Tuesday, 1/28
➢ Parasite-living organism that lives in an intimate and durable relationship with a host that
suffers a fitness cost
➢ Mosquito quickly taking blood does not count as a parasite
➢ “Fitness cost” is context-specific
➢ Ectoparasites live on outside of host(ticks, lice)
➢ Endoparasites live inside host(tapeworm)
Parasite or not?
→ Mosquito-no
→ Bed bugs-no
→ Human roundworms-yes
➢ 40% of species estimated to be parasites(60% non-parasites)
➢ Parasitism has evolved 233 times in 15 phyla
➢ 4 groups-Platyhelminthes(flukes, tapeworms), nematoda(roundworms, pinworms, filarial
worms), arthropods(insects, mites, crustaceans), and protozoa(amoebae, flagellates,
ciliates, apicomplexans)
➢ Hookworms, whipworms, etc. Tend to infect the most people
➢ 342 species of parasite worms found in humans
How to succeed
➢ Come to class
➢ Take and review notes
➢ Turn in every assignment
➢ Come to office hours
➢ Use STEM Center
➢ Study together
Words/Vocab to Know
➢ Darwinian “fitness”-reproductive output, survival(all about the offspring)
➢ Symbionts- “living together”, the “intimate and durable” part
→ Not every symbiont is a parasite
➢ Mutualism-both species benefit(example: sea anemone and clown fish)
➢ Commensalism-one benefits, one is unaffected(barnacle and a whale)
, ➢ Parasitism-one benefits, one is harmed(tick and a dog)
Which relationship?
➢ Bat and a bat fly-parasitism
➢ Flower and a bee-mutualism
➢ Bull and bird-commensalism
Thursday, 1/30
➢ Important Terms from last class
➢ Prevalence-number of affected people in a population by a parasite
➢ Trophic relationships-parasite eating host or taking food from host; parasites can be
passed in food
➢ Incidence-how frequently parasitism occurs in a time period; differs from prevalence as
prevalence is a snapshot
➢ Complex life cycle-two or more hosts required to maintain fitness
➢ Simple life cycle-only one host is infected
→ Some parasites have both simple and complex life cycles
➢ Abundance-number of parasites living on or in a host
➢ Zoonosis-disease transmitted from animals to humans(example: rabies); transmitted
through direct or indirect contact, inhalation, etc.
➢ Epidemic-sudden disease outbreak that spreads rapidly and affects a large
population(humans)
➢ Epizootic-same as an epidemic, but for an animal population
➢ Macro parasites-large organisms that lead to long-lasting infections
➢ Microparasite-smaller than can be seen with the human eye
➢ Sylvatic-involves nonhuman animal hosts or woodland creatures and insects
➢ Reservoir host-serves to amplify a parasite(raccoon, bat), can take in host without
becoming sick
➢ Intermediate host-provides place for parasite; parasite develops but cannot reach full
sexual maturity
➢ Definitive host-parasite can reproduce
➢ Vector-permanent or temporary host, will transmit parasite from host to host
➢ Host specificity-degree of restriction for a parasite and who/what it infects
➢ Active transmission-parasite finds host(tick waiting for a human)
→ In passive transmission, parasite does less work
➢ Aggregation-high concentration of parasites in a small number of hosts
➢ Paratenic host-parasite that does not develop, but can use this to reach another host
➢ Parasite-living organism that lives in an intimate and durable relationship with a host that
suffers a fitness cost
➢ Mosquito quickly taking blood does not count as a parasite
➢ “Fitness cost” is context-specific
➢ Ectoparasites live on outside of host(ticks, lice)
➢ Endoparasites live inside host(tapeworm)
Parasite or not?
→ Mosquito-no
→ Bed bugs-no
→ Human roundworms-yes
➢ 40% of species estimated to be parasites(60% non-parasites)
➢ Parasitism has evolved 233 times in 15 phyla
➢ 4 groups-Platyhelminthes(flukes, tapeworms), nematoda(roundworms, pinworms, filarial
worms), arthropods(insects, mites, crustaceans), and protozoa(amoebae, flagellates,
ciliates, apicomplexans)
➢ Hookworms, whipworms, etc. Tend to infect the most people
➢ 342 species of parasite worms found in humans
How to succeed
➢ Come to class
➢ Take and review notes
➢ Turn in every assignment
➢ Come to office hours
➢ Use STEM Center
➢ Study together
Words/Vocab to Know
➢ Darwinian “fitness”-reproductive output, survival(all about the offspring)
➢ Symbionts- “living together”, the “intimate and durable” part
→ Not every symbiont is a parasite
➢ Mutualism-both species benefit(example: sea anemone and clown fish)
➢ Commensalism-one benefits, one is unaffected(barnacle and a whale)
, ➢ Parasitism-one benefits, one is harmed(tick and a dog)
Which relationship?
➢ Bat and a bat fly-parasitism
➢ Flower and a bee-mutualism
➢ Bull and bird-commensalism
Thursday, 1/30
➢ Important Terms from last class
➢ Prevalence-number of affected people in a population by a parasite
➢ Trophic relationships-parasite eating host or taking food from host; parasites can be
passed in food
➢ Incidence-how frequently parasitism occurs in a time period; differs from prevalence as
prevalence is a snapshot
➢ Complex life cycle-two or more hosts required to maintain fitness
➢ Simple life cycle-only one host is infected
→ Some parasites have both simple and complex life cycles
➢ Abundance-number of parasites living on or in a host
➢ Zoonosis-disease transmitted from animals to humans(example: rabies); transmitted
through direct or indirect contact, inhalation, etc.
➢ Epidemic-sudden disease outbreak that spreads rapidly and affects a large
population(humans)
➢ Epizootic-same as an epidemic, but for an animal population
➢ Macro parasites-large organisms that lead to long-lasting infections
➢ Microparasite-smaller than can be seen with the human eye
➢ Sylvatic-involves nonhuman animal hosts or woodland creatures and insects
➢ Reservoir host-serves to amplify a parasite(raccoon, bat), can take in host without
becoming sick
➢ Intermediate host-provides place for parasite; parasite develops but cannot reach full
sexual maturity
➢ Definitive host-parasite can reproduce
➢ Vector-permanent or temporary host, will transmit parasite from host to host
➢ Host specificity-degree of restriction for a parasite and who/what it infects
➢ Active transmission-parasite finds host(tick waiting for a human)
→ In passive transmission, parasite does less work
➢ Aggregation-high concentration of parasites in a small number of hosts
➢ Paratenic host-parasite that does not develop, but can use this to reach another host
