Tutorial 46: how to write an abstract

We live in stupid times. As I write this, Google Scholar’s front page is advertising “New! AI outlines in Scholar PDF Reader: skim per-section bullets, deep read what you need”. Yes: it’s using AI to provide a short summary of what’s in a paper. Wouldn’t it be great if instead of a profoundly fallible AI summary, we could read a summary written by the actual authors, who know the material inside out?

We can, of course. It’s called an abstract, and pretty much every paper has one. Back in ye[1] olden times, authors didn’t write them: they were created by third parties to summarise the main points of the article. These days, you — the author of a scholarly article — are expected to provide the abstract, typically 200-300 words or so, that in some sense represents the article.

But in what sense?

Too many abstracts represent their article by trying to whip up enthusiasm for it — not summarizing the findings but teasing the reader as though to pull them in like a clickbait headline. That’s really not how it should be, because the reality is that an order of magnitude more people — maybe two orders of magnitude more — will read your abstract than will read the paper it’s attached to. You can’t make people read your paper (especially if it’s behind a paywall), so you need to make the abstract count.

Here, then, are four simple rules for writing an abstract that gets the job done.

1. Summarize, do not introduce. I’ve written here before about how an abstract should be a surrogate for a paper, not an advertisement for it, and this remains the single most important thing to remember. For those 99 in 100 people who will read the abstract but not the paper, we need to make sure that the abstract tells them what they need to know. So don’t write:

The body size of the snake was estimated based on extant snakes with a morphometric affinity to Palaeophiidae. The cosmopolitan distribution of Pterosphenus schucherti is modelled based on the sea surface temperature (SST) constraints of the modern cosmopolitan snake Hydrophis platurus, and the known fossil localities of the species. The present findings provide crucial insights into the global paleoecological landscape of the Eocene

Instead tell us what what the body size[2] of the snake was, what cosmopolitan distribution you found, and what insights these findings provide in the global paleoecological landscape of the Eocene.

Otherwise people are going to read your abstract, and go away with the message “this snake had a body of some specific size, and had a distribution, and that provides some insights”. Is that what you want? Huh? Huh? No. Didn’t think so.

2. Do not assume specialist knowledge. This is difficult because we work in a specialist field and some amount of specialist terminology is inevitable. But we should still do our best to reduce the amount of background knowledge a reader needs to make sense of our abstracts — again, because the potential readership is so much wider than for our actual papers.

Needless to say (I hope), we should strive to make all our writing as comprehensible as possible — always writing “it flies fast” rather than “the taxon under consideration exhibits velocitous aerial locomotion”. But that goes double for abstracts. So for example, one might write:

The thickness of the articular cartilage between the centra of adjacent vertebrae affects posture. It extends (raises) the neck by an amount roughly proportional to the thickness of the cartilage.

For those versed in the neck-posture wars, it’s hardly necessary to point out that extension of the neck involves raising it (and flexion involves lowering it), but for the wider audience that reads an abstract it’s worth spelling out.

3. Omit needless words. This is, famously, one of Strunk and White‘s rules, and it remains excellent advice. As with “Do not assume specialist knowledge”, this is good advice for all writing but especially so for the abstract.

When I started my palaeo Masters (as it then was) at Portsmouth, I had a very bad habit of writing unnecessary double negatives of the kind the Sir Humphrey Appleby might use. Instead of saying “Taxon X resembles taxon Y”, I would say “is not dissimilar to”. I did this all the time. One of the best things Dave Martill (my supervisor) did for me was to red-pen all these circumlocutions. I hope I’m better now. You be better, too

(When I was doing the video to publicise Brontomerus in 2011, I mentioned Utahraptor near the end, and stupidly described  it as “not unlike Velociraptor“. I was so mortified when I heard the first draft of the video that I got in touch with the videographer and begged him to snip out the “not un-“. He did a great job, and I bet you can’t hear the join.)

4. Write the abstract after the paper, not before. It’s so tempting, isn’t it? You have a new, blank document. You type in the title, your name and academic address, and the word “Abstract”. Then you go ahead and summarize what the paper is going to to say.

Except you don’t know what the paper is going to say. Sure, you have a sense in your head of how it’s going to run, but no project plan survives contact with data. In my experience, almost every paper ends up saying something I didn’t anticipate when I started, or leaving out something I did expect to say, or drawing a different conclusion from the one I expected. (When I started to write my 2009 paper on Giraffatitan brancai‘s generic separation from Brachiosaurus altithorax, it was with the intention of proving that “Brachiosaurus” brancai was a perfectly cromulent species of Brachiosaurus, and I ended up discovering the exact opposite.)

So now I leave the abstract till last, so there is no danger that the ghosts of its early version will haunt it. I have a paper in the works now that’s reached 25 single-spaced manuscript pages and 15 illustrations, which I hope to submit within a week — but it’s abstract currently reads as follows:

Abstract

XXX to follow.

Only when the paper is actually complete will I go back, read through it, and summarize as I go, trimming down to 250 words or so if necessary when I’m finished.

Go thou and do likewise.

Notes

1. “Ye” should be pronounced “the”, as it was in the days when it used to be written. It was always and only an abbreviation, “y” standing in for the “th” letter-pair. Similarly, the “e” on the end of “olde” was silent. So if arrange to meet your friends at a pub called “Ye Olde Hostelrie”, you should pronounce it “the old hostelry”.
2. “Body size” as opposed to what other kind of size? Soul size? When you write “size”, body is understood. Just write size. And while I’m at it, do not give your paper a title like “A new, large-bodied omnivorous bat” or, worse, “A new large-sized genus of Babinskaiidae”. Seriously — large-sized? Again, as opposed to what? Big-hearted?

Source: https://svpow.com/2024/11/13/tutorial-46-how-to-write-an-abstract/