Dominance & weight

My father used to remind me: "Be very careful with other people's money, little man".

The banks are us, "the people", especially with their most sensitive side, their pennies. Money is a source of existential security: the future, independence, freedom, satisfaction, power, access to property, etc.

The bankers are the high priests of the money world.Today, more than ever, they are under pressure from public opinion because of their shameless greed and lack of scruples. But the banks, that's us, are in charge of people's money for a fee, mainly for the satisfaction of primitive instincts, primitive greed...

Their products and the game's rules are purely technical, focusing solely on returns and risk management (loss, fraud). No matter how friendly and trustworthy they are, banks always have their fundamental image problem: they are socially worthless and drain society.

But the banks ... that means we …

Meanwhile, weather stations worldwide have recorded the warmest summer on record. It will also be the coolest of all the years to come...

This is also caused by ... ourselves ... so to speak.

Testosterone, a predominantly male hormone, drives many beneficial processes and the antisocial behaviour that underlies these harmful excesses.

Women have significantly less testosterone, making them better suited to the current world order in many ways than men. They are in charge of the long-term rescue of our planet's ecosystem, which is in great distress and vital to all biological life.

Humanity increasingly recognises the urgency but must first pass the buck regarding who will foot the bill for averting catastrophe. Moreover, "truth as a cardinal point" in Western democracies will likely be lost globally. Major autocratic powers have not experienced these hard-won "enlightenment values". Visiting the Pantheon in Paris is recommended when finishing primary school. 

It is to be hoped that corruption will increasingly be seen as harmful and to be resisted in modern autocratic state structures.

Our caring mothers are, unfortunately. still waiting ...

A curious study on the relationship between pigeons' body weight and its effects on dominance should help us better explain the positive impact of Miobol.

Miobol Pigeon

What was the trial all about?

Group dominance hierarchies (rank, pecking order) were tested for stability over successive years using a closed population of captive homing pigeons.

It was also investigated whether a hierarchical structure (we will refer to it as "rank" for convenience) was directly related to body weight and, if so, whether this relationship was linear. In mathematics, this is called a function.

(It relates to two sets X and Y, where each element x (weight) from X has exactly one element y (rank) from Y).

If you plot these values on the xy axis of a graph and a line appears, this is called a linear relationship. Each rank corresponds to a weight.

The rankings were stable and correlated with body weight, but they could be quickly disrupted by artificially manipulating (increasing) it... 

Conversely, as soon as the weight was removed, the original rank order was restored just as quickly 


Many animals live and travel in groups. This has several advantages:

  • Increased vigilance, for example, against predators.
  • Saving energy by flying in the slipstream (" being in the wheel" for cyclists).
  • Increased foraging efficiency (searching for and finding food in the habitat), etc.

But there are also disadvantages. Within a group:

  • differences in personality
  • external features,
  • as well as physiology, create conflicts.

Such conflicts have likely led to the emergence of a rank order within the group through evolution.

Rank order thus benefits group members by, for example, reducing the incidence of physical conflict. Still, it can also result in some lower-ranking group members being denied access to resources (including food, territory, etc.).

A linear ranking order of precedence exists in a population of pigeons in a confined space that remains stable over time.

Here, we discuss a study showing that this stability can be disrupted by artificially adding weight to pigeons, usually in the bottom 50% of the hierarchy. These low-ranking pigeons immediately became more aggressive and moved up the order due to this weight loading (small lead blocks on their backs). 

However, this effect was only seen in the cocks and not in the hens. The hierarchy immediately returned to its previous structure after removing the artificial weight.

This disruption of stable rank implies a strong link between body weight and social behaviour, suggesting that an individual's personality can be altered by artificially manipulating body weight.


Seventeen pigeons were housed at the Royal Veterinary College (Hatfield, UK) (eight males, nine females). All the pigeons were six years old. They had been purchased when they were one year old. They were housed in a pigeon loft and had unrestricted access to food and water. During the study period, no pigeons were added to the group.

The pigeons were first studied at three different points in the annual cycle for three consecutive years to determine the ranking. Nineteen months after the start of the study, the nine pigeons that occupied the lowest positions in the rank order were artificially weighted with a lead weight. This weight was attached to the pigeons 4 hours before the start of the experiments using self-adhesive lead bicycle balance weights. The importance of the consequences was 5 g, and the artificially added extra body weight was 12 % of the weight of the pigeons. The value of 12% was chosen because it aligns with the natural variation in the body weight of pigeons during the annual cycle. The pigeons were familiar with the bio-logging devices attached to their backs from previous studies. The weights were removed immediately after the trials. The following rank assessment - without weights - occurred the day after the artificial weighting. The ranking was performed using calibrated protocols to assign an objective dominance score to each pigeon. Squeaking, chasing, beak grasping, neck pulling and flapping were the main behaviours measured.

Ranking within a group can benefit all members. It can reduce the severity and frequency of physical conflicts. Reducing the time spent on rivalry can be spent on other important behaviours such as maintaining plumage, vigilance and foraging. Ranks are often linear (directly proportional) within animal communities.

That is, higher-ranking individuals dominate all lower-ranking individuals. Linear hierarchies are typically linked to body weight or size. They are both stable and unstable over time: the extent of variation in rankings over time appears to be related to specific life history features, where groups of animals are either restricted to a particular area or live together for more extended periods (which tends to lead to stable hierarchies). For example, there were significant changes in the rank order of pigeons at the time of withdrawal from the group.

Does the ranking work differently when there are vast groups of pigeons (one loft races)?

Is ranking different in the air than on the ground? Look at the previous blog, where the leaders of a flock are replaced during the flight if they are not making good decisions...

Not to mention the catastrophic flights that led to a profound change in the group's composition.  

When extra weight was added (in green), the rank order changed significantly (Figure c) but remained linear (directly proportional); the rank order observed when nine pigeons were artificially weighted (a grey area) was very different from all seven unweighted rank orders. The rank order changed significantly when pigeons were artificially weighted. On average, the nine individuals whose weight was artificially manipulated had an increase in aggression, a significant increase in their rank. On average, the artificially weighted pigeons increased the number of aggressive behaviours: not all pigeons increased their aggressive behaviours.

The maximum decrease in aggressive behaviour observed in the artificial pigeons was 38.33%. (The maximum and minimum increases were 750% and 11.3% of the pigeons whose aggressive behaviour increased).

There was a significant interaction between sex and the amount of weight loaded. Rank was increased in cocks when extra weight was loaded. Hens loaded with additional weight did not differ from their unloaded counterparts in behaviour and subsequent rank measurements.

Adding weight resulted in an overall increase in aggression in the population; of the total number of aggressive interactions recorded, there was a stable relationship within rivalry relationships between weighted and non-weighted pigeons.

How dominance and body weight interact within and between seasons is not fully understood. In response to significant life history events such as breeding, moulting and (presumably) the racing season, body weight can vary significantly over the annual cycle. How these changes in body weight are reflected in the stability of the rank order and the position of individual pigeons within it is likely to significantly impact the overall dynamics of the group and the level of aggression.

Therefore, a better understanding of how (rapidly) rankings change with small, rapid changes in body weight has the potential to provide insights into both collective and individual energy use.

We can only conclude that a heavier cock is also more dominant and can therefore afford a privileged position.(E.g. easier access to food, partner...). Now that we know that more weight - a rounder, more enormous cock, for example - leads to a higher ranking, we can expect this to lead to better sporting performance.

The relationship between the mean body mass (graph above) and the mean rank for seven unweighted measures of the pecking order.

I spent a long time thinking about this survey.  I want to invite every fancier to do the same. It gives us a curious insight into the fundamental behaviour of our pigeons. Among other things, also the behaviour (in a loft race) when the group is (too) large for the efficient organisation of a ranking.

Is there a link between the effect of Miobol - which produces round, muscular pigeons - and the fact that the hens can undoubtedly take advantage of this phenomenon?


Could it be that a well-performing submissive cock becomes more dominant and surpasses itself (athletically) through a temporary increase in volume?

Indeed, consistent with the energy management performance model, body size measures (height and weight = "round pigeon") and resting metabolism positively correlate with rank.  As mentioned above, it is all in the function of saving energy. This is of crucial importance for endurance and recovery. We are privileged to be able to refine these findings.

In the meantime, Miobol, which supplies round pigeons, has become a permanent fixture in every feeding schedule throughout the year

Miobol Pigeon

Very particular …

Similarly, a phenomenon we cannot fully explain is the significantly earlier weaning (at least one week) after using Miobol.

Is it better for temporarily dominant parents
To wean their offspring?


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