In this case, the most suitable experimental design for Marcus to test his hypothesis would be option d.
Option d involves evaluating the amount of grassland in a one-acre section of protected grassland over two years. Marcus will use field cameras to survey the number of prairie dogs and coyotes, and computer software to evaluate the amount of runoff.
The data that Marcus would record for this experiment would include:
1. The amount of grassland in the one-acre section of protected grassland, measured at regular intervals over the two-year period.
2. The number of prairie dogs and coyotes observed using the field cameras, also measured at regular intervals over the two-year period.
3. The amount of runoff, measured using computer software, at regular intervals over the two-year period.
If the observations show that the amount of grassland decreases, the numbers of prairie dogs and coyotes also decrease, and runoff increases in the area, then it would support Marcus's hypothesis that the environmental changes (increasing temperatures and decreasing precipitation) affect biodiversity in the grassland ecosystem.
Marcus is studying Midwestern grasslands. He observed that average yearly temperatures have been increasing and average yearly precipitation has been decreasing; he hypothesizes that these environmental changes might affect biodiversity. What experimental design might Marcus use to test his hypothesis and what data might he record?
a
Over two months, Marcus will evaluate the amount of grassland in a one-acre section of protected grassland and a one-acre section of deciduous forest. Using small-area estimation, he will survey the number of crickets and mice, and he will use GIS software data to evaluate the amount of pollution in the region. Observations that the amount of grassland decreases and the amount of deciduous forest increases; the numbers of crickets decreases; the numbers of mice increases; and there is more pollution in the grassland ecosystem would support his hypothesis.
b
Over two months, Marcus will evaluate the amount of grassland in a one-acre section of grassland surrounded by urban development. Using field cameras, he will survey the number of antelope and prairie dogs, and he will use computer software to evaluate the amount of runoff. Observations that the amount of grassland decreases; the numbers of antelope decrease; the numbers of prairie dogs increase; and runoff decreases in the area would support his hypothesis.
c
Over two years, Marcus will evaluate the amount of grassland in a one-acre section of protected grassland and an area of desert. Using field cameras, he will survey the number of mice and snakes, and he will use computer software to evaluate the amount of runoff. Observations that the amount of grassland decreases and the amount of desert increases; the numbers of mice decrease; the snakes increase; and runoff increases in the desert area and in the grassland area would support his hypothesis.
d
Over two years, Marcus will evaluate the amount of grassland in a one-acre section of protected grassland. Using field cameras, he will survey the number of prairie dogs and coyotes, and he will use computer software to evaluate the amount of runoff. Observations that the amount of grassland decreases; the numbers of prairie dogs and coyotes also decrease; and runoff increases in the area would support his hypothesis.
1 answer