We humans do weird stuff as parents, but we keep good company. Animals the world over have some fascinating ways to cope with raising babies, and some of those practices prove shocking.
We'll encounter a few parental systems that humans might envy, like having 24-hour babysitters or selfless dads who will travel miles to give baby much-needed water every day. Other parenting behaviors are a little less endearing. From neglect to straight-up infanticide, you'll be reminded that nonhuman animal parents aren't trying to get their kids into the best preschool; they're just trying to ensure survival.
So grab your judgey parenting hat, and let's start with some surprisingly sweet pachyderms.
As we'll see in the upcoming pages, a lot of the "surprising" things animals do with their babies would seem psychotic to humans. But leave it to elephants to develop a practice that isn't so much surprisingly strange as surprisingly kind. Turns out that just like the ponytailed girl across the street, young female elephants act as babysitters (or supplemental maternal support) to young calves.
While most female elephants will protect and nurture any calf in the herd, young females who haven't yet reproduced are most keen to act as a mother figure to the baby elephants. Called allomothers, this role is beneficial to everyone involved: Moms may feed longer and produce a better milk supply, while youngsters receive protection and guidance. The allomothers get a little parenting practice before they themselves start reproducing [source: Fishlock].
Earwigs Sniff Out Best Babies
Perhaps you remember your mother lovingly telling you and your siblings that she had no favorites and loved you all equally. Little did you know you really dodged a bullet by being born to a human mother and not a coldhearted, shrewd earwig mom.
In earwig nation, the idea of unconditional maternal love isn't a given. When earwig mothers have a clutch of babies (or nymphs), the mothers will sniff out a chemical signal from the healthier ones and proceed to provide more abundant care and feeding to those babies. The babies that are identified as hungrier and less robust will be given less attentive parenting and feeding [source: Gill].
So is this strange animal behavior nothing more than cold cruelty? Scientists point out that there are some really compelling reasons that earwig moms zero in on healthier nymphs. One, they have a lot of babies (30-60 at a time), so mortality is unavoidable. And naturally, focusing their efforts on more viable offspring makes a lot of sense -- no matter how nasty it might seem to the hungry earwig nymph.
Seahorse Dads Give Birth
We now turn our attention to one of the most well-known species that leaves the business of being born to males: the seahorse, also known as the ocean's perennial "Daddy of the Year." Sort of.
Male seahorses do a decent job of collecting up to 2,000 eggs from a female during an underwater mating dance and fertilizing them. When the little eggs hatch, he even keeps them in his pouch until they're accustomed to the sea's salinity. And yup, he gives birth to them through muscular contractions [source: Danielson].
But we can't claim male seahorses are terribly effective father figures, since they take off as soon as the little ones are born, without ever catching a Little League game and missing every piano recital.
Sandgrouse Kids Drive Dads to Drink
When we talk about weird things animals do, it's tempting to just point out the more blatantly bizarre, like the mothers who eat their young or the fish who only keep offspring from attractive partners. (Don't worry, they're coming up in our list.) But we shouldn't forget that animals do lots of strange things for their children that, in reality, are borderline-heroic.
Consider the sandgrouse. A resident of southern Africa's arid zones, this pretty little bird often has to travel miles at a time for water. What to do when you have a nest full of babies who aren't ready to fly?
The male sandgrouse to the rescue! Although he incubates the babies at night when mom seeks food, in the day he's free to travel to watering holes. He proceeds to wade in and get a good soak. His special, coiled feathers uncurl and trap water through capillary action. When he flies back to the nest, the little ones nestle up to his belly and get their gulps of water in for the day from his wet feathers [source: Lloyd]. Dad quickly takes a dust bath to rid himself of the strong scent of wet feathers that could attract hungry prey.
Panda Moms Have One Child Policy
Pandas have an excellent publicity machine. They're so cute! They're so lazy! They're so endangered! (So it's not all terrific, but at least they're getting attention.)
But one thing that Panda Corp. has hidden from you? The fact that Mama Panda is a coldhearted, favorite-choosing shrew of a parent. Or a little less dramatically: Mama Panda will often give birth to two babies but almost always only raises one [source: Angier].
While this may seem shockingly callous to baby-loving (not to mention panda-loving) humans, you have to remember that raising babies in the wild -- even super adorable, cuddly ones -- is not easy. Panda moms have to expend an enormous amount of energy to even digest their own food, and providing milk or resources for little ones is extremely difficult [source: Buchen]. By concentrating their energy on one of the babies, the chance of having one healthy offspring seems better than having two weak progeny.
Pipefish Dads Choose to Provide Based on Mom's Looks
Like our friends the seahorses, pipefish leave gestation and birthing to the males, after females leave their eggs in a male's pouch. But researchers were curious -- do male gestational carriers have some of the same tricks that females use for more robust offspring? (Like a female who mates with more than one male but only uses the biggest male's sperm.)
Turns out, male pipefish can play that game too. Male pipefish were bred with one less "attractive" and one more "attractive" female (attractive meaning bigger, in pipefish parlance). Male pipefish ended up withholding resources from embryos if they were from the less attractive mate. They also provided more robustly when they were carrying eggs from the more attractive pipefish partner [source: Paczolt and Jones]. Subsequently, more embryos survived -- and were healthier -- when the male bred with the more attractive female [source: Fountain].
Now, let's not look down our nose at the pipefish. Sure, we might be less obvious about it, but the fact remains that some of us would feel a lot better about carrying the baby of the cute One Direction boy than we would about that of some Joe Schmo from off the street. He's adorable!
Eagles Parents Totally Fine With Raising Cain
In human relationships, sibling rivalry usually takes the form of stealing toys or setting up imaginary lines no one can cross. Parents might not want to be dragged into these scuffles, but they'll usually referee the proceedings if they devolve into actual violence. Not so with our raptor friends, who may let one baby actually kill another.
Granted: I hate birds. So perhaps the behavior isn't as unduly harsh as I claim. It's commonly seen in eagles (both golden and black, although it's not unknown in bald), and it's usually a matter of the firstborn chick fighting for -- or even just receiving -- the most food and resources from mom [source: Ehrlich et al.]. However, sometimes the bigger baby actually will peck to death the little one, as Mother Bird casually watches [source: National Geographic]. Because birds are nuts.
Or, I will grudgingly admit, because Mother Bird knows just as well as Baby Bird that there's just not enough resources to go around, and the strongest will survive. As the youngest (and absurdly smallest) in a family of all (burly) males, I for one am very grateful this parenting trait never got to surprise me firsthand.
Cotton-top Tamarins Parent Cooperatively
It's impossible to resist an animal that has hair resembling Doc Brown in "Back to the Future," and cotton-top tamarins are no exception. Cute primate appearance aside, these fluffy tamarins also are surprisingly adept at parenting.
In fact, tamarins parent cooperatively, meaning that there is no primary caregiver. All the males and females in a social group provide resources and food for the tamarin babies. And it is babies, plural: Cotton-top tamarins have twins more often than single babies, and it's not easy to carry both little ones at a time. Besides the first week of life when the babies must nurse constantly, other group members are just as responsible as the mother for taking care of the little ones [source: Lang].
It helps that only one female at a time is reproducing, so everyone can chip in to help. But this in itself is another surprising thing that animals do with their kids: It seems that the dominant female in cotton-top tamarin groups will suppress reproduction in other females to ensure only one pregnancy at a time. Keep in mind that the other females are often her daughters, thus keeping her superiority as a dominant mom intact.
Long-tailed Skinks Eat Their Own Eggs
We have no shortage of stories about infanticide in nature. Most of us who have been in a fourth-grade classroom know that hamsters are one of the most well-known creatures to devour their young, along with mice and other rodents. (And that's probably a fear response, or a survival technique to cull the herd for a stronger, smaller brood [source: National Geographic].)
But long-tailed skinks that inhabit the island of Lanyu (just off the coast of Taiwan) exhibit a few parenting traits that aren't just surprising to humans, but out-of-the-norm for reptiles in general. First off, the females don't just lay their eggs and bolt, like many lizards. Instead, they stick around to protect the nest of eggs.
Super nice, right? Well, not so fast. Because these skink moms have another unusual parenting trait not commonly seen in lizards. If they feel they're threatened by predators, the skinks immediately gobble up their own eggs [source: Taipei Times]. While this would strike most of us as terribly cold-blooded -- even for an ectothermic lizard -- it's actually a pretty reasonable way for Mom to consume more calories in an effort to create a future successful reproduction.
Human Parents Do Weird Stuff, Too
Feeling pretty smug, aren't we? Sure, we humans can be fairly confident that we won't eat our eggs if a snake ambles by, but we're not immune to surprising parenting decisions.
It's easy to point out the strange, like premastication, or prechewing food before handing it over to an infant to finish. While a lot of people might be horrified (or at the very least, compelled to roll their eyes) at the practice, some researchers argue that it's a good way to introduce babies to solid foods and provide better nutrition to kids [source: Hanes].
But what about the cool things humans do as parents? For one, there's our identically strong parental bond with nonbiological children, adopted or foster. And let's not forget that most animals don't have a bond with dad at all; only 3 to 5 percent of mammals show paternal investment [source: Geary and Flinn].
So it might be worth it to spend a minute or two contemplating how we as humans have evolved to take care of children, and give all animals a break. After all, we're doing our best.
HowStuffWorks takes a look at gastroliths, or 'stomach stones' and why some animals eat them.
Author's Note: 10 Surprising Things Animals Do With Their Babies
So I guess if I had to raise my child in a community with animals, I'll be sticking with elephants or cotton-top tamarins. I sure like the idea of having young females around all the time who want to teach my kid how to survive (takes the pressure of potty training), and it'd be fantastic to have a group of primates willing to shoulder the kid (literally) when I couldn't. And let's be honest: I'm a little afraid I wouldn't pass the male pipefish's test for an attractive mate.
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