|
|
 |
|
|
Turtles more closely related to birds than lizards and snakes,genetic evidence shows by ferujkll sdff
|
|
|
Turtles more closely related to birds than lizards and snakes,genetic evidence shows by FERUJKLL SDFF
|
|
| Article Posted: 07/29/2012 |
| Article Views: 112 |
| Articles Written: 2023 - MORE ARTICLES FROM THIS AUTHOR |
| Word Count: 498 |
| Article Votes: 0 |
|
Turtles more closely related to birds than lizards and snakes,genetic evidence shows |
|
|
|
|
|
Business,Business News,Business Opportunities
|
|
Having recently looked at more than a thousand of the least-changedregions in the genomes of turtles and their closest relatives, ateam of Boston University researchers has confirmed that turtlesare most closely related to crocodilians and birds rather than tolizards, snakes, and tuataras. The researchers published their findings in the Royal Societyjournal Biology Letters . By showing that turtles are closer relatives to crocodiles andbirds (archosaurs) than lizards, snakes and tuatara (lepidosaurs),the study challenges previous anatomical and paleontologicalassessments. Nick Crawford, a post-graduate researcher in biologyin BU's Graduate School of Arts & Sciences and lead author ofthe study, achieved these findings by using computational analysisto examine regions of the different animals' genomes. "Turtles have been an enigmatic vertebrate group for a longtime and morphological studies placed them as either most closelyrelated to the ancestral reptiles, that diverged early in thereptile evolutionary tree, or as closer to lizards, snakes, andtuataras," says Crawford.
The study is the first genomic-scale analysis addressing thephylogenetic position of turtles, using over 1000 loci fromrepresentatives of all major reptile lineages including tuatara(lizard-like reptiles found only in New Zealand). Earlier studiesof morphological traits positioned turtles at the base of thereptile tree with lizards, snakes and tuatara (lepidosaurs),whereas molecular analyses typically allied turtles with crocodilesand birds (archosaurs). The BU researchers challenged a recent analysis of shared microRNAfamilies that suggested turtles are more closely related tolepidosaurs. They did this with data from many single-copy nuclearloci dispersed throughout the genome, using sequence capture,high-throughput sequencing and published genomes to obtainsequences from 1145 ultraconserved elements (UCEs) and theirvariable flanking DNA.
The resulting phylogeny providesoverwhelming support for the hypothesis that turtles evolved from acommon ancestor of birds and crocodilians, rejecting thehypothesized relationship between turtles and lepidosaurs. The researchers used UCEs because they are easily aligned portionsof extremely divergent genomes, allowing many loci to beinterrogated across evolutionary timescales, and because sequencevariability within UCEs increases with distance from the core ofthe targeted UCE, suggesting that phylogenetically informativecontent in flanking regions can inform hypotheses spanningdifferent evolutionary timescales. The combination of taxonomicsampling, the genome-wide scale of the sampling and the robustresults obtained, regardless of analytical method, indicates thatthe turtle-archosaur relationship is unlikely to be caused bylong-branch attraction or other analytical artefacts. The BU study is the first to produce a well-resolved reptile treethat includes the tuatara and multiple loci, and also is the firstto investigate the placement of turtles within reptiles using agenomic-scale analysis of single-copy DNA sequences and a completesampling of the major relevant evolutionary lineages.
Because UCEsare conserved across most vertebrate groups and found in groupsincluding yeast and insects, this framework is generalizable beyondthis study and relevant to resolving ancient phylogenetic enigmasthroughout the tree of life. This approach to high throughputphylogenomics -- based on thousands of loci -- is likely tofundamentally change the way that systematists gather and analysedata. I am Computer Hardware & Software writer, reports some information about planon docupen scanner , ratchet load binders.
Related Articles -
planon docupen scanner, ratchet load binders,
|
Rate This Article  |
|
|
|
|
|
Do you Agree or Disagree? Have a Comment? POST IT!
| Reader Opinions |
|
|
|
|
|
|
|
|
|
| Author Login |
|
|
 |
Advertiser Login
ADVERTISE HERE NOW!
Limited Time $60 Offer!
90 Days-1.5 Million Views
|
|
TIM FAY
After 60-plus years of living, I am just trying to pass down some of the information that I have lea...more
|
|
|
|
|
ALEX BELSEY
I am the editor of QUAY Magazine, a B2B publication based in the South West of the UK. I am also the...more
|
|
|
|
|
ABDUL HAYE AMIN
Background Information
Abdul Haye Amin is the author of new book of poetry in language English ...more
|
|
|
|
|
LAURA JEEVES
At LeadGenerators, we specialise in content-led Online Marketing Strategies for our clients in the t...more
|
|
|
|
|
STEPHEN BYE
Stephen Bye is a fiction writer. His most recent novels are a 5-book “The Developer” series which be...more
|
|
|
|
|
PAUL PHILIPS
For more articles, blog messages & videos and a free e-book download go to www.NewParadigm.ws your p...more
|
|
|
|
|
LEVAL AINAH
I am an internet marketer and also an educator. My goal is to help others who are looking to improve...more
|
|
|
|
|
GENE MYERS
Author of four books and two screenplays; frequent magazine contributor. I have four other books "in...more
|
|
|
|
|
ADRIAN JOELE
I have been involved in nutrition and weight management for over 12 years and I like to share my kn...more
|
|
|
|
