Navigation Links
Research team finds first evolutionary branching for bilateral animals
Date:9/23/2009

PROVIDENCE, R.I. [Brown University] When it comes to understanding a critical junction in animal evolution, some short, simple flatworms have been a real thorn in scientists' sides. Specialists have jousted over the proper taxonomic placement of a group of worms called Acoelomorpha. This collection of worms, which comprises roughly 350 species, is part of a much larger group called bilateral animals, organisms that have symmetrical body forms, including humans, insects and worms. The question about acoelomorpha, was: Where do they fit in?

To scientists, acoelomorpha, has been enigmatic, a "rogue animal," said Casey Dunn, an evolutionary biologist at Brown University. "It has been wandering throughout the animal tree of life."

The worm wanders no more. Through a laborious genetic sequencing analysis, Dunn and an international team of scientists have settled the long-standing debate and determined that acoelomorpha belongs as a sister clade to other bilateral animals. The finding is significant, Dunn said, because it shows the worm is a product of the deepest split within the bilateral animals, the first evolutionary divergence within the group. Because of that, scientists have gained a key insight into the most recent common ancestor to bilaterians, a species that remains unknown.

The worm is "as distant as an animal can be in bilateria and still be a bilaterian," said Dunn, assistant professor of biology. "So, now we have two perspectives to (find out about) this common ancestor, the acoelomorphs and all the other bilateral animals."

The results appear online this week in the Proceedings of the Royal Society B.

The team, composed of 17 scientists from the United States, France Germany, Sweden, Spain and the United Kingdom, had two more interesting findings:

  • The debate appears to be over for Xenoturbella, a type of marine worm whose ancestral affiliation had been tossed between worms and mollusks. The researchers reported their genetic analysis shows diminishing evidence for placing xenoturbella within Deuterostomia, one of the major groups within the animal kingdom. Coincidentally, it also shows that xenoturbella may be a close relative to acoelomorpha.
  • Cycliophora, a single species discovered in 1994 that lives on the bristles surrounding the mouth of the Norway lobster Nephrops norvegicus, has found a home with Entoprocta and Ectoprocta. The researchers base their findings on an analysis that reached further into the genetic makeup of cycliophora than previous studies had done.

The team used a genetic sequencing technique called expressed sequence tags to carry out the phylogenetic studies. The aim of this approach, discusssed in a study led by Dunn that appeared in Nature last year, is to analyze a large number of genes from a large number of animals. For this paper, the researchers looked at 1,487 genes, a 10-fold increase in the number of genes analyzed in previous studies. In all, the researchers logged 2.25 million processor hours on a supercomputer in California to obtain the results. Dunn called the effort the most computationally intensive phylogenetic analysis to date.


'/>"/>

Contact: Richard Lewis
Richard_Lewis@Brown.edu
401-863-3766
Brown University
Source:Eurekalert  

Related biology news :

1. 57 college presidents declare support for public access to publicly funded research in the US
2. Georgia State researcher to use $1 million grant to improve computer models for fighting wildfires
3. LSUHSC researchers working to prevent diabetic neuropathy
4. UAB research finds childbearing increases chance of developing the metabolic syndrome
5. Researcher awarded $1.2 million grant to study centrosomes and cilia
6. UAB research team saves turtle species on the brink
7. Nanoresearchers challenge dogma in protein transportation in cells
8. Ben-Gurion University Alzheimers researcher demonstrates specific immune response to vaccine
9. 1 million euro EU grant for MDC diabetes researcher Dr. Francesca M. Spagnoli
10. MDC researchers discover molecule responsible for axonal branching
11. Cybernetwork to help K-State researchers study tallgrass prairie, respond to global warming
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Research team finds first evolutionary branching for bilateral animals
(Date:6/22/2016)... , June 22, 2016 On Monday, ... call to industry to share solutions for the Biometric ... U.S. Customs and Border Protection (CBP), explains that CBP ... are departing the United States , ... and to defeat imposters. Logo - ...
(Date:6/20/2016)... , June 20, 2016 Securus ... justice technology solutions for public safety, investigation, corrections ... the prisons involved, it has secured the final ... (DOC) facilities for Managed Access Systems (MAS) installed. ... additional facilities to be installed by October, 2016. ...
(Date:6/15/2016)... June 15, 2016 Transparency ... titled "Gesture Recognition Market by Application Market - Global Industry Analysis ... 2024". According to the report, the  global gesture recognition ... 2015 and is estimated to grow at a ... by 2024.  Increasing application of gesture ...
Breaking Biology News(10 mins):
(Date:6/24/2016)... , June 24, 2016 Epic Sciences ... detects cancers susceptible to PARP inhibitors by targeting ... cells (CTCs). The new test has already been ... in multiple cancer types. Over 230 ... damage response pathways, including PARP, ATM, ATR, DNA-PK ...
(Date:6/24/2016)... ... , ... Researchers at the Universita Politecnica delle Marche in Ancona combed medical ... mesothelioma. Their findings are the subject of a new article on the Surviving Mesothelioma ... in the blood, lung fluid or tissue of mesothelioma patients that can help point ...
(Date:6/23/2016)... ... 23, 2016 , ... UAS LifeSciences, one of the leading ... UP4™ Probiotics, into Target stores nationwide. The company, which has been manufacturing high ... its list of well-respected retailers. This list includes such fine stores as Whole ...
(Date:6/23/2016)... 2016 /PRNewswire/ - FACIT has announced the creation ... biotechnology company, Propellon Therapeutics Inc. ("Propellon" or "the ... a portfolio of first-in-class WDR5 inhibitors for the ... WDR5 represent an exciting class of therapies, possessing ... for cancer patients. Substantial advances have been achieved ...
Breaking Biology Technology: