Question

How was the process used to construct the tree of life by Carl Woese different from the process used by Jill Banfield?

Answer 1

Answer and Explanation:

• Carl Woese used ribosomal RNA genes to study the evolution of living beings. He used these genes because they are present in all organisms, and they all have the same function. The nucleotide sequences change very little, giving a real evolutive vision. Woese compared ribosomal genes among different living beings. The sharper the sequence variation is among two organisms, the bigger the evolutive divergence is. This divergence drowned in a phylogenetic tree shows three well-differentiated domains: Archea, Bacteria, and Eukarya.

• Jillian Banfield used genes from 16 ribosomal proteins from many different unknown microorganism species. She and her team used metagenomic methods that are the simultaneous analysis of multiple genomes belonging to many organisms in the same sample. These methods allowed detecting different organisms, even when these were neither previously observed nor lab-cultivated. The comparison among these new genomes with many others already known made a place for the construction of a new and more detailed tree of life where many new branches emerged from the three domains.