Navigation Links
Darkness stifles reproduction of surface-dwelling fish
Date:5/10/2011

There's a reason to be afraid of the dark.

Fish accustomed to living near the light of the water's surface become proverbial "fish out of water" when they move to dark environments like those found in caves, according to a study from North Carolina State University.

In research published this week in Biology Letters, a Royal Society scientific journal, NC State post-doctoral researcher Rdiger Riesch and colleagues found that Atlantic molly females from regular surface streams have a difficult time adjusting to cavelike conditions. Surface female fish had trouble reproducing in the dark conditions, study results show. In addition, many surface-dwelling females introduced to dark conditions surprisingly, according to the researchers suffered from high incidents of stress-induced bacterial columnaris disease, or "fin rot," which causes patchy lesions on the bodies of the fish.

"Permanent darkness severely hampers reproduction in surface-dwelling females," Riesch says. "But this study also shows that the successful colonization of a subterranean habitat must have been a rare event for Atlantic mollies."

The study was designed to provide an answer to why Atlantic mollies their scientific name is Poecilia mexicana living close to each other in and near a cave in southern Mexico can evolve in different ways. These population differences are normally attributed to geographic separation like mountain ridges or some other physical barrier but no physical barrier exists in or around the cave where these Atlantic mollies live.

In the study, the researchers placed some Atlantic mollies in cavelike total darkness while others received a "normal day" of 12 hours of light and 12 hours of darkness.

Most of the cave-dwelling fish of either sex as well as male surface-dwelling fish performed well in both light and darkness. Surface-dwelling females, however, did not breed well or maintain good health in the darkness.

One explanation for the results, Riesch says, has to do with the amount of resources fish have available for reproduction. A fish that has evolved in light has difficulties navigating and finding food in darkness, resulting in reproductive failure.

"Light and dark can completely disrupt life and reproduction for certain fish, and specific key adaptations are necessary to survive in caves," Riesch says. "This study may be one answer to why fish of the same species living side by side can be so different."


'/>"/>

Contact: Rudiger Riesch
rwriesch.evolutionarybiology@gmail.com
919-513-7552
North Carolina State University
Source:Eurekalert  

Related biology news :

1. CU-Boulder study shows 53 million-year-old high Arctic mammals wintered in darkness
2. Beyond sunlight: Explorers census 17,650 ocean species between edge of darkness and black abyss
3. Adapting to darkness: How behavioral and genetic changes helped cavefish survive extreme environment
4. The world is full of darkness, reflected in the physiology of the human retina, Penn researchers say
5. December 2008 highlights from Biology of Reproduction
6. Attitudes towards assisted reproduction and preimplantation genetic diagnosis
7. Low level herbicide use can damage potato reproduction
8. February 2009 highlights from Biology of Reproduction
9. Drugs needed to preserve eggs for reproduction need to be given in stages
10. Yeast missing sex genes undergo unexpected sexual reproduction
11. Study shows value of sexual reproduction versus asexual reproduction
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Darkness stifles reproduction of surface-dwelling fish
(Date:2/13/2017)...  RSA Conference -- RSA, a Dell Technologies business, ... enhance fraud detection and investigation across digital environments ... & Risk Intelligence Suite. The new platform is ... from internal and external sources as well as ... from targeted cybercrime attacks. "Fraudsters are ...
(Date:2/8/2017)... , Feb. 8, 2017 About Voice Recognition ... to match it against a stored voiceprint template. ... pitch, cadence, and tone are compared to distinguish ... hardware installation, as most PCs already have a ... transactions. Voice recognition biometrics are most likely to ...
(Date:2/8/2017)... -- Report Highlights The global biosurgery market ... in 2016 at a compound annual growth rate (CAGR) ... - An overview of the global market for biosurgery. ... 2015 and 2016, and projections of compound annual growth ... on the basis of product type, source, application, and ...
Breaking Biology News(10 mins):
(Date:2/22/2017)... Santa Clara, CA (PRWEB) , ... February 22, 2017 , ... ... is hosting a free AFM Luncheon for all SPIE attendees ... San Jose, CA, just one block from the San Jose Convention Center. The ...
(Date:2/22/2017)... ... February 22, 2017 , ... ... the leading medical education provider of women’s health, primary care, and specialty ... Council for Continuing Medical Education (ACCME). ACCME’s Accreditation with Commendation is a ...
(Date:2/22/2017)... ... February 22, 2017 , ... LabRoots , the ... from around the world, is pleased to announce the launch of a new scholarship ... mathematics (STEM) fields. , This merit-based scholarship is open to all high school seniors, ...
(Date:2/22/2017)... , Feb. 22, 2017 Aethlon Medical, Inc. ... of a study that validated the ability of the ... associated with increased mortality in immune-suppressed sepsis patients and ... The objective of the study was to ... (CMV), Epstein-Barr virus (EBV) and Herpes Simplex virus 1 ...
Breaking Biology Technology: