An open letter to Stephen Colbert from a clam expert

Abraclam Lincoln (photo source) next to a handful of Mercenaria mercenaria, a closely related kind of quahog (photo from Wikipedia), illustrating that Abraclam is indeed a chonker. To the right we have Arctica islandica, the famous long-lived clam, illustrating how hard it is to tell these clams apart without specialized training (photo from

Recently, a bit of an amusing clamfuffel arose when the Gulf Specimen Marine Lab, a research institute in Florida, began posting about a supposedly 214-year-old clam they named “Abraclam Lincoln”, in honor of potentially sharing a birth year with Honest Abe. The story went viral, and while some of their clammy claims turned out to hinge on flawed assumptions about how clams can be aged, it was still a worthwhile opportunity to communicate about the wonderful world of bivalves with people.

I was particularly impressed with how GSML went out of their way to correct the record as more info came in. Long story short, Abraclam is not the long-lived ocean quahog Arctica islandica (more on them below), but in fact a specimen of the southern quahog Mercenaria campechiensis, which lives along the Gulf coast and grows much more quickly than A. islandica. So the large clam they found was likely more like 40 years old, which is not too unusual for this species, rather than two centuries old. It also makes much more sense to find Mercenaria in Florida than Arctica. Additionally, external shell growth lines in Mercenaria are known to not be reliable for aging the species. The shell would have to be cut open to view internal lines to figure out how old Abraclam really is, which would require killing them. Fortunately, they released the clam rather than cut them in half for science.

Known range of Arctica islandica as a heatmap, compared to location of GSML on the Florida Panhandle. Source: OBIS
Slice through a Mercenaria campechiensis shell. The shell is lit from behind to show the annual growth lines. From Moss et al. 2021, written by fellow clam man David Moss, a friend of mine!

For what it’s worth, I still think Abraclam is an interesting specimen of M. campechiensis– they have a huge scar in their shell that would be interesting to learn more about (maybe they were hit by a dredge in their youth, healed the break and recovered to reach a ripe old age), and an unusual undulating margin at the edge of the shell that could be a deformity reported in the past literature for this species. Sometimes, scientists are wrong the first time, but we’re open about how we’re wrong, and everyone ends up learning more than we would have known otherwise.

So far so good. Then a bull had to wander into this delicate china shell with the entry of Stephen Colbert into the debate. I’ll let Stephen speak for himself, but needless to say, after his rant I feel a need to respond:

Before I dig into this clambake, Stephen, kudos to you for covering the whole story and not just the initial incorrect information. You addressed all the big inaccuracies, from the size not being tremendously out of the ordinary, to the incorrect species ID, to the incorrect age. Maybe it’s not so bad that people are getting their news from comedians rather than the news media these days! But while there were definitely some pearls of wisdom within your monologue, I have to point out some misconceptions here.

“The only thing more heartbreaking than the lies we were fed in this story…is growing up to be a clam expert!”

– Stephen Colbert

This is just plain false, since I’m not heartbroken, because clams are frickin’ awesome. Clams are way cooler than you or me, and that means by extension that the people who study them are pretty cool and interesting too (not really referring to myself. I’m just an eclamgelist along for the ride). So here are three facts about big old clams, and information about the clam experts who discovered these facts!

The ocean quahog lives to >500 years old!

Arctica islandica shell I saw on the beach in Massachusetts. This individual was likely several decades old when it died based on its fairly large size!

The ocean quahog Arctica islandica (which Abraclam was initially misidentified as) is tremendously long-lived, one of the longest-lived animals on earth! It has been confirmed to live to at least half a millenium! One individual caught off the coast of Iceland was aged to ~507 years by counting tiny growth lines in its shell via microscope, combined with radiocarbon dating. This clam was named Hafrún (meaning “ocean mystery” in Icelandic), but is sometimes called Ming due to it being born in the Ming dynasty of China. So put that in your Ming vase and smoke it Colbert!
Part of the shell of Hafrún, which was cut open to determine its age via internal growth lines. Source: Museum Wales

Several scientists worked on aging Ming, but Alan Wanamaker at Iowa State was a lead author on the original work. He uses growth lines in the shells of many clam species as records of climate change and is generally one of the nicest people you could have the opportunity to meet.

Tridacna gigas grows to over 4 feet long and hundreds of pounds!

Large specimens of giant clams that are around 3 feet long at the California Academy of Science collection.
The author sitting in a scale model of Tridacna gigas at the Monterey Bay Aquarium

Abraclam might be only 6 inches long (which is respectable as he/she is quite girthy; length isn’t everything, Stephen!), but there are other types of clams that are bigger than one Colbert in mass. The giant clam Tridacna gigas grows to over 4 feet long and weighs hundreds of pounds. They live on tropical coral reefs and use the power of the photosynthetic algae in their flesh to speed up their growth. So basically these clams are bigger and way more interesting than you, Stephen, since they get to go out and tan in the sun for lunch while you have to gobble down a slice of pizza.

Mei-Lin Neo at University of Singapore is considered the world’s leading expert on Tridacna, and has done more than almost anyone I know to describe all twelve currently known species of giant clams found around the world. She’s a tremendous advocate for giant clam conservation and gave an outstanding TED talk about them to boot. You should have her on your show to be honest.

Geoducks: they looked like that first!

WDFW employee holds large geoduck
A 6.5 pound geoduck and admiring Washington Department of Fish and Wildlife Volunteer (Source)

Speaking of girthy, long clams, I’d be remiss not to mention the geoduck, Panopea generosa. Pronounced “gooey-duck,” these clams looked like this long before any part of human anatomy existed, having been around in various forms since at least the Jurassic. They have a long siphon that they use like a snorkel when they dig deep in the mud, and they can live for almost 200 years.

Brian Black at the University of Arizona is an expert in using their shells as a record of climate change. He was part of a group that was able to stitch together the growth line records from multiple geoduck shells to make a continuous record of climate change going back to 1725. Seems appropriate to note that 1725 was the year that Casanova was born…a man who may have channeled some qualities of geoducks.

Local experts on Abraclam

I’d like to mention two of the experts who corrected the record about Abraclam Lincoln and provoked Stephen’s attack in the first place. Dr. Dan Marelli wrote an op-ed correcting the record on how Mercenaria clams are aged for the Tallahassee Democrat. He’s an expert scientific diver and has published papers on clams ranging from endangered scallops to invasive mussels. Scientific diving is crucial to understand clams in their native environment, and to assist in their conservation. If I had to choose who had more interesting stories at the bar, it’d be an easy decision to listen to the swashbuckling diver over the late-night TV host!

Dr. Edward Petuch at Florida Atlantic University reached out to GSML to make sure they knew the correct species ID for Abraclam. He is well-known for his work describing the change in ecology of mollusks in Florida and the Caribbean over the last several million years. GSML expressed interest in working with Dr. Petuch in the future, and I can confirm that I’ve had fruitful scientific collaborations start when other scientists have reached out to me about how I was totally, embarrassingly wrong. Being wrong in science is part of the job, and that’s why I’m glad this Abraclam story came out in the first place.

“So what does your son do? He’s a marine biologist. Does he work with dolphins? …I’m gonna say yes.”

-Stephen Colbert

To close out, I’d like to address Stephen’s assertion that my mom isn’t proud of me for being a clam expert. Stephen, I’ll have you know that my mom is the most enthusiastic patron of my clam science. She reached out to the local paper to anonymously tip them to interview me about my clam work, had me give a speech about clams at the local women’s group she’s a part of, and when I defended my PhD thesis, she made t-shirts to commemorate the occasion. I can confidently say I wouldn’t be Dan the Clam Man if it weren’t for her support. Thanks Mom!

Why I like scicomm on Mastodon!

A geoduck clam (also called "elephant clams") next to the elephant-like Mastodon mascot. The clam has along trunk-like siphon.
A geoduck clam (also called “elephant clams”) next to the elephant-like Mastodon mascot

Over the last couple weeks, I’ve seen hundreds of academics, nerds and everyday people I know open new accounts on Mastodon, in a phenomenon that has been called the great #TwitterMigration. Mastodon is an open-source microblogging platform similar in format to Twitter, but running on thousands of servers interconnected with each other in an open network called the “Fediverse” (referring to the fact that these services are “federated” to each other). Many researchers are disillusioned with the current state of Twitter, which was purchased recently by an erratic, bigoted oligarch, and are registering their disapproval by seeking out other places to share their science.

Personally, I am not “migrating” per se, as I have been using Mastodon for over 4 years now. I don’t intend to close my Twitter account, because I think the site will survive the current damage being done to it, though I’ve stopped posting for the time being, while they work through the process of learning the hard way that hate speech can never be allowed on the platform. I wanted to write about my experience using Mastodon to communicate science and why I think it has a lot of advantages over Twitter for certain use cases, precisely through the ways it does not seek to be a direct Twitter replacement.

Posting how I want

First of all, Mastodon gives me way more freedom to post the way I want. It is a true “micro-blog” in the way Twitter can’t be, since I get enough characters (500 at, and more on some servers!) to allow me to post a real paragraph. I have never found Twitter’s 180 characters to be enough space to really tell a satisfying story. Some people get around this by posting threads, but I also have never enjoyed writing threads! Other than that time I went on a giant clam fact rant. Mastodon also supports threads if you’re into that, and also allows you to set the visibility on your subsequent posts, so that your replies to yourself don’t spam everyone’s feed.

In my four years writing #clamfacts on Mastodon, I’ve written short facts. Long facts. Silly facts. Meaningful facts. I just have a lot more freedom with the format. Mastodon was also much faster to enable accessibility features like image descriptions than Twitter was. So the facts I shared are more accessible to disabled folks. While Twitter now includes alt-text, it still feels like Mastodon’s alt-text is a more mature feature. As with subtitles and other accessibility solutions, these features end up improving usability for everyone. In the case of alt-text, it gives me tons of space to describe scientific diagrams for anyone who might need additional context.

Mastodon recently added the ability to edit posts, which has been very advantageous for me, as a typo-prone individual. For Twitter, that feature is still locked behind a subscription. But even before editing was available on Mastodon, there was an option to “Delete and redraft”, which I used frequently to re-post when I had forgotten an image description, or to fix a typo. Mastodon has long provided far more options to control who can see a post and how, which is why I felt more incentive to be creative there than on Twitter.

A small pond by design: Engagement and sustained connection over reach

Twitter sometimes feels like an RSS feed with comments. Particularly for the more popular accounts or viral posts, while you can reply, there is such a torrent of feedback on the other end that it is difficult for them to respond to everyone. For my niche specialized clamposting, I am not interested in going viral. I just want to engage with people and learn from them as much as I share knowledge with them.

Mastodon is very well designed for this. Your posts get shared across the federated network, but only as much as other people “boost” it (analogous to retweeting) or reply to it. There are favorites (similar to the like button), but those are mostly just a direct message that someone liked a post, and have no impact on whether it spreads larger over the network. So the main people seeing my posts are my direct followers. And because Mastodon is a reverse chronological feed, with no opaque algorithm determining whether or not to show someone something, I am more confident that a bot moderator isn’t going to misidentify my clam content as NSFW and hide it by default from people’s feeds.

Culturally, Mastodon is driven by following people, and making your feed for yourself, rather than having posts from people you don’t follow pushed to you by a computer. If you follow someone back, you’re more likely to make a lasting connection through time, rather than trusting some algorithm to figure out who you enjoy to see. This leads to more lasting, meaningful connections in my experience. Truly powerful scicomm never happens in one direction; it relies on exchange.

I think that Mastodon will stay like this in the future, even as it continues to grow by leaps and bounds. Rather than one giant, sometimes dangerous ocean like Twitter, it’s more of a collection of small ponds. My reach is restricted to my followers and their followers, and sometimes their followers’ followers. That produces much more meaningful, sustained connections.

Hosted and moderated by scientists, for scientists

My home since the start has been, a server run by a scientist in the UK going by the username Quokka. Recently he recruited another scientist and me to be moderators on the server, and we’re looking to add more. But since the start even before I was moderating myself, I’ve felt more secure sharing science when it’s hosted and moderated by another scientist. Even before Twitter laid off moderation staff en masse, and before the site announced scientific misinformation is now fair game, Twitter was not a place run by scientists, for scientists. If someone replied to me with misinformation about the coronavirus or climate change, my recourse against them was limited, since the moderation staff there are not exactly experienced peer reviewers. On Mastodon, there have always been data-conscious nerds running things. And now, there are a constellation of sciencespecific servers to choose from!

Science, including scicomm, is always more at home in an open-source environment

The last point I’ll bring up is that science always works better in an open-source environment. Mastodon is available free and open-source on Github for anyone to download, alter and run themselves. I prefer to use such open-source solutions in my own scientific work, from including Rstudio, QGIS, ImageJ, Raspberry Pi, Arduino, Ubuntu, Inkscape, Firefox/Thunderbird and more. So hosting my science communication on an open platform feels like preaching what I practice, as opposed to allowing a for-profit company to own my scientific content.

For all the reasons above, I have been extremely pleased to see the wave of scientists, technologists and other interested people join Mastodon over the last few weeks. I feel Twitter will still have a place in my science communication once it has worked through its current drama. But in the meantime, I look forward to sharing my clam facts with all the people I can, in my little pond on Mastodon.

Recent Science Communication!

At Biosphere 2, our science is essentially done in public. Every time I’m in the water checking on our clams and the sensors around them, I’m in view of the public and essentially an attraction for the public to watch. This is a really unique way to do science unlike any of my past experience, when I’ve been out in the field with a collaborator, or in the lab with a laboratory technician. I was initially intimidated by the idea of doing my science with an audience, but I’ve decided to lean into it as a huge opportunity. It is rare that the public gets to see all the steps going into our science; they usually only see the end of the story and not the whole journey leading up to that point. So recently I participated in two new ways of sharing my work while it’s in progress with the public.

The first was a collaboration with Mari Clevin, a videographer with the University of Arizona who made a really nice profile of my crazy clam journey. It was a lot of fun showing her around B2, trying to capture what it’s like to work here. It was fascinating seeing how all her footage and interviews came together into a video, and how she captured the key points of our conversation into a narrative!

The other scicomm event I participated in was a “Research Show and Tell” event run by the PAGES Early Career Network. Early Career Researchers include PhD students, postdoctoral researchers like me, and early career faculty. The ECN is intended to help us band together to share opportunities and plan events relevant to our interests. Among the North American regional representatives for the ECN, we saw a real need for more informal ways to share our research to an advanced audience of our peers. We’re all burned out from Zoom webinars, and on the other side Zoom coffee hours don’t typically provide much opportunity to share scientific content, so there’s a real need for events in the middle. So I was excited to share my research with a group of my peers, touring them around the Biosphere, showing them my clams via pre-recorded video and then having a Q and A to describe the work. It was a lot of fun and you can watch the whole hour-long event below!