Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In cordon bleus, song develops independently of sex differences in the brain

04.11.2015

In female songbirds, brain areas responsible for song learning are usually smaller and have fewer neurons compared to males. However, in many species such as the blue-capped cordon bleu, females possess an elaborate song.

Scientists from the Max Planck Institute for Ornithology in Seewiesen now found in this species pronounced sex differences in the brain already in juvenile birds, where females had up to 50% less neurons in the song control areas. However, this had no effect on the song learning process. Only when adult, females had developed a different song with shorter and simpler strophes than males.


Blue-capped cordon-bleus (Uraeginthus cyanocephalus) inspecting a Jackson golden-backed weaver nest (Ploceus jacksoni).

Wolfgang Goymann

In all songbirds investigated to date there are sex differences in those parts of the brain that are responsible for the learning and the production of song. These brain areas are smaller in females and they possess fewer neurons.

This fact is often used as an explanation why females have simpler songs than males or do not sing at all. The neuroanatomical sex differences emerge during development and have a genetic basis or are due to the action of steroid hormones. For example, female song can be induced by the male sex hormone testosterone.

Nevertheless, there are species, in particular in the tropics, where males and females sing nearly similar songs. It is assumed that the song is important for pair bonding and year-round defense of a territory and food resources. Scientists headed by Manfred Gahr from the Max Planck Institute for Ornithology in Seewiesen have for the first time investigated the development of song and the underlying neuroanatomical changes in a species with female song.

Male and female blue-capped cordon bleus that originate from East Africa, start their first vocalizations around the age of 30-40 days. The scientists analyzed different song traits during development in regular intervals and found sex differences only after the birds reached adulthood and were older than 250 days. At that time females suddenly started to sing shorter and simpler songs as their male peers of the same age.

In parallel the scientists investigated the birds’ neuroanatomical properties. Most remarkably, volume and neuron number of the song control regions HVC and RA were smaller in females compared to males from the first point of investigation at day 20 and persisted throughout the entire developmental period.

“These anatomical sex differences are present already in a very early developmental stage and precede the sex differences in song behaviour”, says Manfred Gahr. However, this is not the only amazing result. Despite these different anatomical prerequisites there is a parallel brain development in both sexes. Although the song control centers are up to 55% smaller and have 30-50% fewer neurons, females develop a song comparable to that of males. At least for song learning, these sex differences do not seam to have a functional role.

SSp/HR-MG

Weitere Informationen:

http://www.orn.mpg.de/3639057/news_publication_9725569?c=2732
http://journal.frontiersin.org/article/10.3389/fevo.2015.00117/abstract

Dr. Sabine Spehn | Max-Planck-Institut für Ornithologie

More articles from Life Sciences:

nachricht Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg

nachricht Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Attoseconds break into atomic interior

A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.

In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...

Im Focus: Good vibrations feel the force

A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.

By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Basque researchers turn light upside down

23.02.2018 | Physics and Astronomy

Finnish research group discovers a new immune system regulator

23.02.2018 | Health and Medicine

Attoseconds break into atomic interior

23.02.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>