Animal Diversity Rats and Cats Paper

Question 1

Toxoplasma gondii’s manipulation appears to alter rats’ perception of … … …, in some cases turning their innate aversion into an imprudent …

Answer 1

cat predation risk

attraction

Question 2

The selectivity of such behavioural changes suggests that this ubiquitous parasite subtly alters the … of its … host to enhance … rate whilst leaving other behavioural categories and general health intact

Answer 2

brain, intermediate, predation

• in contrast to the gross impediments frequently characteristic of many other host-parasite systems

Question 3

According to the manipulation hypothesis, a parasite
may alter the behaviour of its host for its own benefit,
usually by enhancing its … …

Answer 3

transmission rate

Question 4

T. gondii is capable of infecting all…

Answer 4

mammals

Question 5

Members of the cat family are the … hosts
of the parasites and the only mammals known to shed
T. gondii … with their …

Answer 5

definitive, oocysts, faeces

Question 6

… are the intermediate hosts.

Answer 6

Rodents (e.g. rats)

- thin-walled cysts form in various tissues, most commonly the brain - remain viable for life of host

Question 7

A cat can become infected by either of two routes: it may … … oocysts shed from another cat in the environment, or it may ingest cysts when eating infected … … …

Answer 7

Directly ingest,

intermediate host prey

Question 8

There is a mean prevalence of … of the rat population being infected by the parasite

Answer 8

35%

Question 9

T. gondii causes an increase in … and a decrease in … (fear of novelty) behaviour

Answer 9

activity, neophobic

Question 10

Other costly behavioural patterns in rats such as competition for mates and social status, which do not have any obvious impact upon cat … …, are … … by the parasite

Answer 10

predation rate, left un-altered

Question 11

Uninfected rats have evolved to avoid predators such as cats. Even … laboratory rats that have not been in contact with cats for several hundred generations still show strong … … when confronted with cat …

Answer 11

naive, aversive reactions, odours

Question 12

The Lister-hooded laboratory strain of rat was chosen because of its reported…

Answer 12

behavioural similarity to wild rats

Question 13

The final sample size for analysis consisted of

… infected rats and … uninfected rats

Answer 13

23, 32

Question 14

What were the four corner smells?

Answer 14

Rat’s own smell (straw bedding), neutral (water), undiluted cat’s urine, undiluted rabbit urine (Served as control for mammalian non-predator)

Question 15

Each of the scented areas also contained a … and

… bowl covered by a transparent plastic cover

Answer 15

water, food

Question 16

Infected individuals (rats) show no difference from uninfected individuals in terms of … … …, and behavioural changes unlikely to influence … …

Answer 16

general health status, predation rate

Question 17

Infected rats behaved similarly with respect to areas containing their own smell (which was preferred by both), neutral smell and rabbit odour. This suggests that the potentially … attraction exhibited by infected rats was not caused by a gross … of … faculties.

Answer 17

fatal, impairment, olfactory