Navigation Links
First 'rule' of evolution suggests that life is destined to become more complex
Date:3/31/2008

Scientists have revealed what may well be the first pervasive rule of evolution.

In a study published in the Proceedings of the National Academy of Sciences 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 theres 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 its possible to go backwards and become simpler again.

Whats 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 thats 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.

Whats 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 Carrolls 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.

Theres 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.


'/>"/>

Contact: Andrew McLaughlin
a.mclaughlin@bath.ac.uk
44-012-253-86883
University of Bath
Source:Eurekalert

Related biology news :

1. Which came first, the moth or the cactus?
2. First all-African GM crop is resistant to maize streak virus
3. Scientists retrace evolution with first atomic structure of an ancient protein
4. CU-Boulder team discovers first ancient manioc fields in Americas
5. First finding of a metabolite in 1 sex only
6. First orchid fossil puts showy blooms at some 80 million years old
7. First individual genome sequence published
8. U of M begins nations first clinical trial using T-reg cells from cord blood in leukemia treatment
9. UNH becomes first university in nation to use landfill gas as primary energy source
10. Scientists in first global study of poison gas in the atmosphere
11. Weight gain between first and second pregnancies associated with increased odds of male second child
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/11/2017)... 2017 NXT-ID, Inc. (NASDAQ:   NXTD ... the appointment of independent Directors Mr. Robin D. Richards ... of Directors, furthering the company,s corporate governance and expertise. ... Gino Pereira , Chief ... to their guidance and benefiting from their considerable expertise as ...
(Date:4/5/2017)... Today HYPR Corp. , leading innovator ... of the HYPR platform is officially FIDO® Certified ... architecture that empowers biometric authentication across Fortune 500 enterprises ... over 15 million users across the financial services industry, ... product suites and physical access represent a growing portion ...
(Date:4/3/2017)...  Data captured by IsoCode, IsoPlexis Corporation,s ... statistically significant association between the potency of ... objective response of cancer patients post-treatment. The ... cancer patients will respond to CAR-T cell ... to improve both pre-infusion potency testing and cell ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... Proscia ... be hosting a Webinar titled, “Pathology is going digital. Is your lab ready?” ... pathology adoption best practices and how Proscia improves lab economics and realizes an ...
(Date:10/11/2017)... Georgia (PRWEB) , ... October 11, 2017 , ... Disappearing ... taking the lives of over 5.5 million people each year. Especially those living in ... greenovative startup Treepex - based in one of the most pollution-affected countries globally - ...
(Date:10/10/2017)... ... 10, 2017 , ... San Diego-based team building and cooking events company, Lajollacooks4u, ... The bold new look is part of a transformation to increase awareness, appeal ... growth period. , It will also expand its service offering from its signature gourmet ...
(Date:10/10/2017)... ... 2017 , ... Dr. Bob Harman, founder and CEO of VetStem Biopharma, ... The event entitled “Stem Cells and Their Regenerative Powers,” was held on ... DVM, MPVM was joined by two human doctors: Peter B. Hanson, M.D., Chief of ...
Breaking Biology Technology: