Navigation Links
New fins evolve repeatedly in teleost fishes
Date:3/5/2014

Though present in more than 6,000 living species of fish, the adipose fin, a small appendage that lies between the dorsal fin and tail, has no clear function and is thought to be vestigial. However, a new study analyzing their origins finds that these fins arose repeatedly and independently in multiple species. In addition, adipose fins appear to have repeatedly and independently evolved a skeleton, offering a glimpse into how new tissue types and structural complexity evolve in vertebrate appendages.

Adipose fins therefore represent a unique example of convergent evolution and new model for exploring the evolution of vertebrate limbs and appendages, report scientists from the University of Chicago in the Proceedings of the Royal Society B on March 5.

"Vertebrates in general have conserved body plans, and new appendages, whether fins or limbs, evolve rarely," said senior author Michael Coates, PhD, chair of the Committee on Evolutionary Biology at the University of Chicago. "Here, we have a natural experiment re-run repeatedly, providing a superb new system in which to explore novelty and change."

Usually small and structurally simple, adipose fins tend to get attention only when they are clipped from farm-raised trout and salmon as a tag. Despite their presence in thousands of fish species, they have been dismissed as a remnant of a once-functional fin. This assumption puzzled Coates and co-authors, as they saw no evidence of deterioration in adipose fin structure or function in the fossil record.

To study the evolutionary origins of this fin, Coates and lead author Thomas Stewart, graduate student in organismal biology and anatomy at the University of Chicago, turned to a technique known as ancestral-state reconstruction. With co-author W. Leo Smith, PhD, from the Biodiversity Institute at the University of Kansas, they created an evolutionary tree describing the relationships between fish with and without adipose fins, using genetic information from more than 200 ray-finned fish and fossil data from known time points. They then used statistical models to predict when and in what species the adipose fin might have first evolved.

They found that adipose fins originated multiple times, independently, in catfish and other groups of ray-finned fishesa striking example of convergent evolution over a vast range of species.

"It's pretty incredible that a structure which is incredibly common could be so misunderstood," Stewart said. "Our finding, that adipose fins have evolved repeatedly, shows that this structure, long assumed to be more-or-less useless, might be very important to some fishes. It's exciting because it opens up new questions."

More than 600 species of fish were studied in the course of this research, including many from the collections of the Field Museum in Chicago. This analysis revealed that a number of complex skeletal structures, including spines, plates, fin rays and cartilage discs, evolved independently in the adipose fins of different species. And while studies of the fossil record have suggested that new fins originate in a predictable and repeated manner, adipose fins demonstrate multiple routes to building new appendages.

"These results challenge what was generally thought for how new fins and limbs evolve, and shed new light on ways to explore the full range of vertebrate limb and fin diversity," Stewart notes.


'/>"/>
Contact: Kevin Jiang
kevin.jiang@uchospitals.edu
773-795-5227
University of Chicago Medical Center
Source:Eurekalert  

Related biology news :

1. Social or stinky? New study reveals how animal defenses evolve
2. From one cell to many: How did multicellularity evolve?
3. Study offers clues to how plants evolved to cope with cold
4. How does inbreeding avoidance evolve in plants?
5. 3D simulation shows how form of complex organs evolves by natural selection
6. Virtual, squishy creatures evolve to run using evolutionary algorithms
7. How human language could have evolved from birdsong
8. Birds evolved ultraviolet vision several times
9. Tumors evolve rapidly in a childhood cancer, leaving fewer obvious tumor targets
10. Why some grasses evolved a more efficient photosynthesis and others didnt
11. New study sheds light on how and when vision evolved
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
New fins evolve repeatedly in teleost fishes
(Date:6/22/2016)... , June 22, 2016   Acuant ... and verification solutions, has partnered with RightCrowd ... solutions for Visitor Management, Self-Service Kiosks and ... products that add functional enhancements to existing ... corporations and venues with an automated ID ...
(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 ...
(Date:6/2/2016)... , June 2, 2016 The ... has awarded the 44 million US Dollar project, for ... Embossed Vehicle Plates including Personalization, Enrolment, and IT Infrastructure ... leader in the production and implementation of Identity Management Solutions. ... January, however Decatur was selected for ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... ... 2016 , ... Parallel 6 , the leading software as a service ... Virtual Patient Encounter CONSULT module which enables both audio and video telemedicine communication ... , Using the CONSULT module, patients and physicians can schedule a face to face ...
(Date:6/27/2016)... , ... June 27, 2016 , ... ... for Amgen, will join the faculty of the University of North Carolina ... professor of strategy and entrepreneurship at UNC Kenan-Flagler, with a focus on the ...
(Date:6/27/2016)... June 27, 2016   Ginkgo Bioworks , a ... engineering, was today awarded as one of the ... the world,s most innovative companies. Ginkgo Bioworks is ... the real world in the nutrition, health and ... directly with customers including Fortune 500 companies to ...
(Date:6/24/2016)... SAN DIEGO , June 24, 2016 /PRNewswire/ ... that more sensitively detects cancers susceptible to PARP ... individual circulating tumor cells (CTCs). The new test ... of HRD-targeted therapeutics in multiple cancer types. ... therapies targeting DNA damage response pathways, including PARP, ...
Breaking Biology Technology: