Featured Research

from universities, journals, and other organizations

Digital Organisms Used To Confirm Evolutionary Process

Date:
July 19, 2001
Source:
Michigan State University
Summary:
Using a revolutionary computer program that gives scientists the opportunity to watch evolution take place before their eyes using "digital organisms," a team of researchers from Michigan State University and Caltech has confirmed an evolutionary process long suspected but, until now, unproven.

EAST LANSING, Mich. - Using a revolutionary computer program that gives scientists the opportunity to watch evolution take place before their eyes using "digital organisms," a team of researchers from Michigan State University and Caltech has confirmed an evolutionary process long suspected but, until now, unproven.

In a paper published in the July 19 edition of the journal Nature, MSU researchers Richard Lenski and Charles Ofria, along with colleagues at Caltech, provided some insight into one aspect of Darwin's theory of natural selection that they dubbed "survival of the flattest."

The paper's title: "Evolution of Digital Organisms at High Mutation Rates Leads to Survival of the Flattest."

This play on Darwin's own "survival of the fittest" incorporates the fact that fitness depends not only on the quantity of offspring an organism can produce in its lifetime, but also how fit those offspring will be.

Lenski and colleagues make the analogy to mountain climbing: the height of the peak you are on is your speed of replication, and the strength of the winds your mutation rate. If there were only a gentle breeze, you would be most fit by climbing to the highest peak you can. But in a more turbulent hurricane, you would want to find someplace where there is not such a long distance to fall - someplace flat.

A fast replicator may be producing many children, but if it's too susceptible to the harmful effects of mutations, it won't contribute to future generations much beyond that. As Lenski put it, "It would have lots of children but not lots of grandchildren."

Specifically, the researchers found that there is tradeoff between producing offspring faster and making them better able to withstand the harmful effects of most mutations. The bottom line: When mutation rates are high, it is better for a species to reproduce more slowly if this allows its offspring to avoid being seriously harmed by mutations.

"Theory predicts that genomes that have evolved at a high mutation rate will have become more robust to the harmful effects of mutations than genomes that have evolved at a low mutation rate," said Lenski, MSU Hannah Professor of Microbial Ecology. "However, theory also predicts that there is a price to be paid for this robustness, which is that more robust genomes will tend to replicate more slowly than genomes that are less robust."

"A species that can reproduce quickly, but loses most of its offspring due to frequent, deleterious mutations may be out-competed by a slower, but more robust species," said Ofria, assistant professor in MSU's Center for Microbial Ecology.

The computer software that creates the digital organisms used to do this work is called "Avida" - A for artificial and vida is Spanish for life. It gives scientists the chance to watch over a period of a few hours a natural evolutionary process that would normally take years.

"Using Avida, the digital organisms can mutate at a rate that we can control in our experiments," Lenski said. "Hence, we let some populations evolve at low and others at high mutation rates and examine the effects on growth and susceptibility to mutation."

The digital organisms are comparable to computer viruses, "except digital organisms are harmless because their programs are meaningless outside the special operating environment in Avida," he said.

The researchers do not put any outside constraints on the computational abilities of these programs.

"Theoretically, any possible algorithm can evolve," said Ofria, the creator of the Avida system. "In fact, in each experiment, the population proceeds along a new evolutionary pathway."

Teaming with Lenski and Ofria on this paper were Christoph Adami of the Jet Propulsion Laboratory, Caltech; and Claus Wilke and Jialan Wang of Caltech's Digital Life Laboratory.

The National Science Foundation funded the work.


Story Source:

The above story is based on materials provided by Michigan State University. Note: Materials may be edited for content and length.


Cite This Page:

Michigan State University. "Digital Organisms Used To Confirm Evolutionary Process." ScienceDaily. ScienceDaily, 19 July 2001. <www.sciencedaily.com/releases/2001/07/010719080551.htm>.
Michigan State University. (2001, July 19). Digital Organisms Used To Confirm Evolutionary Process. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2001/07/010719080551.htm
Michigan State University. "Digital Organisms Used To Confirm Evolutionary Process." ScienceDaily. www.sciencedaily.com/releases/2001/07/010719080551.htm (accessed October 1, 2014).

Share This



More Plants & Animals News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. Video provided by Newsy
Powered by NewsLook.com
California University Designs Sustainable Winery

California University Designs Sustainable Winery

Reuters - US Online Video (Sep. 27, 2014) Amid California's worst drought in decades, scientists at UC Davis design a sustainable winery that includes a water recycling system. Vanessa Johnston reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins