What's in a date?
While there are many factors that impact the rise of a top players, recent evidence suggests that success is influenced by birth date.
There are many factors that impact the development of a top level sportsperson. Success is most commonly considered to be based upon a combination of talent and hard work. Remarkably, while these factors are undoubtedly important, recent evidence suggests that success is also influenced by birth date.
In the mid-1980's a Canadian psychologist named Roger Barnsley observed that in the National Hockey League and Canada's top two junior hockey leagues there was a strong relationship between the month in which a player was born and their chances of playing top tier hockey. In the two junior leagues there were approximately four times more players born in the first quarter of the year (January to March) than the last quarter (October to December).
The reason behind this is that at age group level, there is a 12 month spectrum from which players are selected from. This means that player 'A' born in early January will be in the same age group as player 'B' who is born in late December.
At the first stages of representative selection when children are starting at school (or in some cases even earlier), near on a year can make a tremendous difference in their physical characteristics. At an early stage it is often the bigger, stronger players who appear to have the most potential, with physical traits masking differences in talent.
Once a player is selected at the first stage they receive certain benefits: better coaching, more training time and better competition from their team-mates and opposition. Conversely, a player that did not originally make the cut is not gifted such luxuries and so it becomes harder for him to keep up with the development of those who made the cut originally.
Coined as the 'Matthew Effect' by sociologist Robert Merton, based on the bible verse: “For everyone who has will be given more, and he will have an abundance. Whoever does not have, even what he has well be taken from him” (Matthew 25:29), the application of the theory to sports teams makes for interesting reading.
With the IRB Junior World Championships underway, we at Planet Rugby thought we would test the theory and analysing the squads from South Africa, New Zealand and Australia where January 1 is the traditional age group cut-off the following can be found:
Total number of players: 78
Number of players born from January-June: 53
Number of players born from July-December: 25
That means that 68% of players from those three squads were born in the first half of the year, which is a substantial figure on its own but looking at the two ends of the spectrum the figures are even greater.
Total number of players: 78
Number of players born in January: 14
Number of players born in December: 1
That means that nearly three times more competitors were born in the first three months of the year than in the final three – incredible.
This is no once off occurrence either. The following are the age distribution statistics from the New Zealand U20 teams from the past four years:
Total number of players: 84
Number of players born from January-June: 55
Number of players born from July-December: 29
Of those 84 players, nearly 18% were born in January. An even distribution would see 10.8% of players born in each month.
While data on the exact distribution of births across each month for this period in New Zealand are not available, studies in Europe show that there is no trend showing a significantly increased number of births in any one month.
Of course this is only a trend; you will always have outliers, sometimes players with exceptional talent and discipline can overcome this. Take for instance three-time IRB Player of the Year, Richie McCaw. Born on December 31, McCaw was from the outset at a great disadvantage, but when you're that good nothing is going to stop you!
By Julia Harris