(Press-News.org) Contact information: Dr. Barbara Caspers
barbara.caspers@uni-bielefeld.de
49-521-106-2825
University of Bielefeld
The more the better!
Study of the University Bielefeld and TU Braunschweig shows the impact of polyandry on reproductive success in fire salamanders
This news release is available in German.
Researchers at Bielefeld University and the Technische Universität Braunschweig are the first to confirm the benefit of multiple paternities for a vertebrate under completely natural conditions. Together with their team, Dr. Barbara Caspers and Dr. Sebastian Steinfartz have shown that female fire salamanders mate with several males under natural conditions
(so-called polyandry). This grants them fitness-relevant benefits by increasing their number of offspring. The results of their study are being published this Friday (29 November) in the Early View version of Molecular Ecology: http://onlinelibrary.wiley.com/doi/10.1111/mec.12577/full. For a long time, it was assumed that females in the animal world are monogamous, that is, they mate with only one male. Males, in contrast, can increase their reproductive success by mating with several females. Nowadays, however, polyandry is assumed to be the rule in the animal world and monogamy to be more of an exception.
Currently, researchers from completely different disciplines are interested in why females mate with several males and what benefits this brings for them or their offspring. There is a particular interest in studies that permit insights and conclusions on these processes under completely natural conditions. As a rule, however, such studies are hard to implement without disturbing the individuals or studying their mating behaviour completely or partially in the laboratory.
Researchers at Bielefeld University's Chair of Animal Behaviour in the group of Dr. Barbara Caspers, Dr. Sebastian Steinfartz, research group leader at the TU Braunschweig, and Professor Michael Kopp from Aix-Marseille University have studied the influence of mating behaviour on the number of offspring in the black and yellow fire salamander (Salamandra salamandra), a widespread European tailed amphibian species. Over the course of the spring season, a female salamander can deposit up to 50 living larvae in small streams and ponds. For their study, the scientists captured female salamanders on their way to deposit their larvae in a forest and took the pregnant females to the laboratory where they deposited their larvae. Every day, the scientists collected the new-born larvae, took a small tissue sample, and returned both mothers and their larvae to the forest. By subjecting these tissue samples to genetic paternity analyses, the researchers could precisely reconstruct how many males each female had mated with and whether or not the sperm of the different males had been mixed – female salamanders can store the sperm of different males for several months in internal receptive organs called spermathecae. The eggs of the female will only be fertilized with the stored sperm, if environmental conditions are optimal and after eggs have developed into full larvae these are deposited in streams and ponds.
It is important to stress that the sperm from the male are deposited on the ground as a sperm packet (called spermatophore) during courtship display, and that the female then actively picks up the spermatophore. Afterwards, the female can decide from which males she will accept sperm or not. Through paternity analyses, the researchers were able to show that some females had mated with as many as four different males. The mixing of the sperm from various males in the spermatheca of the female seems to have quite positive effects, leading to more eggs being fertilized and, as a result, more larvae were finally deposited. Accordingly, polyandry and sperm competition seems to be an important mechanism to increase reproductive success and therefore fitness of a female in this terrestrial vertebrate species.
INFORMATION:
Contact:
Dr. Barbara Caspers, Bielefeld University
Faculty of Biology
Telephone: 0521-106-2825
Email: barbara.caspers@uni-bielefeld.de
Dr. Sebastian Steinfartz, Technische Universität Braunschweig
Zoological Institute
Department of Evolutionary Biology
Telephone: 0531 391 2393
Email: s.steinfartz@tu-bs.de
Further information is available online at:
http://www.uni-bielefeld.de/biologie/vhf/SF/b_caspers.html
The more the better!
Study of the University Bielefeld and TU Braunschweig shows the impact of polyandry on reproductive success in fire salamanders
2013-12-02
ELSE PRESS RELEASES FROM THIS DATE:
Maternal mortality: A reduction in deaths from haemorrhage
2013-12-02
Maternal mortality: A reduction in deaths from haemorrhage
Twenty recommendations have been formulated by the French National Expert Committee on Maternal Mortality with the aim of raising ...
Appearing to be chronically ill may not be a good indication of poor health
2013-12-02
Appearing to be chronically ill may not be a good indication of poor health
From photo, physician accurately identified that a patient was chronically ill in only 45.5 percent of cases
TORONTO, Nov. 27, 2013—Physicians have long been taught that a physical examination ...
Strong dollar means cross-border shopping heavily influenced by exchange rate
2013-12-02
Strong dollar means cross-border shopping heavily influenced by exchange rate
TORONTO, ON - With the holiday shopping season in full swing it appears Canadians now more than ever are keeping a watchful eye on the exchange rate before heading south of the border ...
New family of proteins linked to major role in cancer
2013-12-02
New family of proteins linked to major role in cancer
Scientists have described a new family of proteins that appear to play a key role in cancer and might be targets for future cancer drugs.
A major new study in the journal Nature sets out the structure ...
WSF RIO Declaration goes forward to UN
2013-12-02
WSF RIO Declaration goes forward to UN
Role of science in global sustainability to form basis of post-2015 MDGs
RIO, December 2, 2013: The closing session of the 6th World Science Forum today published its closing declaration with ...
What drives aftershocks?
2013-12-02
What drives aftershocks?
High-resolution GPS signals provide new insights into the mechanisms of stress transfer in subduction zones
On 27 February 2010 an earthquake of magnitude 8.8 struck South-Central Chile near the town of Maule. ...
Marine reserves enhance resilience to climate change
2013-12-02
Marine reserves enhance resilience to climate change
A new study, led by a University of Southampton scientist, highlights the potential for fish communities in marine reserves to resist climate change impacts better than communities on fished coasts.
The ...
Oregon researchers shed new light on solar water-splitting process
2013-12-02
Oregon researchers shed new light on solar water-splitting process
Fundamental discovery could speed development of efficient semiconductor-catalytic junctions
EUGENE, Ore. -- With the help of a new method called "dual-electrode photoelectrochemistry," University of Oregon ...
Koalas' low-pitched voice explained by unique organ
2013-12-02
Koalas' low-pitched voice explained by unique organ
VIDEO:
This video shows the velar fold vibration at 10-45 Hz.
Click here for more information.
...
Microplastics make marine worms sick
2013-12-02
Microplastics make marine worms sick
Tiny bits of plastic trash could spell big trouble for marine life, starting with the worms, say a team of researchers from Plymouth University and the University of Exeter who report their evidence in a pair of studies in the Cell Press ...
LAST 30 PRESS RELEASES:
Decoding plants’ language of light
UNC Greensboro study finds ticks carrying Lyme disease moving into western NC
New implant restores blood pressure balance after spinal cord injury
New York City's medical specialist advantage may be an illusion, new NYU Tandon research shows
Could a local anesthetic that doesn’t impair motor function be within reach?
1 in 8 Italian cetacean strandings show evidence of fishery interactions, with bottlenose and striped dolphins most commonly affected, according to analysis across four decades of data and more than 5
In the wild, chimpanzees likely ingest the equivalent of several alcoholic drinks every day
Warming of 2°C intensifies Arctic carbon sink but weakens Alpine sink, study finds
Bronze and Iron Age cultures in the Middle East were committed to wine production
Indian adolescents are mostly starting their periods at an earlier age than 25 years ago
Temporary medical centers in Gaza known as "Medical Points" (MPs) treat an average of 117 people daily with only about 7 staff per MP
Rates of alcohol-induced deaths among the general population nearly doubled from 1999 to 2024
PLOS One study: In adolescent lab animals exposed to cocaine, High-Intensity Interval Training boosts aversion to the drug
Scientists identify four ways our bodies respond to COVID-19 vaccines
Stronger together: A new fusion protein boosts cancer immunotherapy
Hidden brain waves as triggers for post-seizure wandering
Music training can help the brain focus
Researcher develop the first hydride ion prototype battery
MIT researchers find a more precise way to edit the genome
‘Teen’ pachycephalosaur butts into fossil record
Study finds cocoa extract supplement reduced key marker of inflammation and aging
Obesity treatment with bariatric surgery vs GLP-1 receptor agonists
Nicotinamide for skin cancer chemoprevention
Novel way to ‘rev up’ brown fat burns calories, limits obesity in mice
USC Stem Cell-led team makes major advance toward building a synthetic kidney
Delegation to Artificial Intelligence can increase dishonest behavior
Repeated head impacts cause early neuron loss and inflammation in young athletes
BU study of young athletes finds neurodegeneration might begin before CTEa
Dr. Carl Nathan wins David and Beatrix Hamburg Award
New microscope captures large, high-resolution images of curved samples in single snapshot
[Press-News.org] The more the better!Study of the University Bielefeld and TU Braunschweig shows the impact of polyandry on reproductive success in fire salamanders