Gestating and rearing a tiny human is a lot of work, and it can be hard not to look with a touch of jealousy at a mouse's 21-day pregnancy, or the few months it takes for a puppy to achieve independence from his mother. But don't feel too badly about it: there are a lot of very good reasons in the animal kingdom to be glad you're a human parent to a human baby instead of the alternative.
1. Conception - Marine Flatworms
Being pregnant comes along with swollen ankles, backaches, lifestyle restrictions, and a horde of strangers thinking it's totally cool to come grope your belly. But what if you could inflict all of that on your partner instead of yourself? Hermaphroditic marine flatworms have taken the battle of the sexes to hilarious extremes: two flatworms will duel each other until one wins by stabbing the other one with a load of sperm. This behavior is called 'penis fencing' by scientists, because as it turns out scientists aren't any more mature than the rest of us. Personally, I like the 50-50 shot at avoiding having to be personally responsible for gestation, but I'm not too keen on the potential for pregnancy via stabbing. I'm happy to be stuck with stretch marks and enormous clown feet instead.
Fun fact: the white pointy things in the above picture are the flatworm's penises. (Penii?) So if your boss is really into invertebrates, this article might technically be NSFW.
2. Post-Baby Body - Suriname Toad
During her toad-on-toad sexytimes, the Suriname toad's eggs become embedded in her back, where they stay as they hatch into tadpoles. Most frogs and toads are living solo by this point, but not the Suriname toad's offspring: they continuing to occupy Mom's back skin as they continue to develop into miniature toads. I assume that the young toads eventually return to their mother's back after graduating college until they find steady amphibian work. I have a post-pregnancy perma-pooch of belly skin that's never going away, but on the bright side, I don't have a toddler-sized saggy empty skin-bag hanging off of my back. #winning
3. High-Needs Baby - Cuckoo Bird
See that mama and baby bird up there? Take another look. The tiny little brown bird is the adult, a warbler; the enormous pudge-monster on the left is a baby cuckoo bird. Cuckoo eggs are laid in warblers' nests by female cuckoos, who are the ultimate in hands-off parents. They leave their babies to be raised by the warblers, who, as birds, aren't well equipped to call the hospital to ask about possible mix-ups in the nursery. Another thing they aren't well equipped to do is feed a baby bird who is pretty quickly going to dwarf them. Every time the cuckoo baby opens up its giant gaping maw to squawk for more food, it hits the switch in the warbler's brain that says, "Oh shit, did I forget to feed the kid?!" Sometimes I feel like it's hard to make enough dinner to satisfy my one-year-olds, but at least they're not fully double my size.
4. Spitting Up - Fulmars
If you had a baby with a sensitive stomach, you are intimately familiar with that certain old-cheese odor. But on the bright side, at least your baby wasn't a fulmar bird. The word 'fulmar' means 'foul gull', and this creature earned its name with its disgusting defense mechanism. When threatened, a young fulmar can spew oil from its stomach, specially crafted to be spectacularly putrid by thousands and thousands of years of evolution. The oil is made of wax esters, which you may know better as 'that stuff that makes fish smell fishy'. I will take my child smelling like stale milk over fish-barf any day.
Note: do not watch the linked video that image came from unless you want to watch lovingly-filmed slo-mo footage of a vomiting bird. Conversely, if, like me, you'll watch it three times in a row while laughing hysterically, have at it.
5. Sibling Rivalry - Sand Tiger Sharks
Each of my kid's favorite toy is 'the toy that my sibling is currently playing with', and they enjoy re-enacting the stampede scene from The Lion King, where one of them plays the wildebeest horde and the other plays Simba. However, they have nothing on tiger shark babies, since both of my kids survived a shared gestation. Tiger shark fetuses will actually kill and eat each other in a bid to win this super-creepy intrauterine Survivor-style gestation.