(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:
Smarter tools for policymakers: Notre Dame researchers target urban carbon emissions, building by building
Here’s how we help an iconic California fish survive the gauntlet of today’s highly modified waterways
New technique can dramatically improve laser linewidth
Forest trees and microbes choreograph their hunt for a ‘balanced diet’ under elevated CO2
Beyond health: The political effects of infectious disease outbreaks
For tastier and hardier citrus, researchers built a tool for probing plant metabolism
Stay hydrated: New sensor knows when you need a drink
Quantum internet meets space-time in this new ingenious idea
Soil erosion in mountain environments accelerated by agro-pastoral activities for 3,800 years
Optogenetic platform illuminates new antiviral strategies
A new theory explaining oscillations in tunnel magnetoresistance (TMR)
Early antibiotics alter immune function in infants
With the second grant to therapy
Research center developing digital twins for manufacturing
Colombia’s biofortified rice has untapped potential to improve nutrition. And consumers want it
Study shows pregnancy can significantly worsen risk of serious brain injury in women with arteriovenous malformations
Mapping important infrastructure could aid emergency response after hurricanes
Nighttime pistachio snacking may reshape gut microbiome in prediabetic adults
Friendship promotes neural and behavioral similarity
Neural pathway for nicotine withdrawal symptoms
How your DNA reveals your true age with astonishing accuracy
First electronic–photonic quantum chip created in commercial foundry
High-performance scientific computing can compute molecule ground-state energy
Cryo-electron microscopy – Reaction cycle of an enzyme for CO2 fixation decoded
Feeling more extroverted? Study finds you may have learned how to handle daily stress better
Kindness counts—even to a five-day-old baby
Endocrine Society guideline calls for increased screening for common cause of high blood pressure
Macromolecular gene delivery systems: advancing non-viral therapeutics with synthetic and natural polymers
Study finds political instability, environmental conditions, and social inequality accelerate aging
New insights into malaria: Proteins in the blood can reveal the severity of the disease
[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