Explaining why so many world class athletes manage to come from such a limited area, and limited number of people, in Kenya has become the subject of lifetimes of academic study.
But ahead of this week's first World Cross Country to be staged in the country that has so dominated this section of the sport over the past two decades, it might be of some practical use, or interest, to understand many of the runners' naming conventions.
John Manners - Kenyarunners.com - a self-confessed fan of Kenyan runners, puts it this way:
Traditional Kalenjin names are commonly drawn from a stock of just a few dozen, both first names and surnames from the same limited inventory. A son takes his surname from his father, as in the West, but the name he takes is the fathers first name.
Typically, a child is given a name at birth that relates to the circumstances of the birth. A boy's name usually starts with the prefix Kip, a girls with Che or Chep. Thus, for example, a boy born at dawn may be Kipkoech; one born at sunset, Kiplagat; born outdoors, Kipsang; born during a drought, Kipkemei, and so on. A few months after birth, the child will be given an ancestral name, used only by close relatives, and these days most children are given a biblical name as well.
When a boy is circumcised and initiated into adulthood at about age 15, he takes his surname, which is commonly the father's first name, minus the Kip. But a boy can choose any of his father's first names -- the birth name, the ancestral name or a nickname -- and brothers often try to distinguish themselves by selecting different last names.
Institutions such as schools and the armed forces may further complicate matters by paying no heed to Kalenjin custom and tagging a young man with just his biblical name and first name, dropping the surname. And lately, some young men and many young women have begun to adopt their father's surnames, Western style. Thus Kipchoge Keino's sons call themselves Keino, rather than Choge, as tradition would require.
The Kalenjin pay no more attention to the meanings of their names than the British do to the import of Brown, Smith or Livingstone, but the meanings give clues to what matters in Kalenjin society, and knowing a few may help muddled athletics fans remember who is who.
Steven Downes for the IAAF
Common birth names
Kipkorir--born shortly before dawn
Kipkoech--born at dawn
Kimutai--born in mid-morning
Kibet--born at midday
Kiplagat (Kiplangat)--born at sunset
Kipkirui--born shortly after dark
Kipkemboi--born at night
Kipngetich--born when cows are taken to pasture after morning milking
Kiprotich--born when cattle are brought home for evening milking
Kipngeno--born when goats are waking up
Kiprono--born when sheep or goats are brought into the house in the evening
Kipkeino--born when sheep or goats are being milked (i.e. when cows milk is short)
Kiplimo--born among grazing cattle
Kipngeny--born when cattle are at a salt lick
Kipkosgei--born after a long labor, or a long interval between children
Kipchirchir--born in a hurry, after short labor
Kiptanui--fainted, failed to cry or breathe at birth
Kipketer--born on the verandah
Kipchoge--born near the grain storage bin
Kipkurgat--born by the door
Kibitok--born on the fathers side of the hut, not the mothers
Kiptoo--born when visitors are around
Kiptum--born during circumcision ceremonies
Kimaiyo--born when beer is being brewed or drunk
Komen--born when beer is being brewed or drunk
Kipruto--born away from home, on safari
Kipchumba--born near white men, i.e. in a hospital, in a town, on a white-owned farm
Kipkemei--born during a drought
Kiprugut--born during a famine
Kiptalam--born during an infestation of locusts
Kipsigei--born on his own (i.e. the mother had no help)
Cheruiyot (male only)--born when everyone was asleep
Kitur--born after parents had begun to despair of having a child
Kigen--a long-awaited son (usually born after several daughters)
A few nicknames
Tergat--one who stands or walks with his head bent to one side
Barmasai--one who killed or captured a Masai
Barsosio--one who captured a supply of a prized plant