Surprises.

A friend of mine sent me a newspaper clipping and asked “What the heck is going on here?”  Entitled “ ‘ Porpoisidal’ Dolphins,” the article quotes some marine mammal researchers who witnessed “violent and fatal” attacks by bottlenose dolphins on harbor porpoises.  They were baffled that one marine mammal would attack and kill others not likely to be direct competitors, but they speculated that high levels of testosterone might have been involved.

It’s challenging to evaluate such reports because of our human perspectives.  We shake our heads at human gang-rapes and shooting sprees, somewhat comforted that these are aberrations even among humans.  We accept the range of human variability without recognizing anything similar among other animals.  Then some researchers discover panicidal (murderous) chimps or individual baboons that stalk and kill young antelope.  Then there is Fifi, behaving just fine at home but becoming a raging pack animal out to kill when running loose with other “domestic” dogs.  These are perhaps the flip side of cases where the lion lies down with the lamb, where the tiger mother raises piglets or the she-wolf raises a feral boy.  You can advance hypotheses about the overwhelming strength of maternal instincts or the corrupting influence of testosterone; some may prove true, others not.  The interesting thing is that we are surprised.     Continue reading →