Dawn song of the male great tit attracts other males rather than females

JUNE 23, 2020

by Wageningen University

Female great tits (Parus major) stay clear of territories with better singing males while competing males are attracted to the territories with better singers. This unexpected conclusion was reached by researchers of Wageningen University & Research in collaboration with the Netherlands Instituut for Ecology (NIOO-KNAW). This conclusion is diametrically opposed to the current assumption that male birds use their song to impress females and repel males to stay away from their territory.

Previous research showed that songbirds often cheat on their partners. One would thus expect male birds to use their song to lure any close-by females. But nature tells a different story, the research team discovered.

"Our knowledge to date on the daily behavior between males and females is largely based on knowledge under lab condition because it is so difficult to follow a songbird for a long time," professor Marc Naguib explains. "We know what colors are prefered by the females, and what songs they prefer if they exhibit an immediate reaction. But how they show territorial behavior and respond to males in the open field was hitherto almost unknown."

Dawn song attracts male competition

Ph.D. researcher Nina Bircher and her co-authors expected that the most enthusiastic singers would attract the most female interest. This appeared completely false. The male great tits with the most extensive repertoire that started singing the earliest and showed the most persistence attracted fewer females. Male great tits, however, entered their singing competitor's territory, captivated by the performance, the researchers write in the scientific journal Behavioral Ecology.

The reason for this behavior remains a mystery. Naguib: "Males may enter the competitor's territory to check out why the competitor is better than they are, or why he may be more suited to produce offspring." Whatever the reasons, the discovery sheds new light on the complexity of songbirds social and communication network.

The prevailing assumption that the female great tit would more frequently enter a different territory when she is fertile is thus not supported. The premise is she would visit other territories specifically for extra-pair mating. In reality, however, this research shows that she enters territories other than her own once she has laid eggs in an effort to find food for her young.

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CENSUS: GREAT TIT MOST COMMON BIRD IN CZECH REPUBLIC

 Ian Willoughby

 07-01-2019

Over 10,000 people took part in the first ever bird census in the Czech Republic at the weekend. The participants sent information about the birds they had observed in their gardens and elsewhere to the website of the Czech Ornithological Society. Volunteers registered almost a quarter of a million birds of dozens of species. 

According to preliminary results, the most reported bird was the great tit, which finished far ahead of the tree sparrow and house sparrow.

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Urban bird species risk dying prematurely due to stress

LUND UNIVERSITY

Birds of the species Parus Major (great tit) living in an urban environment are at greater risk of dying young than great tits living outside cities. Research results from Lund University in Sweden show that urban great tits have shorter telomeres than others of their own species living in rural areas. According to the researchers, the induced stress that the urban great tits are experiencing is what results in shorter telomeres and thereby increases their risk of dying young.

Telomeres are located at the end of each DNA strand in the body's chromosomes, in both great tits and humans. The length of the telomeres can be described as a kind of age biomarker - short telomeres mean short life expectancy. According to the researchers, their study shows that the environment in which great tits grow up determines the length of their telomeres more than their genetics.

"Although there are advantages to living in cities, such as the access to food, they seem to be outweighed by the disadvantages, such as stress - at least in terms of how quickly the cells of the great tits age", says biologist Pablo Salmón who conducts research in the field of evolutionary ecology at the Faculty of Science, Lund University.

The researchers obtained the results by studying great tit groups of siblings. Half of the siblings grew up in the countryside, half in Malmö. After 13 days, blood was taken to measure the length of their red cell telomeres. Pablo Salmón and his colleagues had partly anticipated the outcome, but were still surprised when they saw how big the difference in the length of the telomeres was after only 13 days.

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Songbird's reference genome illuminate key role of epigenetics in evolution of memory and learning

Smart songbird's reference genome is milestone for ecological research

Date:January 25, 2016

Source:Netherlands Institute of Ecology (NIOO-KNAW)

A well-known songbird, the great tit, has revealed its genetic code, offering researchers new insight into how species adapt to a changing planet. Their initial findings suggest that epigenetics -- what's on rather than what's in the gene -- may play a key role in the evolution of memory and learning. And that's not just true for birds. An international research team led by the Netherlands Institute of Ecology (NIOO-KNAW) and Wageningen University will publish these findings in Nature Communications on Monday.

"People in our field have been waiting for this for decades," explain researchers Kees van Oers and Veronika Laine from the Netherlands Institute of Ecology. The reference genome of their favourite model species, the great tit, is "a powerful toolbox that all ecologists and evolutionary biologists should know about."

Coming from a single Dutch bird, the genetic code of the assembled reference genome will help to reveal the genetic basis of phenotypic evolution. This is essential for understanding how wild species adapt to our changing planet.

In addition to looking at the genome, the research team have also determined the so-called transcriptome and methylome. The latter belongs to the field of epigenetics: the study of what you can inherit not in but 'on' your genes. Specific DNA sequences in the genome can be 'methylated': methyl groups are added to them, modifying how the genes function.

The research team sequenced the complete genomes of a further 29 great tit individuals from different parts of Europe. This enabled them to identify regions in the great tit's genome that have been under selection during recent evolution of the bird. These regions appeared to be overrepresented for genes related to learning and cognition.

"The great tit has evolved to be smart," says Van Oers. "Very smart." It's not your average bird, as it belongs to the top 3% smartest birds when it comes to learning new behaviour. That makes it a perfect candidate for research into the evolution of learning, memory and cognitive processes.

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Nature Versus Nurture: Better Looking Birds Have Healthier Babies, Finds Study of Great Tits

Mar. 25, 2013 — A female great tits' (Parus major) appearance is shown to signal healthy attributes in offspring in a paper in BioMed Central's open access journal Frontiers in Zoology. The black stripe across her breast and white patches on her cheeks correlate to a chick's weight at two weeks and immune strength respectively -- though the former seems to signal a genetic benefit and the latter can affect an 'adopted' chick's health, suggesting nurture is involved.

Taking two mothers with different patterning, and swapping their chicks, researchers from Palacky University in the Czech Republic were able to investigate the growth and health of the infants and the 'ornamentation' of their mothers. They compared the offspring's weight, size and immune strength and found a correlation between the chick's weight at two weeks and the size of black breast stripe on the genetic mother.

The immaculateness of both genetic and foster mother's white cheek patch was related to the strength of chick's immune response suggesting that this was due to both nurture and genetics. In contrast the body size of a chick was related only to the body size of its genetic mother and not to ornamentation at all.

In these socially monogamous birds both the males and females are brightly coloured, however neither the cheek patch nor the stripe in males affected the health of the babies.

Talking about how the ornaments can have evolved to signal reproductive fitness, Vladimír Remeš and Beata Matysioková who performed this study explained, "Bigger healthier babies are important to the reproductive success of individuals, because they are more likely to survive to adulthood -- so it is useful for birds to be able to work out which potential mates will produce the best babies. Maintaining bright colouration uses up resources which could otherwise be invested in reproduction or self-maintenance -- consequently the evolution and maintenance of ornamentation in female great tits is probably due to direct selection by males."

http://www.sciencedaily.com/releases/2013/03/130324201814.htm

Clever birds don't have it all

Studies show some great tits are remarkably clever when it comes to solving problems to get at food. But does this help them in the wild?

BE CAREFUL who you call a bird brain, you may be paying them a compliment. Some bird species exhibit remarkable intelligence, among them the great tit, which is a common garden bird.

The New Caledonian crow is top of the leader board with its capacity to fashion tools to retrieve food, but the local great tit doesn’t do too badly when it comes to solving problems. Dr John Quinn, a specialist in animal personality and cognition, began to study the bird four years ago while at Oxford University. He and his team caught wild great tits in a nearby wood and set the birds a simple problem. If they solved it, they would get at some food.

Now a lecturer in ecology at University College Cork, Quinn had a particular purpose in mind when conducting the experiments. “We are trying to understand why we get individual variations in the birds’ cognitive ability,” he says.

They were also trying to discover whether it is “better to be brighter” – whether the birds that were able to solve the puzzle also did better generally, either reproductively or in terms of survival. “The purpose of our study was simple: to test if it was better being a problem-solver. That hadn’t been tested in the past. Do they do better or do all individuals do equally well in the end?

Continued:  http://www.irishtimes.com/newspaper/sciencetoday/2012/1018/1224325405737.html