While adding more data can clarify relationships between organisms and place them on the tree of life, sometimes more data can make the picture look fuzzier. "[J]ust as the spinal column and limbs created contrasting maps of primate evolution, scientists now know that different genes in the same organism can tell different stories," writes Emily Singer at Wired.
Researchers are now turning to algorithms to sort out such phylogenetic relationships, Singer adds. In a recent Nature paper, researchers from Vanderbilt University used a common concatenation approach to build a phylogenetic tree based on 1,070 genes and 23 yeast species and they further built a series of trees based on the genes individually. They then tried to reconcile their trees. However, "none of the 1,070 gene trees agreed with each other, with the concatenation phylogeny or with the [extended majority-rule consensus] phylogeny," the researchers write.
"I am not so sure we know what the true relationships are," Yale University's Michael Donoghue, who was not part of the study, tells Singer. "If we aren't sure what the truth is, we can't tell if we have the right tree."