Sample Lab Report 2 - PDF

Introduction
Sample Lab Report
#2
Color preferences of Honeybees
Honeybees use both nectar and pollen from flowers as food resources. While collecting
these resources, honeybees also serve as pollinators for many plant species by carrying pollen
from one flower to another. We were interested in the different factors that may affect which
flowers a bee visits, and which flowers it ignores. One of these factors may be the color of the
flower. The purpose of our experiment was to test flower color preference in honeybees.
Color is what an animal’s eye perceives when light is reflected off an object. Light exists
in different wavelengths, and each wavelength is perceived as a different color. Insects and
human eyes cannot see the same range of wavelengths (i.e. they don’t perceive all of the same
colors). Honeybees are not able to see red or orange, but they can see yellow, green, blue, violet,
and ultraviolet (Pollination Partnerships 2002). Ultraviolet is also known as UV light, which
humans cannot see. Given this information, we predicted that honeybees would show no interest
in red flowers, and they would be attracted to yellow and purple flowers.
Methods
To test our hypothesis, we designed an experiment using paper flowers with strawberry
jam on them. We used a flower template in a basic, round-petal shape to trace and cut 16
flowers from sheets of construction paper (Figure 1). We made 4 red, 4 yellow, 4 purple, and 4
white flowers. The flower diameter was 6 inches. We then glued a cap from a 2 L soda bottle to
the center of each flower. In each bottle cap, we smeared 1 teaspoon of strawberry jam.
Figure 1. Flower
pattern (scaled down
version)
We attached each flower to a popsicle stick, using glue, and placed the flowers in the
ground around a honeybee hive. The closest flower was approximately 5 feet away from the
hive, and the farthest was about 10 feet away from the hive. We were careful to place some
flowers on each side of the hive (north, south, east, west).
We observed how many times bees visited each flower color. We did not record the
number of visits to each individual flower, but counted visits to each color group in total. Data
were recorded for two hours following flower placement. Eight students recorded data, each
student being responsible for watching two flowers. A bee had to land on the flower for it to be

considered a visit to that flower. If a bee landed on the paper flower without touching the bottle
cap, we still counted it as a visit.
Our independent variable was the flower color. The control in this experiment was the
white flower group, as white represents light of all wavelengths together. Our dependent
variable was the number of visits each color group received.
Results
Our results show that the white flowers received the most visits, with red a close second.
The yellow flowers received the least visits (Table 1; Figure 2). There is no clear pattern or
trend seen in Figure 2.
Figure 2.
Number of Visits
Table 1. Number of visits to each color.
Color Number of Visits
White 25
Red 24
Yellow 18
Purple 20
30
25
20
15
10
5
0
Number of visits to each color
White Red Yellow Purple
Color

Discussion
Our results did not support our hypothesis that honeybees would prefer yellow and purple
flowers over red flowers. The number of visits for each color, including the control, were fairly
similar. It is possible that color is not the most important factor in flower attraction. Honeybees
may use chemical cues (i.e. smell) to locate nectar and pollen. Since the same strawberry jam
was on each of our paper flowers, maybe the bees were equally attracted to all of our flowers. It
is also possible that the construction paper we used does not reflect light at the same intensity, to
a bee’s eye, as real flower petals. Also, we may have placed the flowers too close together,
creating a food patch that made it too easy for a bee to “jump” from one flower to the next. The
bee could sample all of the flowers with relatively little effort, so perhaps this overrode any color
preferences. It would be a good idea to carry out a similar study watching honeybees in natural
flower patches. We may have manipulated too many variables at one time in our experiment.
References
Pollination Partnerships. 2002. Plants and Pollinators: Exploring Adaptations. Fort Worth:
Botanical Research Institute of Texas. 10 pp.