Download rob.evolution_lab_report

Running Head: EVOLUTION LAB REPORT
1
Introduction
Evolution refers to the process by which organisms develop from simple forms to
complex forms. According to Darwin, a trait must satisfy three conditions to evolve through
natural selection. The organism's trait of focus in this report is beak size. Having ascertained that
it affects the survivorship of organisms, it is imperative to determine its variations and
heritability of the variations. This is a lab report that seeks to analyze the variation in beak sizes
among finches. It also examines the heritability in the beak size of these birds. If the beak size
varies among individual bird species, then the trait can evolve through natural selection.
Similarly, if the variation in beak sizes is inheritable, then it can evolve through natural selection.
Experimental Design.
Two experiments were conducted to verify the variation and heritability of beak sizes among
Finches. The experiments were carried out in two islands, Darwin Island and Wallace Island. For
each experiment, Darwin island acted as a control setup while Wallace Island acted as a
treatment. The factors varied for each experiment included population, precipitation and the size
of the Islands. The input value of the first experiment was variation among beak sizes in Finches.
On the other hand, the input value of the second experiment was heritability of variation of beak
sizes in finches.
Experiment 1
Control- Darwin Island
EVOLUTION LAB REPORT
2
Treatment- Wallace Island.
Varying factors- precipitation, population and size of the Islands
Input value- Variation in beak sizes.
Experiment 2
Control- Darwin Island.
Treatment- Wallace Island.
Varying factors- precipitation, population and size of the Island.
Input value- Heritability of variation in beak sizes of finches.
Results
Experiment 1
EVOLUTION LAB REPORT
3
Fig. 1
It shows the results of the first experiment. Darwin Island which acts as the control setup has got
birds with the same size of beaks. Conversely, Wallace Island, experimental setup, has got birds
with varying beak sizes.
EVOLUTION LAB REPORT
Fig 2.
It shows the average beak size of the birds over time for the two islands. The average beak size
for Wallace Island varies while that of Darwin Island is constant.
4
EVOLUTION LAB REPORT
5
Fig.3
The figure portrays the Finch population over time in the two Islands. Finch population in
Wallace island varies at an increasing rate. On the other hand, Finch population in Darwin island
varied at a constant rate.
Experiment 2
EVOLUTION LAB REPORT
Fig.1
It shows heritability of the variable traits in both Darwin Island and Wallace Island. The
heritability in Darwin Island is 0 while that in Wallace Island is 1.
6
EVOLUTION LAB REPORT
Fig. 2
Shows the average beak size of the birds in both Darwin and Wallace Islands. The variable
average beak size of the birds in Wallace Island has been inherited. Similarly, the constant
average beak size of Darwin Island has been inherited.
7
EVOLUTION LAB REPORT
8
Fig.3
The figure shows the inheritance in flinch population in Darwin and Wallace Islands. The
variable and increasing flinch population in Wallace Island has been inherited. Likewise, the
varying yet constant population of flinch in Darwin Island has been inherited.
Discussion and Conclusions.
The results above indicate variation in beak size of finches in Wallace Island which acted as
treatment setup. On the other hand, it shows the constant beak size of finches living in Darwin
Island. Similarly, results show hereditability of the variation of beak sizes in Wallace Island. It is
EVOLUTION LAB REPORT
also evident that these results support the hypotheses. Therefore, it is crystal clear that beak size
evolves through natural selection.
9