It’s not at all surprising, Expat. For the same reason a mare would reject a donkey (if given a choice) members of species are instructed what to do by their genes; that is, if a female devotes an egg, the time and resources to raise an offspring, here a calf, the product of mating with a member of a different species, then like the product of the pairing of a female horse and a donkey, the result might be a sterile offspring, as with the mule.
Consequently their genes are not propagated, so that the females who choose to be `open-minded’ produce no offspring with similar genes. The successful elephants went with a sure thing: a male they recognize as being of their own kind.
Fuzzy Wuzzy
Was a bear.
Fuzzy Wuzzy,
Had no hair.
Fuzzy Wuzzy,
Wasn’t fuzzy,
Was he?
The last line of that “poem” I’ve always seen is...
“Fuzzy Wuzzy really wasn’t very fuzzy wuzzy was he”
Makes sense. Thanks!