Featured Research

from universities, journals, and other organizations

First 'Rule' Of Evolution Suggests That Life Is Destined To Become More Complex

Date:
March 18, 2008
Source:
University of Bath
Summary:
Scientists have revealed what may well be the first pervasive 'rule' of evolution. Researchers have found evidence which suggests that evolution drives animals to become increasingly more complex.

Spiny lobster. In complex crustaceans, such as shrimps and lobsters, almost every segment is different, bearing antennae, jaws, claws, walking legs, paddles and gills.
Credit: iStockphoto/Tammy Peluso

Researchers have found evidence which suggests that evolution drives animals to become increasingly more complex.

Looking back through the last 550 million years of the fossil catalogue to the present day, the team investigated the different evolutionary branches of the crustacean family tree.

They were seeking examples along the tree where animals evolved that were simpler than their ancestors.

Instead they found organisms with increasingly more complex structures and features, suggesting that there is some mechanism driving change in this direction.

“If you start with the simplest possible animal body, then there’s only one direction to evolve in – you have to become more complex,” said Dr Matthew Wills from the Department of Biology & Biochemistry at the University of Bath who worked with colleagues Sarah Adamowicz from from the University of Waterloo (Canada) and Andy Purvis from Imperial College London.

“Sooner or later, however, you reach a level of complexity where it’s possible to go backwards and become simpler again.

“What’s astonishing is that hardly any crustaceans have taken this backwards route. Instead, almost all branches have evolved in the same direction, becoming more complex in parallel.

“This is the nearest thing to a pervasive evolutionary rule that’s been found.

“Of course, there are exceptions within the crustacean family tree, but most of these are parasites, or animals living in remote habitats such as isolated marine caves.

“For those free-living animals in the ‘rat-race’ of evolution, it seems that competition may be the driving force behind the trend.

“What’s new about our results is that they show us how this increase in complexity has occurred. Strikingly, it looks far more like a disciplined march than a milling crowd.”

Dr Adamowicz said: “Previous researchers noticed increasing morphological complexity in the fossil record, but this pattern can occur due to the chance origination of a few new types of animals.

“Our study uses information about the inter-relatedness of different animal groups – the ‘Tree of Life’ – to demonstrate that complexity has evolved numerous times independently.”

Like all arthropods, crustaceans’ bodies are built up of repeating segments. In the simplest crustaceans, the segments are quite similar - one after the other. In the most complex, such as shrimps and lobsters, almost every segment is different, bearing antennae, jaws, claws, walking legs, paddles and gills.

The American biologist Leigh Van Valen coined the phrase ‘Red Queen’ for the evolutionary arms race phenomenon. In Through the Looking-Glass Lewis Carroll’s Red Queen advises Alice that: “It takes all the running you can do, to keep in the same place.”

“Those crustacean groups going extinct tended to be less complex than the others around at the time,” said Dr Wills.

“There’s even a link between average complexity within a group and the number of species alive today.

“All organisms have a common ancestor, so that every living species is part of a giant family tree of life.”

Dr Adamowicz added: “With a few exceptions, once branches of the tree have separated they continue to evolve independently.

“Looking at many independent branches is similar to viewing multiple repeated runs of the tape of evolution.

“Our results apply to a group of animals with bodies made of repeated units. We must not forget that bacteria – very simple organisms – are among the most successful living things. Therefore, the trend towards complexity is compelling but does not describe the history of all life.”

This research was recently published in the Proceedings of the National Academy of Sciences.


Story Source:

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


Cite This Page:

University of Bath. "First 'Rule' Of Evolution Suggests That Life Is Destined To Become More Complex." ScienceDaily. ScienceDaily, 18 March 2008. <www.sciencedaily.com/releases/2008/03/080317171027.htm>.
University of Bath. (2008, March 18). First 'Rule' Of Evolution Suggests That Life Is Destined To Become More Complex. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2008/03/080317171027.htm
University of Bath. "First 'Rule' Of Evolution Suggests That Life Is Destined To Become More Complex." ScienceDaily. www.sciencedaily.com/releases/2008/03/080317171027.htm (accessed July 24, 2014).

Share This




More Plants & Animals News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Boy Attacked by Shark in Florida

Boy Attacked by Shark in Florida

Reuters - US Online Video (July 24, 2014) An 8-year-old boy is bitten in the leg by a shark while vacationing at a Florida beach. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Dogs Appear To Become Jealous Of Owners' Attention

Dogs Appear To Become Jealous Of Owners' Attention

Newsy (July 23, 2014) A U.C. San Diego researcher says jealousy isn't just a human trait, and dogs aren't the best at sharing the attention of humans with other dogs. Video provided by Newsy
Powered by NewsLook.com
Professor Creates Site Revealing Where People's Cats Live

Professor Creates Site Revealing Where People's Cats Live

Newsy (July 23, 2014) ​It's called I Know Where Your Cat Lives, and you can keep hitting the "Random Cat" button to find more real cats all over the world. Video provided by Newsy
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:
from the past week

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