It’s just not fair. There I was, a freshly produced sand tiger shark embryo, developing nicely and making my way down the ovarian ducts to one horn of the uterus. I had blastulated like a boss, totally owned gastrulation and even did a half decent impersonation of ontogeny recapitulating phylogeny. Things were looking good. Head: one, at opposite end to tail – check. Fins, paired appropriately on the bottom, tandem along the top – check. Gills – check. Teeth – check. Aww yeah, now we’re cooking. Those menhaden aren’t going to know what hit ‘em. Yessiree bob, I am one bad motor scooter. I’m cruising along, feeling fine, make a quick right turn into the uterus and then BAM! Totally nailed by another sand tiger embryo! Right. In. The. Face. I’m like “Where’d YOU come from” and he was like “You didn’t think your dad was the ONLY one nailing yo Mama did you? Oh wait, she’s my Mama too. Well never mind, you get the point. This here uterus is MINE” And I was like “Yeah man, but don’t taste me bro!” and he was like “Can’t talk…eating”. And then things went kinda dark. What’s up with that?
Awwww, fall prey to a little intra-uterine predation did we? Dear me, how sad. Want me to put an Elmo band-aid on your dismembered corpse? Welcome to the big leagues kid, sucks to be you. News flash – life ain’t fair and you are not a winner just for showing up. In fact, a lot of the time you don’t even GET to show up. Did you think this would be like Glee, that they would allow you all to reach the peak of your pubescent glory before everybody holds hands and sings a bunch of songs that they are way to young to possibly remember? Er, no. Sorry bub. Sometimes the war is over before it even begins. Nature red in tooth and claw doesn’t start at birth, it starts BEFORE birth and you, my friend, just got schooled. Why did this happen you ask? Well, you see your Mum…hmmmm, how do I say this? She get’s around. Crazy for claspers, capisce? Your Dad? Nothing special, one of many. That means your fallopian flat mates are your half siblings at best, which in turn means most of them, from a selective perspective, have a vested interest in seeing you dead. But wait, there’s more – they also get to cannibalistically derive sustenance by eating your puny (but ever so soft and tasty) little body. No, the sand tiger uterus is not like Glee, it’s more like The Highlander (or for you Gleeker-types: The Hunger Games): it’s not uter-US, it’s uter-ME, and there can be, only ONE! Only one pup – presumably the fittest – and only one dad. If it helps, try to think of your pathetic existence as having served a useful purpose, as an important cog in the great process of natural selection. That’s total BS, but maybe you’ll quit bugging me with your blubbery sob story.
Inspiration – Dr. Craig, my wife and:
Demian D. Chapman, Sabine P. Wintner, Debra L. Abercrombie, Jimiane Ashe, Andrea M. Bernard, Mahmood S. Shivji and Kevin A. Feldheim. (2013) The behavioural and genetic mating system of the sand tiger shark, Carcharias taurus, an intrauterine cannibal. Biology Letters. 9(3): 20130003 doi:10.1098/rsbl.2013.0003
PS – After I wrote this, I found this, which prompted me to append this: