Brazilian fire ants have recently invaded Texas woodlands and grasslands. Scient
ID: 48591 • Letter: B
Question
Brazilian fire ants have recently invaded Texas woodlands and grasslands. Scientists studied whether the fire ants impacted the structure of native ant communities. They set up pitfall traps to catch ants in sites that were either “infested” with fire ants or “uninfested.” Consider the following figure:
1) What is/are the independent variable(s)?
a) species richness
b) number of ants (abundance)
c) species richness and abundance
d) infestation status and site
2) What is/are the dependent variable(s)?
a) species richness
b) number of ants (abundance)
c) species richness and abundance
d) infestation status and site
3) What do the letters A-E represent?
a) five different ant species
b) five different sites
c) ten different ant species
d) ten different sites
4) What was the maximum observed value for species richness among infested sites?
a) 8
b) 12
c) 18
d) 20
5) What do the observed differences in bar height for species richness represent?
a) site to site variability
b) effects of invasive ants
c) site to site variability and effects of invasive ants
d) cannot be determined
6) What is the main conclusion of this study?
a) invasive ants reduce species richness and number of native ants
b) native ants reduce species richness and number of invasive ants
c) invasive ants are not very abundant relative to native ants
d) invasive and native ants do not appear to interact significantly
7) What statistical test would be most appropriate for evaluating this conclusion?
a) Correlation
b) regression
c) chi-square
d) ANOVA
8) Which of the following is NOT an assumption of this type of analysis?
a) means are equal
b) variances are equal
c) data are normally distributed
d) data are independent
Explanation / Answer
1) d) infestation status and site
2) c) species richness and abundance
3) d) ten different sites
4) a) 8