2. Evolution

Evolution is a cornerstone to learning about biology. It is about life and about change. Life is always changing. Change is occurring to every living thing on earth, but it is not limited to individuals. Evolution is a much more vast concept because it includes populations of every species on earth.

This is my personal reflection and summary of this week's work: This week, I was able to learn about Anole species and how location impacts evolution. This was interesting to see that there could be such a variety of species of Anoles that looked so different all in the same environment with small location changes, like positioning on the tree. Something else that was incredibly interesting was that these species of Anoles could be found in different islands in the Caribbean. Even though they were in different places, they evolved to form similar species. What was even more interesting is that they evolved in different orders, yet still produced the same outcomes of species. This is evidence of evolutionary convergence.
    I also found out this week that only 28% of teachers are teaching about evolution. This number is shocking because it is a huge topic in biology. Evolution needs to be taught to all students so that they can be informed on the ideas of how all the species came to be. There are so many parts of evolution that help to explain why there are so many species in the world. Without this knowledge, students would be uninformed about the science world. It is an important topic that needs to be taught, even if some people don't agree with it.

These Irises show the diversity of life and species. Biodiversity is one of the key elements of evolution and it is also why evolution is so important. These flowers are showing that slight differences can cause major differences and produce very different outcomes. They are showing a very small picture of a much greater idea of the diversification of life.

The following lab is my work: Shelby Johnson

Topic 1: Identifying the Ecomorphs

For each species of Anole, I used the images to determine the ecomorph of each species. I used clues from body shape, color, and habitat.

Species Body Shape Color Habitat Ecomorph

Table 1. My observations of anole characteristics.

Topic 2: Adaptive Radiation and Convergent Evolution

1. In your opinion, what selective factors must be the same (or sufficiently similar) in order for

Anole evolution to converge independently into the same ecomorphs on each of the four

Caribbean islands?

List at least four such factors and write them in your lab notes.

In order for Anole evolution to converge independently into the same ecomorphs there needed to be a lack of predators, similar environments, competition for mates in the same species, and similar favorable traits like color needed to be same.

2. The South American mainland has very different ecological niches than the islands we are

studying. The mainland anoles have very different morphologies than island Anoles. Does this

information support the theory of evolutionary convergence of anole ecomorphs?

Yes it does support the idea of evolutionary convergence because it shows that the environments played a role in the convergence. South America has a different environment, so the Anoles look different in South America compared to the Caribbean. This shows that having similar environments is necessary for evolutionary convergence to occur.

3. What does it say about the requirement for similarity of environmental conditions?

Compare each ecomorph to the next ecomorph to evolve on the tree and record your observations

in your notes. Consider:

1. How close are their ecological niches to each other?

2. What do you think is the evolutionary significance of the location of the ecomorph on the tree? 

3. Repeat the annotations and niche comparison with all four island phylogenetic trees. Observe

which hypothesis is supported by comparing the four phylogenies.

Cuban: Crown Giant, Trunk-Ground, Trunk-Crown, Twig

The Crown Giant isn't close to the Trunk-Ground. Then the Trunk-Ground and Trunk-Crown aren't close either. However, the Trunk-Crown and Twig are closer together. There was a lot of evolutionary jumping going on. This shows that location is evolutionary significant.

Hispaniolan: Trunk-Crown, Twig, Crown Giant, Trunk-Ground.

Trunk-Crown and twig are close. And Crown Giant is close to Twig. However, Crown Giant and Trunk-Ground are pretty far away. The evolutionary branching was close together until the Trunk-Ground. This shows that location is evolutionary significant.

Jamaican: Twig, Trunk-Ground, Crown Giant, Trunk-Crown

Twig and Trunk-Ground aren't close to each other. Then there was a huge jump up to Crown Giant. And then Crown Giant and Trunk-Crown are fairly close. There was major evolutionary jumping going around in these first three branches. This shows that evolutionary location is significant.

Puerto Rican: Twig, Crown Giant, Trunk Ground, Trunk-Crown

Twig and Crown Giant were close. But Crown Giant and Trunk-Ground aren't close. Then Trunk-Ground isn't close to Trunk-Crown. After the first initial branching, the evolution became more sporadic.

The changes in each phylogeny show that ecological location, where the Anoles were on the tree, are important. It is also interesting that none of the islands had the same phylogeny, which is more evidence that location changes evolution. This shows that location and environment are very important and make significant changes in evolution. The hypothesis that is supported by these phylogenies is the theory of one original colonization that later was changed due to adaptive radiation and convergence.