Chapter 15, Problem 1NS.1QC

Summary Introduction

To determine:

Why the idea of “The tree of life” was so controversial during Darwin’s time.

Introduction:

“The tree of life” links all the living organisms together through the process of evolution. Evolution can be defined as the gradual changes, which occur in the heritable characters of an organism. Evolution can give rise to the variations in the species or can lead to the speciation. Sometimes, even imperfections can result in evolution.

Explanation of Solution

During Darwin’s time, the idea of “the tree of life” was very controversial because genetic basis of gene transmission was unknown at that time. After Mendel’s work in $\text{1900s}$ , people were able to co-related Darwin’s idea of life as a tree. Mendel’s work supported Darwin’s theory that changes in the DNA (deoxyribonucleic acid) can be caused due to environmental influences that leads to mutations and ultimately, leads to evolution.

“The tree of life” claims that all the living organisms had a common ancestor or every living organism is descended from a common ancestor. It was hard for the people to believe this theory as people at that time believed that God created all the living beings and no change could be made to them. Darwin opposed this belief in his book “On the origin of species” and proposed the idea of evolution and natural selection.

Conclusion

Species present on the earth are related to each other. They all are evolved from a common ancestor. The process of evolution is very hard to notice as it takes place over thousands of years.