Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

An evolutionary heads-up – The brain size advantage

22.05.2015

Animals with large brains are generally considered to be more intelligent and more successful than those with smaller brains. Researchers from the Vetmeduni Vienna and Stockholm University have now provided the first experimental evidence that large brains provide an evolutionary advantage. In their study, large-brained female fish had a higher survival rate than those with small brains when faced with a predator, although brain size surprisingly did not influence male survival. The results were published in the prestigious journal Ecology Letters.

A larger brain brings better cognitive performance. And so it seems only logical that a larger brain would offer a higher survival potential. In the course of evolution, large brains should therefore win out over smaller ones.


For females, large brains are advantageous.

Photo: Paul Bentzen

Previous tests of this hypothesis had relied on comparison studies looking at the intelligence and survival potential of species with large brains versus species with smaller brains. And species with larger brains do appear to have an advantage. But such studies are unable to show a causal relationship.

Alexander Kotrschal, Sarah Zala, Séverine Büchel and Dustin Penn from the Konrad Lorenz Institute of Ethology at the Vetmeduni Vienna studied fish to answer why investing in a larger brain might provide an evolutionary advantage to compensate for the fact that brain mass is very expensive to develop and maintain.

Research on guppies with large and small brains in semi-natural streams

Guppies are a species of freshwater aquarium fish whose natural range is in the Caribbean region. Kotrschal and his colleagues previously conducted an artificial selection experiment and successfully generated large- and small-brained guppies. In this study, they aimed to test whether brain size influences survival.

Therefore, they released 4,800 guppies from these selection lines into large semi-natural streams, which also contained a natural predator, the pike cichlid. About half a year later, significantly more guppies with large brains had survived. The researchers suggest that large-brained fish have an advantage that allows them to better evade predation. “We have provided the first experimental proof that a large brain offers an evolutionary advantage,” explains first author Kotrschal, who has since moved on to Stockholm University.

Large brains an advantage for females

Large-brained females, whose brains were about 12 percent larger than that of the small-brained females, evaded their predators more often and so had a higher rate of survival. Larger brains did not provide any survival benefit for males. Ethologist Sarah Zala explains: “Male guppies are more colourful and more conspicuous than females and are therefore more easily caught by a predator. A larger brain does not appear to compensate this disadvantage.”

Confirmation of hypothesis on evolution of brain size

“Our findings support the hypothesis that large brains provide a survival benefit under predation pressure,” says co-author Dustin Penn. The first results also suggest that groups of fish with large or small brains behave differently in the presence of the predatory cichlid. This behaviour merits further study. The researchers also want to know whether surviving fish produce more offspring. Genetic analysis should help provide clarity in this regard.

Service:
The article „Brain size affects female but not male survival under predation threat”, by Alexander Kotrschal, Séverine Büchel, Sarah M. Zala, Alberto Corral, Dustin J. Penn and Niclas Kolm was published in Ecology Letters veröffentlicht. doi: 10.1111/ele.12441
http://onlinelibrary.wiley.com/doi/10.1111/ele.12441/abstract

About the University of Veterinary Medicine, Vienna
The University of Veterinary Medicine, Vienna in Austria is one of the leading academic and research institutions in the field of Veterinary Sciences in Europe. About 1,300 employees and 2,300 students work on the campus in the north of Vienna which also houses five university clinics and various research sites. Outside of Vienna the university operates Teaching and Research Farms. http://www.vetmeduni.ac.at

Scientific Contact:
Dr. Alexander Kotrschal
Stockholm University
T +468164046
alexander.kotrschal@zoologi.su.se

Released by:
Susanna Kautschitsch
Science Communication / Public Relations
University of Veterinary Medicine Vienna (Vetmeduni Vienna)
T +43 1 25077-1153
susanna.kautschitsch@vetmeduni.ac.at

Weitere Informationen:

http://www.vetmeduni.ac.at/en/infoservice/presseinformation/press-releases-2015/...

Dr. Susanna Kautschitsch | idw - Informationsdienst Wissenschaft

More articles from Life Sciences:

nachricht Zap! Graphene is bad news for bacteria
23.05.2017 | Rice University

nachricht Discovery of an alga's 'dictionary of genes' could lead to advances in biofuels, medicine
23.05.2017 | University of California - Los Angeles

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: World's thinnest hologram paves path to new 3-D world

Nano-hologram paves way for integration of 3-D holography into everyday electronics

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...

Im Focus: Using graphene to create quantum bits

In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.

In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...

Im Focus: Bacteria harness the lotus effect to protect themselves

Biofilms: Researchers find the causes of water-repelling properties

Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

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

Innovation 4.0: Shaping a humane fourth industrial revolution

17.05.2017 | Event News

 
Latest News

Scientists propose synestia, a new type of planetary object

23.05.2017 | Physics and Astronomy

Zap! Graphene is bad news for bacteria

23.05.2017 | Life Sciences

Medical gamma-ray camera is now palm-sized

23.05.2017 | Medical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>