麻豆传媒

THE authors of Strange Bedfellows are married to each other 鈥� happily, they assure us. They have also 鈥渃hosen to be monogamous鈥� and this, according to and , is a personal decision, not a response to 鈥渢he sanctimonious and often hypocritical preaching from rightwing-nut ayatollahs, nor as genuflection to current Western social tradition and expectations鈥�.

I鈥檓 always glad when people avoid the wing-nut path, but I hadn鈥檛 realised that fidelity was so fraught with political ramifications. I wish I鈥檇 known what a hero I was being when I chose the monogamy route. (Note to self: use this to my advantage when next arguing with husband.)

The authors鈥� real point is that monogamy is not only a deliberate choice, but a difficult one. Nature favours sexual variety as a reproductive strategy: of the world鈥檚 mammal species, 98 per cent or more are polygamous. Of the remaining few, most are what scientists call serial monogamists: they exchange partners, they cheat and they try to conceal their extra-pair copulations (EPCs). In other words, they are like us. 鈥淥ur species is 鈥榥aturally鈥� resistant to monogamy,鈥� the authors write.

鈥淥f the few monogamous species, most exchange partners, cheat and conceal their affairs鈥�

It鈥檚 worth noting that most scientists don鈥檛 equate biological monogamy with pure fidelity, but with partnership. Males and females in strongly monogamous species tend to be near identical in size and appearance. They need to be well matched. They do equal work when it comes to raising their young, hunting for food and defending the nest. Most bird species are considered monogamous in this physically matched way. But birds occasionally choose the EPC route if it improves reproductive success: researchers who gave male blackbirds vasectomies found that their long-time partners continued to happily lay eggs after the surgeries.

Barash and Lipton covered this territory in their previous book, (W.H. Freeman, 2001). In contrast, they describe Strange Bedfellows as dwelling less on obstacles to partnership, and more on what we can learn from nature鈥檚 rare but successful monogamists.

I too believe we can learn a lot from the behaviour of other animals, but using it for relationship advice seems like a bit of a stretch. I marvel at beavers鈥� pragmatic monogamy, as they work in tandem on their engineering projects. But nothing my husband could say or do would persuade me to gnaw on a tree. And while I am intrigued by the fact that testosterone levels drop in committed pygmy marmoset males, making them unusually sweet-natured monkeys, I don鈥檛 think that would sell most men on marriage.

Perhaps the authors recognise this because far too often the recommendations resemble homilies 鈥� 鈥渕onogamy, if it is to last, must be for all seasons鈥� 鈥� and the book, however fascinating the facts, feels like an effort to make too much out of too little.

Still, I enjoyed speculating on cross-species relationship advice. My favourite possibility came from the female Peruvian warbling ant-bird, who keeps her mate firmly in check. If he starts singing to another female, she squawks until she ruins the mood. I considered belting out a song to keep my husband鈥檚 attention at our next party 鈥� I鈥檓 just not sure it鈥檚 the kind of attention I want. (Note to self: learn to carry a tune, just in case.)