Natural Selection- Post 1

In Survival of the Sickest, Dr. Sharon Malone connects many conditions to environmental factors. Some diseases are onset by environmental factors and other diseases can combat environmental factors. There is no doubt that the environment plays a large role in the way our genes are expressed and these expressions can vary depending on the condition being observed and the type of environment. In chapter 1 Malone, who has a first hand account of hemochromatosis, focuses on the effect of excess iron in the body. The excess iron can have a positive or negative effect on the body. This supports the fact that mutations are not always bad for you, and in some cases can be beneficial. This relates to Big Idea 1: The process of evolution drives the diversity and unity of life. Mutations can later lead to the evolution of traits that are selected for.
Individuals with hemochromatosis during the Dark Ages when the bubonic plague spread across Europe were more likely to survive. On page 12 Malone states this is because even though people with hemochromatosis experience an excess amount of iron in the blood, iron is depleted from certain cells, more specifically macrophages. These macrophages capture and destroy diseases so when they lack iron the diseases are not able to multiply and grow stronger.
Research and explain a hereditary disease that results from various environmental factors. Is there a mutation involved? Identify whether these mutations pose a threat or could it possibly benefit the individual?
Discuss whether or not these diseases are still around today and if natural selection favors these individuals.
Furthermore, on page 8 Malone connects iron to birds and their eggs. Chelators, which is present in our bodies, also helps prevent chicken embryos from getting infected by warding off iron and increases the embryo's chances of survival. State whether the disease has any effect or is in any way related to another species survival.

Ted Nowak (tnowak4@students.d125.org)