Do elephants puke?

This is the brief story about how and why I spent four hours trying to figure out if elephants could puke.

First, the answer: Yes, it appears that they can, and it has been observed. It seems, however, to be extremely rare. Which is probably good. Elephants eat a lot so that would be a LOT of stuff coming up. And imagine if it came out your nose when your nose is two meters long. I shudder in sympathy.

Anyway, why did I spend any time at all figuring out if elephants could puke? Well it's because I made a joke in my book. One single joke. I was writing about elephant repellant (I have smelled it, it is repellant. Not the worst thing I've ever smelled but certainly in the top 10), and mentioned that when they smelled it, the elephant would gag and leave.

But would they gag? COULD elephants gag? I had to know. I went on a fact hunt.

It turns out relatively few people have asked themselves whether elephants could barf, let alone gag. At first glance, you'd think of course an elephant could upchuck. You can, right? The systems can't be that dissimilar.

Taxonomically speaking, there's not actually much reason to believe elephants can toss cookies. Both humans and elephants are eutheria. Some eutheria can puke. Humans, pigs, dogs. Some can't. Rodents (with the exception of rabbits) are a prime example (and why it can be hard to poison rats! They can't puke and so they rely heavily on a very good sense of smell to know whether something is safe to eat. Once they eat, there's no going back. So poisons have to be awfully tasty. It's a constant challenge).

Elephants are most closely related to the Perissodactyla, which is the group with horses. Horses cannot vomit. Their sphincters squeeze so tightly nothing is coming back up (which, as someone who suffers from a lot of heartburn, makes me intensely jealous).

If a horse can't vomit, and they're most closely related to elephants, well then maybe elephants can't either? Well, maybe, but. A 2011 review "The translational value of rodent gastrointestinal functions: A cautionary tale" has a figure which is officially among my favorite scientific figures (I have a lot of favorites). Figure 3 is a full phylogenetic tree, which each animal noted by whether it hasn't or doesn't have a profession upchuck system. Scientists after my own heart. In THIS, the horses AND the elephants (Proboscida) are both listed as being able to hurl. This is based on the presence of functional motilin and ghrelin systems, which are involved in gut activity. Basically, these two systems push stuff down, and can also, if needed push things back up.

So, according all equine lit you'll ever read, horses can't hurl because while their gut systems say they should, their sphincters say no. But according to gut motility, they should be able to, and no sphinchter is a perfect seal. It's just apparently really rare.

Now we get to elephants. No one has ever seen a splash of elephantine puke on the plains of Africa that has told scientific literature about it. But there IS a case report of a captive elephant that DID throw up this one time.

The elephant CAN puke. Which presumes that it can gag. You are welcome.

Why did I go down what turned out to be a four hour rabbit hole? Well in part because it was fun! But also because if I hadn't, my fact-checker would have been after me, asking whether or not it was true.

It might surprise you to know that you can't necessarily always trust everything you read in books. Many books are not, especially older ones! I've written about this before. This is not because writers are out to be evil and tell lies. No, it's because hiring an independent fact checker is expensive, and the publisher isn't paying for it. Now, fact checkers are becoming more common. This is partially because of a new high profile embarrassments. It's also because, where we can, most of us WANT to hire fact checkers. We know we might miss things, make mistakes, mix up pdfs or anything else. We want to tell the truth, we want to know that what we're saying is backed up by science, history, or anything else.

But there are still some people out there who are, er, not so conscientious. Ahem. So how do you know? Here are some things to look for:

• When you get a book, flip to the acknowledgements. Is a fact checker thanked? Good sign!

• Check for notes! A good nonfiction book that isn't a memoir may well have pages and pages of notes, each with a citation. Those are good!

• Check for sources within the book itself. Does the author cite a paper? A scientist or historian by name? "Scientists say" is not sufficient, and "it's common wisdom that" is definitely no good.

Finally, if you get fooled, if you end up realizing a book you loved has no notes and merely feels truthful, or ends up on If Books Could Kill, be gentle on yourself. We have ALL been fooled before, and we'll all be fooled again. It's why we hire fact checkers.

And don't worry, I'm pretty sure elephants can puke if they have to.

Where have you been?

And is it reading the good news that cheese won't kill you? In fact it's probably ok for you if you aren't lactose intolerant? I mean, good! Cheese gets a bad rap, it seems very unfair. And I am a deep lover of cheese.

Maybe it's reading about how invasive rats are altering the behavior of fish? Yes. One is on land, the other in the sea, but the rats are affecting whether a damselfish defends its territory. Why? The rats decimate populations of seabirds on islands, which means less seabird poop. Less seabird poop means less nutritious algae in the nearby reefs. The damselfish love to defend their algal salad bars, but if there's fewer birds, the salad bars begin to look a lot less Whole Foods and a lot more Shoney's (see if anyone else gets that reference from my childhood). A woman needs a man like a fish needs a...rat?

Also, I was thinking: Would any of you like to share your pest stories in the newsletter? I'm glad to read them over, have a reaction, drop some hot rat/bunny/raccoon facts. Thoughts?

Where have I been?

Science Friday is where! I was so excited and I was not fangirling at ALL. Really. Honest.

Also, my book got picked up by the Next Big Idea Book Club, so if you want to hear the five big ideas from my book...well now you can!