You will respond to your classmates’ posts and add something new. The response is broad this week, but I encourage you to discuss your opinions and thoughts. Science isn’t set in stone. The ‘helpers in the nest’ theory is controversial, even among evolutionary biologists, as are many topics in this category. BUT DON’T FORGET TO CITE THEM.
During the industrial revolution, factories were popping up all over Europe and being solely run by burning coal. These factories created black smoke that coated absolutely everything. All of the beautiful light colored trees were now darkened and bare. [If you have ever seen the lorax, it is highly comparable to what was happening here.] The peppered moth species was notably changing due to this newfound pollution. The white/light colored moths also became dark in color. Scientist tried desperately to figure out why. Was it the smoke, was it the chemicals? They went back and forth with ideas of a similar nature until they realized that the color of the moth was genetic. It turned out to be an evolutionary change. Moths that were being born dark was caused by a mutation in the moth DNA and the mutated gene was being passed to all the offspring.
J. W. Tutt discovered in 1896 that the peppered moths were camouflaging themselves. The light moths were no longer hidden against the darkened trees and stuck out to predators. The darker the moth, the longer they lived and had more time to breed and reproduce. As prey in the forrest they became less noticeable. Since being darker was a favorable trait, it was replicated and passed on to future generations so that more favorable offspring could be produced. The weak and unfavorable trait of being a light colored moth died out. Scientists called this effect industrial melanism. If you remember my post from last week about melanocytes and melanin this term makes sense as melanin has to do with darkened pigments, and it was happening during the industrial revolution. It was found that as countries began working towards reducing pollution, the number of dark moths decreased (as being lighter then became the favorable trait).
Here’s a picture of the moths
“Natural Selection.” Peppered Moths: Natural Selection, Arizona State University, https://askabiologist.asu.edu/peppered-moths-game/natural-selection.html.
Warrior ants and their colonies are an example of an evolutionary change that has made them biologically successful due to their ability to change their chemical communication among colonies for attack to gain resources, detect danger, and keep their own close. Warrior ants can “eavesdrop” on others’ chemical compounds or aromas to trick their prey into believing they are part of the same colony only to come in a take their resources. Amongst their own colonies, they can give off danger pheromones that let their colonies know of danger approaching. When other colonies may come to attack, the warrior ants can sense the difference in chemical compounds that are not of their own and therefore they are able to warn their own colony.
Adams, R. M., Wells, R. L., Yanoviak, S. P., Frost, C. J., & Fox, E. G. (2020). Interspecific eavesdropping on ant chemical communication. Frontiers in Ecology and Evolution, 8. https://doi.org/10.3389/fevo.2020.00024