Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




WATER WORLD
New Fish Species Offers Literal Take on 'Hooking Up'
by Staff Writers
Raleigh, NC (SPX) Oct 05, 2012


A magnified view of the four hooked genitalia of the newly identified fish species Gambusia quadruncus.

Fishing hooks aren't the only hooks found in east-central Mexican waters. A new species of freshwater fish described by a North Carolina State University researcher has several interesting - and perhaps cringe-inducing - characteristics, including a series of four hooks on the male genitalia.

Females of the new species - the llanos mosquitofish, or Gambusia quadruncus - also have distinguishing characteristics, including a colorful anal spot.

A paper describing the new species, which lives in a diversity hotspot and seemingly branched off from its closest relative more than one million years ago, appears in the Journal of Fish Biology.

Dr. Brian Langerhans, assistant professor of biology at NC State and the lead author of the paper, says that these interesting characteristics may play important roles in mating control and success.

While more research is needed, Langerhans says that four-hooked genitalia on males can serve a purpose when females attempt to block or restrict mating attempts.

"Typically, reproduction is more costly in females, so females favor ways of reducing mating with 'lower quality' males," Langerhans says, "but reproduction is cheap in males and so selection favors ways of mating with as many females as possible.

"In Gambusia, some females, including G. quadruncus, have evolved modifications that appear to function as a blocking device - essentially a big ball of tissue blocking most of the genital pore - restricting entry of the male's gonopodial tip. Thus, the female would have to behaviorally allow the male to mate or the male would have to evolve a counter response to avoid this problem."

The four-hooked genitalia could be that counter-response, Langerhans says.

"Having four hooks on the gonopodium may provide a means of overcoming female resistance, latching on to the gonopore and transferring sperm in a manner that facilitates effective sperm transfer. Or it may serve to stimulate the female in a manner that causes responses in the female that facilitate effective sperm transfer," Langerhans says.

Somewhat similarly, the colorful anal spot on females appears to serve as a signal that only certain males are desired for mating.

"The differing, species-specific female anal spots appear to influence male mating behavior by signaling the location of the gonopore to the male, sometimes indicating the reproductive status of the female, and distinguishing fish of their own species from fish of other species to reduce costly cross-breeding, which can result in fish with reduced fitness," Langerhans says.

"So it may be that G. quadruncus evolved different anal spots to help reduce interspecies matings and possible formation of hybrids."

Gambusia quadruncus (Cyprinodontiformes: Poeciliidae): A new species of mosquitofish from east-central Mexico; Authors: Brian Langerhans, North Carolina State University; et al Published: September 2012, in Journal of Fish Biology

.


Related Links
North Carolina State University
Water News - Science, Technology and Politics






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





WATER WORLD
The chemical memory of seawater
Bremerhaven, Germany (SPX) Oct 04, 2012
Water does not forget, says Prof. Boris Koch, a chemist at the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association. Irrespective of what happens in the sea: whether the sun shines, algae bloom or a school of dolphins swims through a marine area - everything and everyone leaves biomolecular tracks. With the help of a combination of new techniques, Boris Koch ... read more


WATER WORLD
China has no timetable for manned moon landing

Senior scientist discusses China's lunar orbiter challenges

NASA sees 'gateway' for space missions

Protection for Moon, Mars astronauts eyed

WATER WORLD
NASA rover checks in online from Mars

Russia, U.S. to send crew to ISS for year

From 'Bathurst Inlet' to 'Rocknest'

Gale Crater Set for Summer Heat Wave?

WATER WORLD
Virgin Galactic Acquires Full Ownership of The Spaceship Company

Wind delays Austrian's edge of space jump in US

Brazil's vibrant high-tech industry urged to go global

Uwingu's Crowdfunding Campaign Concludes

WATER WORLD
China Spacesat gets 18-million-USD gov't support

Tiangong Orbit Change Signals Likely Date for Shenzhou 10

China Focus: Timeline for China's space research revealed

China eyes next lunar landing as US scales back

WATER WORLD
Mission accomplished for ATV Edoardo Amaldi

ISS Partners Plan Yearlong Mission to Orbital Station

Space freighter burns up in suicide dive

Space freighter undocking set for Friday

WATER WORLD
SpaceX craft on way to ISS in first supply run

Orbital Begins Antares Rocket Operations at Mid-Atlantic Regional Spaceport

H-IIB Launch Service Privatization

Ariane rocket launches two telecom satellites

WATER WORLD
The Magnetic Wakes of Pulsar Planets

Stagnant Interiors Suppress Chances of Life on Super-Earths

Meteors Might Add Methane to Exoplanet Atmospheres

Two 'hot Jupiters' found in star cluster: NASA

WATER WORLD
Google, publishers end long-running copyright case

Apple even stronger a year after Steve Jobs death

Prehistoric builders reveal trade secrets

Space debris delays Japan's satellite experiment




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement