Navigation Links
Not 1, but 2 kinds of males found in the invasive round goby
Date:6/15/2009

Scientists have found the existence of two types of males of a fiercely invasive fish spreading through the Great Lakes, which may provide answers as to how they rapidly reproduce.

The research, published in the Journal of Great Lakes Research, looks at the aggressive round goby, a bottom-dwelling fish which infested the Great Lakes watersheds around 1990. Presently, they are working their way inland through rivers and canal systems and can lead to the decline of native species through competition and predation.

Researchers at McMaster University discovered evidence that in addition to round goby males which guard the nest from predators and look after their offspring, there exists what scientists call "sneaker" males little males that look like females and sneak into the nests of the larger males.

"The existence of these two kinds of males will help scientists understand how round gobies reproduce, how quickly their populations grow, and track how these populations change over the course of invasion," says Julie Marentette, lead author and a Ph.D. student in the department of Psychology, Neuroscience & Behaviour at McMaster University. "This has the potential to have a significant impact on how researchers tackle what has become a very difficult problem in the Great Lakes."

Because males expend lots of energy or eat less while guarding their nests, and attracting females while providing care can be difficult, males in some species have found a sneakier way to mate, Marentette explains. Instead of courting females and protecting the young, some males will parasitize the courtship and sometimes the parenting duties of conventional males. They do this by sneaking into the nests of big males or pretending to be females.

"Prior to our findings, only one type of male reproductive behaviour would have been incorporated into projections and modeling analyses of the population dynamics of round goby invasive capacities", says Sigal Balshine, associate professor in the department of Psychology, Neuroscience & Behaviour and academic advisor on the study. "Our results will shed light on how populations of this invasive species are likely to grow and spread through time and space."

The McMaster scientists compared the physical, hormonal and sperm traits of hundreds of males, and found that the nest-guarding, parental males were big, black and had wide heads. The small female-like sneaker males were tiny, mottled brown and had narrow heads. Both types of males produced sperm, but sneakers produced more sperm than the parental males, and had bigger testes. By contrast, parental males have bigger glands used to produce pheromones that attract females.


'/>"/>

Contact: Michelle Donovan
donovam@mcmaster.ca
905-525-9140
McMaster University
Source:Eurekalert

Related biology news :

1. Hidden genitalia in female water striders makes males sing
2. Sexual harassment from males prevents female bonding, says study
3. Caffeine appears to be beneficial in males -- but not females -- with Lou Gehrigs disease
4. Caffeine appears to be beneficial in males -- but not females -- with Lou Gehrigs disease
5. Reproductive life of male mice is increased by living with females
6. Study first to pinpoint why analgesic drugs may be less potent in females than in males
7. In spiders, size matters: Small males are more often meals
8. Lightweight and long-legged males go the distance for sex
9. Gene associated with pair-bonding in animals has similar effects in human males
10. Seagulls: Are males the weaker sex?
11. Variety is the spice of life: too many males, too little time...
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/15/2016)... , Jan. 15, 2016 Recent publicized breaches ... to find new ways to ensure data security and ... iOS and Android that ties a ... transforming it into a hardware authorization token. Customer service ... their fingerprint on their KodeKey enabled device to verify ...
(Date:1/13/2016)... 13, 2016 ... of the  "India Biometrics Authentication & ... (2015-2020)"  report to their offering.  ... announced the addition of the  "India ... Estimation & Forecast (2015-2020)"  report ...
(Date:1/11/2016)... , Jan. 11, 2016  higi, the ... nearly 10,000 retail locations, web and mobile, today ... $40 million from existing investors. ... be devoted to further innovate higi,s health platform ... and web portal – including expanding services and ...
Breaking Biology News(10 mins):
(Date:2/3/2016)... ... February 03, 2016 , ... ... series of potential targets (epitopes) specific to misfolded, propagating strains of Amyloid beta ... specific monoclonal antibody therapeutics for Alzheimer’s. , Following on from the first misfolded ...
(Date:2/3/2016)... ... February 03, 2016 , ... Resilinc ... summarizes and analyzes nearly 750 unique supply chain notifications and alerts generated by ... , Supply chain risk management practitioners subscribe to the EventWatch service to receive ...
(Date:2/3/2016)... ALTO, Calif. , Feb. 3, 2016  Today, ... sale of AlphaImpactRx , a leading provider of ... health companies to IMS Health , a global ... AlphaImpactRx,s complementary offerings, capabilities and technologies will be integrated ... company,s growing global primary market research capabilities. ...
(Date:2/3/2016)... ... February 03, 2016 , ... ... two new solutions focused on social housing of small animal models in research ... in data.¹, ² , DSI’s HD-S11 implant has evolved to allow researchers to ...
Breaking Biology Technology: