Lab for biology
How is an ecomorph different from a species?
An ecomorph is different from a species because it only classifies the organism as having similar body types and habitats, however species have other different characteristics such as color or look.
What is convergent evolution? Use evidence from the trees to explain how the Anolis lizards are an example of this concept.
Convergent evolution is where organisms that aren't closely related, independently evolve and have similar traits due to similar environments or ecological niches. The phylogenetic trees show this type of evolution because similar traits are based on environments, and not location/species type. For example, anolis cybotes and anolis sagrei both are trunk ground anoles, but live on different islands.
What is an ecomorph? Provide one example from the virtual lab.
Ecomorphs are species with similar body types and habitats. "eco" stands for ecological niche and "morph" for morphology, or shape. An example is how the sheplani Hispaniola and occultus Puerto Rico lizards both have short legs, but with slight
In module 1, you identified which species of lizards were most similar to one another based on relative limb length and toe pad size. In this module, you determined which lizards are more similar to one another based on what type of information?
I determined which lizards are more similar based on DNA sequence analysis.
In Dr. Losos's experiment, why was it important that the experimental islands lacked lizards?
It was important because it allowed each ecomorph to be isolated and easier to study their evolutions.
Provide one evolutionary explanation for why lizards living in the same part of the habitat (i.e.,grass) would have similar characteristics.
Lizards in the same habitat would have similar characteristics because there are many ways to do something, however there is only one way that is the best for surviving. Basically, lizards in the same habitat have the characteristics that are most fit for survival, so most lizards in that habitat would exhibit those most fit characteristics.
An adaptation is a structure or function that is common in a population because it enhances the ability to survive and reproduce in a particular environment. Provide one example and an explanation of one adaptation in the Anolis lizards.
One adaptation is the short legs on the sheplani hispaniola anolis lizard. This is most likely due to the slim branch it lives on. The short legs make the lizard able to hold onto the branch/twig better and survive longer because it does not fall off.
Explain how a particular body feature of one of the lizard ecomorphs from the virtual lab is an adaptation to their particular niche.
One of the lizard ecomorphs, the occultus Puerto Rico anole has short legs because it needs to be able to stick to/crawl on slim twigs in their habitat.
The anoles separate and inhabit separate areas of their environment similar to the way the warblers divided up sections of the tree based on where the organisms will survive best.
Resource partitioning makes it easier for species to coexist because there is little to no competition between the species when they are divided so all organisms have their own separate resources that don't need to be shared.
Anolis cristatellus and A. cooki are both trunk-ground anoles that live on Puerto Rico. A.cristatellus lives in a shady, forest environment, while A. cooki lives in an open, sunnyenvironment. What is an adaptive explanation for why the dewlap of one species evolved to be brighter and that of another species darker?
The A. cristatellus has a brighter dewlap and the A. cooki has a darker dewlap. Their dewlap contrasts the brightness of their environment, most likely because it stands out more and attracts more female anoles.
From the bar graph generated in the virtual lab (see below), how do the dewlap colors of the two species compare?
The A. cristatellus has a brighter dewlap by +2.3 and the A. cooki has a darker dewlap by -2.3.
To minimize inter specific competition, organisms often divide the limited available resources in an area, a concept called "resource partitioning." As an example of this concept, the figure below illustrates how different species of warblers utilize different portions of an individual tree.
The anoles display resource partitioning because each species is separated into several different niches based on their body characteristics. For example, the longer legged anoles were on the ground because their long legs make it easier for the anoles to navigate the ground and large trunks.
Explain how the different species of anoles on an island demonstrate "resource partitioning" similar to the warblers in the figure.
The anoles separate and inhabit separate areas of their environment similar to the way the warblers divided up sections of the tree based on where the organisms will survive best.
Based on what you know about the experimental islands and the lizards that were placed on these islands, explain how and why the average leg length of the population might change overtime. Include the concept of natural selection in your discussion.
The average leg length of the population will shrink because of the environment/ecological niches of the experimental island. Because the advantage of longer legs has been lost, some of the anoles will evolve with shorter legs, and some will not. The ones with shorter legs will survive better and the ones with longer legs will survive worse/die off. Therefore, in the end anoles with shorter legs will dominate the population. This process is called natural selection.
What conclusion can you draw about the evolution of the Anolis lizards based on these figures?
The conclusion I can draw about the evolution of the Anolis lizards is based on ecological niches on an island rather than the entire island itself. Two anoles on different islands can have similar traits as long as their ecological niches are similar.
Dr. Losos's data suggest that after only a few generations, the lizards on the experimental islands have shorter legs on average than the lizards on the larger island. Explain how the data you collected either supports or does not support this claim.
The data I collected supported Dr. Losos' claim by showing that because the environment on the island was more suited for shorter legs, the lizards evolved to have shorter legs. Eco-morphs are based on ancestral causes, not geological location/isolation, so the anoles evolved with shorter legs because shorter legs increased their chances of survival.
If a species of anoles with dark dewlaps colonized a heavily forested island, predict what would happen over time to the color of the dewlap. Using your knowledge of natural selection and genetics, explain your prediction.
The dewlaps would eventually begin to become lighter shades due to natural selection in finding a mate.
If the population from one of the experimental islands were reintroduced on the original island,do you predict that lizards from the two populations would still mate and reproduce? Justify your answer with scientific arguments.
The lizards from the two populations, both short legged and long legged will still mate and reproduce because the lizards are still of the same species and because it will increase their species chances of survival.
Are the species of lizard that are more similar to one another according to body type also more closely related based on the results obtained in this module?
The species that are similar according to body type are not more closely related based on the results obtained from the DNA sequence analysis. This is because similar body types are farther away from each other on the phylogeny tree.
How would you determine whether the difference between the two populations is statistically significant?
There is a difference because their bars in the graph have different lengths.
At the beginning of the virtual lab, you were asked to sort eight lizards into categories. What criteria did you initially use to make your groups? Did you revise your criteria later? Why?
We used their colors to identify similar traits between the lizards. Later we realized the legs of two lizards were noticably longer than most, so we grouped those lizards together. We chose not to revise them later because we agreed with our initial groupings.
