Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

For a male sand goby, playing ’Mr. Mom’ is key to female’s heart

05.05.2004


What’s a little male fish’s secret weapon for attracting the lady fish? Something some guys but few other males in the animal kingdom have thought of: It acts like a good dad.



Sand gobies, small fish native to the European coast, are among about 20 percent of fish families worldwide that display some form of care for eggs or hatchlings. But in experiments reported in the current issue of the journal Behavioral Ecology, a team that includes a University of Florida scientist reports that male sand gobies work harder at building nests and taking care of eggs when females are present – the first time such "courtship parental care" has been documented in any species.

Some males’ behavior was even more dastardly. While the experiments showed all male gobies nibbled on the eggs in their charge, unaccompanied males not only shirked their parental duties – they also were more likely to gobble down entire clutches of eggs.


"We were interested in whether males would change their behavior in response to the perception that their future mating opportunities were different," said Colette St. Mary, an associate professor of zoology at UF and one of three authors of the paper. "We found this was the case."

Sigal Balshine, an assistant professor of psychology and specialist in animal behavior at McMaster University in Ontario, called the results "very neat and very novel."

Asked about analogies to human behavior, she said, "Being a good father is very sexy. This is almost a cliché, as it has become a standard joke that the best way to get women to be interested in you as a single guy is to borrow a baby or a puppy. Women obviously find ’caring guys’ very sexy."

As part of a research effort aimed at investigating the role of sexual selection in how parental care has evolved in male fish, St. Mary, Kai Lindström and Christophe Pampoulie, both of the University of Helsinki in Finland, decided to use sand gobies to test a theory that males would provide more care for their young if females were present.

Both humans and animals often engage in two-faced behavior. But the general rule in biology is that parenting duties conflict with reproductive activity, because males would devote their energy to taking care of offspring instead of courting and mating.

"Traditionally evolutionary biologists have thought that parental care is something that is costly to other components of fitness, such as survival, growth or looking for other opportunities to reproduce," Balshine said.

Sand gobies nest under mussel and other shells, and the males not only find and defend these shells, they also hollow out a space under them and pile sand on top to disguise them from predators, St. Mary said. The fish also use their pectoral fins to fan water over the eggs, creating a current of fresh, oxygenated water needed for them to mature.

In the experiment, the researchers allowed male and female gobies to mate, then exposed half the males to additional females, which were placed in a small compartment that allowed the males to see the females and "be in chemical contact with them" but prevented physical contact, the authors write. Some males were in small nests while others were in larger ones, a variable used to determine whether nest size also played a role in the males’ courting behavior. The researchers then compared the parenting efforts by the accompanied and unaccompanied males.

The researchers used a total of 48 male gobies and at least 72 females to test different combinations of nest size, female presence and absence. They filmed the males for 30-minute intervals on the second day after spawning. The results were unambiguous.

"We found that males fanned (the eggs) longer and more frequently, and did more nest construction in the presence of females and in big nests," the authors write.

Also, unaccompanied males in small nests were most likely to eat all of their eggs, the authors noted. Bigger nests provide space for additional mating, encouraging the males to improve their parenting appearances, she said.

St. Mary added that although the parental courtship behavior is the first-ever documented experimentally, a few other species have been observed doing something similar in the wild. For example, three-spined stickleback male fish fan their nests before receiving eggs, a behavior termed "courtship fanning." Also, some species of male birds and insects feed their female counterparts prior to mating, which could be interpreted as combining the twin goals of attracting mates and parenting, she said.

Although the experiments show that males improve their parental duties in response to the presence of females, the studies don’t indicate whether it actually pays off in terms of wooing females to mate. St. Mary and her colleagues plan to take up that issue in experiments this summer.



###
Writer: Aaron Hoover, 352-392-0186, ahoover@ufl.edu
Source: Colette M. St. Mary, (011) 358-0-9-191-57800 (2-4 p.m. EST), stmary@zoo.ufl.edu

Aaron Hoover | EurekAlert!

More articles from Life Sciences:

nachricht New photocatalyst speeds up the conversion of carbon dioxide into chemical resources
29.05.2017 | DGIST (Daegu Gyeongbuk Institute of Science and Technology)

nachricht Copper hydroxide nanoparticles provide protection against toxic oxygen radicals in cigarette smoke
29.05.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Strathclyde-led research develops world's highest gain high-power laser amplifier

The world's highest gain high power laser amplifier - by many orders of magnitude - has been developed in research led at the University of Strathclyde.

The researchers demonstrated the feasibility of using plasma to amplify short laser pulses of picojoule-level energy up to 100 millijoules, which is a 'gain'...

Im Focus: Can the immune system be boosted against Staphylococcus aureus by delivery of messenger RNA?

Staphylococcus aureus is a feared pathogen (MRSA, multi-resistant S. aureus) due to frequent resistances against many antibiotics, especially in hospital infections. Researchers at the Paul-Ehrlich-Institut have identified immunological processes that prevent a successful immune response directed against the pathogenic agent. The delivery of bacterial proteins with RNA adjuvant or messenger RNA (mRNA) into immune cells allows the re-direction of the immune response towards an active defense against S. aureus. This could be of significant importance for the development of an effective vaccine. PLOS Pathogens has published these research results online on 25 May 2017.

Staphylococcus aureus (S. aureus) is a bacterium that colonizes by far more than half of the skin and the mucosa of adults, usually without causing infections....

Im Focus: A quantum walk of photons

Physicists from the University of Würzburg are capable of generating identical looking single light particles at the push of a button. Two new studies now demonstrate the potential this method holds.

The quantum computer has fuelled the imagination of scientists for decades: It is based on fundamentally different phenomena than a conventional computer....

Im Focus: Turmoil in sluggish electrons’ existence

An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.

We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...

Im Focus: Wafer-thin Magnetic Materials Developed for Future Quantum Technologies

Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.

Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Marine Conservation: IASS Contributes to UN Ocean Conference in New York on 5-9 June

24.05.2017 | Event News

AWK Aachen Machine Tool Colloquium 2017: Internet of Production for Agile Enterprises

23.05.2017 | Event News

Dortmund MST Conference presents Individualized Healthcare Solutions with micro and nanotechnology

22.05.2017 | Event News

 
Latest News

New insights into the ancestors of all complex life

29.05.2017 | Earth Sciences

New photocatalyst speeds up the conversion of carbon dioxide into chemical resources

29.05.2017 | Life Sciences

NASA's SDO sees partial eclipse in space

29.05.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>