A BYU biologist advocates the use of computer analysis to complete a "Tree of Life" model of all species.

PROVO — Falling leaves from the "Tree of Life" are creating a challenge for biologists trying to fill in the genetic characteristics of the world's life forms — including humans — as they seek to find links that could lead to cures for diseases and other benefits for the world at large.

Keith Crandall, a professor at Brigham Young University, is among those who hope their work will someday find a hidden link between creatures that could lead to a cure for cancer.

The BYU biologist has already attracted attention in that quest. Friday will mark the second time an article he has written will appear in the prestigious magazine Science. The article is an assessment of advances made in the field of biological systematics, the study of how earth's organisms are connected.

"It's basically organismal genealogy," Crandall said. "That's what we're doing, finding out how all of these plants and organisms are related to each other."

Crandall's article provides a perspective on using super computers to find information that connects all living organisms into one great "Tree of Life." Scientists across the world study aspects of the "Tree of Life" and submit genetic codes into a giant database, Gen Bank, which is accessible on the Web.

Biologists seeking to completely characterize the genetics of a certain species can go to the database to get information that will hopefully help fill in blanks in their research. The process makes it possible to develop a probable picture of the "Tree of Life" that connects bacteria, humans, and all living things, even though the information is spotty and incomplete.

"Intuitively you would think that if you're missing a lot of information you could only have a sketchy view of what's going on," said Michael Whiting, a colleague of Crandall, who teaches biology at BYU and also studies the "Tree of Life."

"But other people think all you need is sketchy information, and from that, you can derive a very interesting picture of organismal evolution," Whiting said.

The ability to use the database to create a probable picture of the "Tree of Life" is something that encourages Whiting and Crandall. Whiting said powerful things can be done with the data already collected, even with the limitations imposed on completing many of vast number of genetic characterizations.

The impacts from the work being done on the "Tree of Life" range from being able to better determine areas in need of conservation efforts to finding cures for diseases that are genetically linked within species in the system.

The biggest problem facing biologists working on the project, according to Crandall and Whiting, is completing work while facing the ongoing and rapid extinction of many species. Whiting said valuable information is being lost because the rate of extinction is outpacing the ability of biologists to complete characterizations for many species.

"If you can get these deep relationships by exploring these computational aspects, you could get more information on those leaves (of the 'Tree of Life'), which are dropping," Crandall said. "Species are going extinct at a very high rate. If we don't get out there and identify a lot of these species soon, we're going to miss a lot of them."

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