Question

Pea aphids, Acyrthosiphon pisum, are small, wingless, sap‑sucking insects that live on plants. They evade predators (such as ladybugs) by dropping off of the plants. A study examined the mechanism of aphid drops. Researchers placed aphids on a leaf positioned at four different heights (in centimeters, cm) above a surface covered with petroleum jelly. When a ladybug was introduced, the aphids dropped, and the petroleum jelly helped capture their landing posture (upright or not). Each aphid performed this experiment only once.

Calculate the percentage of aphids that land upright when dropped from the indicated heights. (Enter your answers rounded to one decimal place.)

dropped from 33 cm:

%

dropped from 55 cm:

%

dropped from 10 cm:

%

dropped from 20 cm:

Landing Posture	Dropping Height
	33 cm	55 cm	1010 cm	2020 cm
Upright	1919	2323	2828	3030
Not upright	1212	88	33	11
Sample Size	3131	3131	3131	3131

Answer 1

The percentage of aphids that land upright when dropped from 33 cm

The percentage of aphids that land upright when dropped from 55 cm

The percentage of aphids that land upright when dropped from 10 cm

The percentage of aphids that land upright when dropped from 20 cm