Peace Kiponda
Lab 3 Report
Methods
The primary goal of the study was to investigate the morphological adaptations of anole lizards to
different environmental conditions, specifically focusing on the variation in hindlimb lengths as a
response to their relocation among Caribbean islands. To achieve this, a comprehensive experiment was
designed involving the capture, relocation, and subsequent measurement of anole lizards. Initially, lizards
were carefully captured from their native tree filled habitat on Iron Cay. Following their capture, these
lizards were transplanted to another island, with just bushes, that previously did not host any anole lizard
population. Two lizards, a male and a female, were placed in each island and each year for the next 4
years, data was collected on the newborn species’ hindlimb and body length. This transplantation aimed
to observe the evolutionary adaptations that occur when lizards are introduced to a new environment with
different ecological pressures.
For data collection, both the hindlimb and body lengths of 10 lizards on Iron Cay (control group) were
measured. In addition, 10 more lizards were captured from Iron Cay and placed in Experimental Islands
where same measurements were taken each year for the next 4 years. Measurements were meticulously
taken using software provided by the hhmi BioInteractive, which allowed for precise measurement of Xrays of the lizards, ensuring accuracy and consistency across all data collected. The software facilitated
the measurement of the lizards in millimeters, and the study involved a comprehensive sample size,
measuring a total of n = 20 lizards across both populations.
Data analysis was focused on comparing the relative hindlimb lengths between the original population on
Iron Cay and the transplanted population on the experimental island. The relative hindlimb length was
calculated by dividing the hindlimb length by the body length for each lizard, providing a standardized
metric for comparison. This calculation was essential to understanding the physical adaptations of the
lizards in relation to their environments. Averages of these relative hindlimb lengths were then computed
for both populations. Visualization of the data was achieved through the creation of a bar graph using
Excel, which displayed the average relative hindlimb lengths of the two lizard populations, facilitating a
clear comparison between them.
Results
The study revealed a notable trend in the adaptation of anole lizards to their environments, as evidenced
by the differences in average relative hindlimb lengths between the original population from Iron Cay and
the Experimental Island. Specifically, 0.84 for Iron Cay and 0.8 for Experimental Island were observed,
indicating a significant variation in hindlimb lengths that aligns with the study's hypothesis on
environmental adaptation. Figure 1 below illustrates these findings, showcasing the comparative average
relative hindlimb lengths of the two populations.
Avarage Relative Hindlimb Length
0,85
0,84
0,83
0,82
0,81
0,8
0,79
Iron Cay
Experimental Island
Island
Figure 1: Average Relative Hindlimb Length for Anoles lizards (n = 10) from
Iron Cay and Experimental Island populations after 4 years.
Discussion
The objective of this study was to explore the evolutionary adaptations of anole lizards' hindlimb lengths
in response to their relocation among Caribbean islands, driven by the hypothesis that environmental
changes prompt morphological adaptations. The results, indicating variations in average relative hindlimb
lengths between the original and transplanted lizard populations, suggest significant morphological
adaptations. These adaptations represent an evolutionary response to the differing ecological pressures
encountered by the lizards in their new environment, highlighting the role of fitness and adaptation over
multiple generations.
The observed differences in hindlimb lengths underscore the concept of natural selection, where physical
traits that enhance an organism's fitness in its environment are favored and become more prevalent over
time. This adaptation likely provided the lizards on the experimental island with a morphological
advantage suited to their new habitat, supporting the alternative hypothesis that environmental changes
lead to observable morphological adaptations in anole lizards.
In conclusion, the data from this study support the alternative hypothesis, demonstrating that anole lizards
undergo significant morphological changes in response to their environments. These findings contribute
to our understanding of evolutionary processes, emphasizing the importance of adaptation and fitness in
the survival and reproductive success of species across generations.
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Fix graph.
Mentioned the Trunk ground anoles
Talk about capture process.
More active voice
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State predication and null hypothesis.