On Shore Leave, He Only Had Eyes _ Big, Baleful Eyes _ for Her
Jul. 02, 1995
WASHINGTON (AP) _ Fate had driven them apart but seven years later, they found each other again, on the same windblown Scottish isle where they had met. He could have played the field. But, no. He wanted her.
No one would have expected it from such a slippery character. He's part of that seagoing breed that comes ashore, gets into fights, makes off with a doe-eyed partner and dumps her like a rock.
But the story of S2 and J8 _ two gray seals _ may challenge the conventional wisdom about polygamy among mammals.
Until now, humans have been regarded as one of the few arguably monogamous mammal species, however lousy some may be at it. Now a study contends seals are big on fidelity, too.
British researchers, in a study published in the journal Science, concluded ``many pairs of seals establish durable ties, recognizing each other between (mating) seasons and coordinating their behaviors.''
The research team, led by Bill Amos of the University of Cambridge, used genetic analysis and field study to monitor breeding among 85 males and 88 females on North Rona, a small, cliff-bound island off northern Scotland.
DNA tests revealed many seal pups from the same mothers were full siblings, having the same fathers, despite all that stands in the way of the same two seals meeting each year during brief forays ashore to mating grounds.
``This result cannot be explained by mating patterns based solely on male dominance and ... the organization of the breeding colony,'' the study says.
Many seals ``mate preferentially with previous partners.''
Amos, by phone from Cambridge, said the findings add a new dimension to the mating game observed among many animals in which the most aggressive males establish dominance over others and impregnate a multitude of females.
In this case, fidelity after the initial mating meant less aggression and, possibly, fewer pups being squashed by fighting males.
Seals mate again shortly after giving birth _ during the same shore leave, so to speak _ so colonies are full of vulnerable young during the angry macho rituals of courtship.
Amos said it's as if the female is saying to her previous partner, ``Right, I'm having you, you produced a good pup last year. Go away, everybody else. Game's over.''
Gray seals have long been regarded as polygamous, and Amos said that trait coexists with fidelity in the same colony. The strongest of the strong do compete for females and win.
But he said the findings may help explain how the less strong find mates and why the females may be attracted to them.
Although female seals rarely solicit partners, they frequently reject male advances.
Not so with J8, in her encounter with S2 on a part of the island remote from where he had fathered her pup seven years earlier. Females outnumbered males seven-to-one, so S2 had plenty of choices. But there they were.
``Nice little romantic story,'' Amos said.
They did not run together in slow motion along the beach, however. Amos said it was more like ``gallumphing.''