Motherhood in the wild-not what you thought
I just thought this was interesting (also very sad):
One Thing They Aren't: Maternal
By NATALIE ANGIER
Published: May 9, 2006
Oh, mothers! Dear noble, selfless, tender and ferocious defenders of progeny all across nature's phylogeny: How well you deserve our admiration as Mother's Day draws near, and how photogenically you grace the greeting cards that we thrifty offspring will send in lieu of a proper gift.
ABANDONMENT | PANDA
Cute? You think so. But this mother gave birth to two cubs and when one of them thrived, she left the "spare" behind without a backward look.
Here is a mother guinea hen, trailed by a dozen cotton-ball chicks. Here a mother panda and a baby panda share a stalk of bamboo, while over there, a great black eagle dam carries food to her waiting young. We love you, Mom, you're our port in the storm. You alone help clip Mother Nature's bloodstained claws.
But wait. That guinea hen is walking awfully fast. In fact, her brood cannot quite keep up with her, and by the end of the day, whoops, only two chicks still straggle behind. And the mama panda, did she not give birth to twins? So why did just one little panda emerge from her den? As for the African black eagle, her nest is less a Hallmark poem than an Edgar Allan Poe. The mother has gathered prey in abundance, and has hyrax carcasses to spare. Yet she feeds only one of her two eaglets, then stands by looking bored as the fattened bird repeatedly pecks its starving sibling to death.
What is wrong with these coldhearted mothers, to give life then carelessly toss it away? Are they freaks or diseased or unnatural? Cackling mad like Piper Laurie in "Carrie"?
In a word — ha. As much as we may like to believe that mother animals are designed to nurture and protect their young, to fight to the death, if need be, to keep their offspring alive, in fact, nature abounds with mothers that defy the standard maternal script in a raft of macabre ways. There are mothers that zestily eat their young and mothers that drink their young's blood. Mothers that pit one young against the other in a fight to the death and mothers that raise one set of their babies on the flesh of their siblings.
Among several mammals, including lions, mice and monkeys, females will either spontaneously abort their fetuses or abandon their newborns when times prove rocky or a new male swaggers into town.
Other mothers, like pandas, practice a postnatal form of family planning, giving birth to what may be thought of as an heir and a spare, and then, when the heir fares well, walking away from the spare with nary a fare-thee-well.
"Pandas frequently give birth to twins, but they virtually never raise two babies," said Scott Forbes, a professor of biology at the University of Winnipeg. "This is the dark side of pandas, that they have two and throw one away."
It is also something that zoos with ever-popular panda displays rarely discuss.
"They consider it bad P.R. for the pandas," Dr. Forbes said.
Researchers long viewed infanticide and similar acts of maternal skulduggery as pathological, a result of the mother's being under extreme stress. A farmer's child pokes around in a rabbit's nest, for example, and the mother rabbit responds by methodically consuming every one of her eight baby bunnies. By standard reckoning, it made little genetic sense for a mother to destroy her young, and maternal nurturing was assumed to be a hard-wired affair.
More recently, scientists have accrued abundant evidence that "bad" mothering is common in nature and that it is often a centerpiece of the reproductive game plan.
In the blockbuster movie "The March of the Penguins," the emperor penguins were portrayed as fairy parents, loving every egg they laid and mourning every egg that cracked before its time. Among the less storied royal penguins, a mother lays two eggs each breeding season, the second 60 percent larger than the first. Just before the second egg is laid, the mother unsentimentally rolls the first egg right out of the nest.
In Magellanic penguins, the mother also lays two eggs and allows both to hatch; only then does she begin to discriminate. Of the fish she brings to the nest, she gives 90 percent to the larger chick, even as the smaller one howls for food. In the pitiless cold of Antarctica, the underfed bird invariably dies.
Like penguins, many species that habitually jettison a portion of their progeny live in harsh or uncertain environments, where young are easily lost and it pays to have a backup. At the same time, the harshness and uncertainty make it virtually impossible for a mother to raise multiples, so if the primary survives, the backup must go. Sometimes the mother does the dirty work herself. More often, she leaves it to her preferred young to dispatch of its understudy.