; also correlation between masculine sex roles and prevalence of T. gondii-parasite may be making males more masculine to increase mating and spread of disease

Question 16

Rabies virus and host behavior

Answer 16

Rabies infection results in brain inflammation which changes behavior of host, making host more likely to bite another individual and spread the disease to another victim

Question 17

Malaria infection

Answer 17

malaria increases attractiveness of humans to mosquitos, making them more likely to bite and suck the blood of the infected and then facilitating the spread to the others who are bitten by the same mosquito

Question 18

Fever in locusts

Answer 18

locusts that had infection spent more of their time basking in the sun in order to give themselves a fever to better fight the disease

Question 19

Behavioral fever in the desert iguana

Answer 19

they regulate body temp by moving to warmer or cooler locations; iguanas that were injected with dead bacteria chose higher body temps and spent more time in the warmth; another study infected lizards with live bacteria and then manipulated the temperature they were housed at; lizards kept at lower temperatures mostly died while those kept at high temps had high survival rate; suggests fever is adaptive for the iguanas

Question 20

Syphilis and malaria study

Answer 20

syphilis patients that were intentionally infected with malaria showed an increased probability of recovery from syphilis

Question 21

Study: fever and the common cold

Answer 21

adults were intentionally infected with rhinovirus 2 (common cold) and then were treated with over the counter meds; placebo group who didn’t take drugs suffered less stuffiness and made more antibodies to the virus, reducing the fever lowered the body’s ability to fight disease

Question 22

Huntington’s disease

Answer 22

transmitted by an autosomal dominant gene; produces a mutant form of the protein htt, which aggregates in brain causing neurodegeneration; mutation caused by string of trinucleotide repeats; phenotype isn’t normally displayed until late in reproductive window, making it transparent to natural selection

Question 23

The Health Benefit Hypothesis of H.D.

Answer 23

1. Fitness benefit: HD+ individuals have higher fertility levels and will have more offspring
2. Survival benefit: mutant HD allele confers health benefits (lowered incidence of cancer) during asymptomatic periods

Question 24

p53 and htt

Answer 24

htt protein produced by those with H.D. causes upregulation of p53, which is an immune protein involved with destroying damaged cells and vital for prevention of unchecked cellular replication in cancer; better health in HD patients may be associated with more p53 which upregulates immune system