Sample Geology Case Study Paper on Speciation Lab Report

Speciation Lab Report

Time progression of speciation

            Please click on the link to view the time progression of speciation of lizards


            The objective of this study is to find out what would happen if lizards belonging to a specific species were suddenly split into two main groups as a result of a hurricane.


            Over the past, erudite Scientists had come up with a myriad of different definitions on what species are. The term species has been collectively elucidated as a group of organisms that can naturally interbreed to produce viable offspring’s.  However according to a series of carried out research studies, organisms belonging to the same species have been found to possess the ability of giving rise to two or more different distinct species (Howard, 1998). It is with such results that the term speciation of species was conceptualized to describe the occurrence of two or more species as a result of being offspring of a single population of species. These two species are however incapable of interbreeding and for that matter, they are unable to give rise to their own generation. Furthermore, the two or more species may evolve with time into distinct and separate species. One of the ways by which speciation arises is due to geographic separation (Duffy, 1996). This gives rise to the allopatric speciation. This kind of speciation generally occurs when the individual of a single species gets separated from one another by geographic barriers (Howard, 1998).

Hypothesis/predicted outcome

The population of lizards found in mainland is distinct and cannot interbreed with the small group of lizards found on the island.


            In order to access if the lizard species found on mainland are different from the small group of individual lizards found on the island, the following techniques were used;

  • Collection of live lizard samples representing each geographic location; those from the island and those from the mainland
  • Carrying out morphological analysis through observing the unique morphological physical traits of each lizard
  • Collecting data with regard to the behavior of each of the lizards belonging to different geographical localities
  • Carrying out genetic analysis to ascertain that the two groups of lizards are genetically distinct. This would give a clear assurance as to whether different geographic localities act as a factor in separating a single species of organism into two or more distinct organisms.
  • Carrying out an analysis of data


            The two different groups of lizards differ from each other in terms of their morphological characteristics, behavioral and their genetic makeup. In terms of their morphology, the groups of lizards that are from the mainland were quite larger in terms as body size as compared to the lizards that are from the island. Besides this, lizards from the mainland had a dark brown complexion of body color as compared to those found on the islands which were of a lighter version. The tails of lizards belonging to the mainland locality were longer as compared to the lizards from the upstream. One of the behavioral traits that made the two groups to be distinct was the fact concerning reproduction. The two different groups of lizards could not interbreed with each other. However, when the two groups of lizards were separated, they were able to mate among themselves to produce offspring of the same kind.

            In conclusion, the two different groups of lizards were found out to be genetically distinct. This was after a series of PCR and DNA sequencing. This led to the affirmation that indeed the two groups of lizards belonged to two different species.


  • The lizards from the island were of a lighter shade as compared to those on the inland due to the differences in climatic conditions affecting the different geographic zones.
  • The lizards from the mainland could not interbreed with those from the mainland. This indicated that the lizards were of two different species and thus their inability to interbreed and produce viable offspring.
  • The lizards from the two localities had behavioral differences. This was as a result of the lizards adapting to their respective environs and thus the development of certain behaviors that matched with the environment.
  • The lizards living on the island had a smaller body size as compared to those living on the mainland. The small body size means that the lizard has a larger surface area to volume ratio. This thus functions in increasing the metabolism rate. Lizards from the island thus had a higher rate of metabolism as compared to those from the mainland.
  • As a result of the geographical barrier that separated the single species of lizard, the lizards on the island had to adapt to the new environment and develop certain features that made them to be distinct from the others on the mainland.
  • This outcome is as expected due to the fact that organisms of the same species become genetically different when separated by geographical barriers for an extensive period of time. Thus, variables such as different geographical locations and that of time are important in causing allopatric selection among organisms of the same species.
  • Overtime, evolution of different groups of species has occurred due to what scientists explain as natural selection. However, besides natural selection, the development of geographic barrier that separates population of the same species has led to an increase in biodiversity of the once single species.
  • This has led to allopatric speciation, as the population of a single species diverges to different groups of organisms that are genetically distinct and can no longer interbreed (Camargo et al., 2010).


Camargo, A., Sinervo, B., & Sites, J. W. (2010). Lizards as model organisms for linking phylogeographic and speciation studies. Molecular Ecology, 19(16), 3250-3270.

Duffy, J. E. (1996). Species boundaries, specialization, and the radiation of sponge‐dwelling alpheid shrimp. Biological Journal of the Linnean Society, 58(3), 307-324.

Howard, D. J. (1998). Endless forms: Species and speciation. New York [u.a.: Oxford Univ. Press. Howard, D. J. (1998). Endless forms: Species and speciation. New York [u.a.: Oxford Univ. Press.