We’d been wanting to do a family holiday in Ireland for years and so we finally did. I’d been to Dublin twice before for work visits and we wanted a more rural experience. On others’ recommendations, we started in the city of Cork. With some sleuthing and asking around, I realized that we weren’t far then from gorgeous Killarney National Park, and then it wasn’t far west from there to get to Valentia Island, where incidentally there is something amazing for palaeontology-lovers. There was no deterring me at that point from visiting what I’d only read about. I’ll mainly let the images tell the story.
Stomach-Churning Rating: 0/10; fossils and scenery. Kick back and enjoy.
Island map- it really is that simple to get around! The harbour town of Portmagee is damned adorable.
Driving in (no I am the passenger; not taking photo while at the wheel!)- excitement level = 8 and building… “Tetrapod carpark” sign ratcheted up the excitement and was amusing.
Headed to the trail; excitement level = 9…
Looking down onto the site (on the right); excitement level = 9.5; beauty level = 9.5 too!
Now, the site of what is broadly accepted by experts as a ~Middle Devonian tetrapod(omorph)’s fossil trackway(s) was originally described by Stössel in 1995. To me, that feels like a recent discovery but it is 22 years ago. The only other well-preserved, widely-accepted, probably-terrestrial, Late Devonian tetrapod(omorph) trackways are from the Genoa River site in Australia; described by Warren et al. in 1972. Those trackways even reveal some details of the fingers and toes; these do not. Other tracks are either isolated footprints of minimal scientific value/clarity, subaerial (i.e. underwater), not clearly stem-tetrapod (or now argued to be arthropod or other origin), not Devonian, or controversial for reasons I won’t get into here. The famous Zachelmie tracks in Poland are strong contenders but remain controversial to more than a few researchers in terms of who made them and in what environmental/substrate context; but their Middle Devonian age seems robustly agreed. Clack and Lucas have reviewed the relevant evidence recently. So there are essentially at least two, and arguably three, places in the world that you can visit to view tracks like these and it was a joy to go visit one set. (Easter Ross, Scotland may be a fourth site but it is reasonably disputed in age and maker)
There is a “however,” however- Falkingham and Horner showed how lungfish can produce tracks (with fins and heads together) that look like these, to some viewers (but not to others) and in some substrates (mud; not sand as at the Valentia site)– so there is still uncertainty for some tracks although the lungfish-feeding claims have also been vehemently disputed too. Without finger and toe impressions, claims of discrete tetrapod tracks are risky, and it would be wrong to say that the Valentia Island footprints are uncontroversially or 100% certainly tetrapod in origin, although they are (late-Middle) Devonian and made by some sort of animal, and very likely a tetrapodomorph at least.
Stössel et al. also published a recent update on these Valentia Island tracks with more information. I wish I’d come across that before I visited (oops!). That study reports on a total of nine(!) trackways from the area, adding to the 1995’s first one (the “Dohilla locality, Do 1”– see diagrams below), and describes them as Middle Devonian (with a radiometric dating of 385 million years old). I’m not enough of a geologist to evaluate that; prior reports had focused on Late Devonian or so.
Rippled sandstone example; preservation characteristic of the trackway area/Valentia Slate Formation. It’s an alluvial deposit (freshwater floodplain), interpreted to lie inland from the coastal marine deposits. Raindrop impressions above the plane of the tracks raise the possibilities that the tracks were made on (moist) land.
The island has plenty of signs advertising the tracks as a tourist destination but happily(?) there are no knick-knack shops stocked with plush tetrapods, or other developments at or near the site. One simply winds down a very narrow road near a radio station and old lighthouse, and parks then walks to see the tracks. No fancy crap; just AWESOME sights to take in, and some good educational information.
Explanatory plaque at the viewing area. Pretty good!
Nice image of where Valentia Island was; although the 385 My age may be exaggerated. It’s not clear how old the tracks are but “Mid-to-Late Devonian” might suffice depending on how you view the evidence. The tracks were the “oldest known” at the time of discovery and remain close to that, but challenged by the Zachelmie trackways (see references above).
Explanatory signs on the peak above the shore. Given the likely tetrapod(omorph) trackmakers like Acanthostega-style critters, the adult animal may have been able to breathe air with lungs and underwater with gills.
Enough exposition– let’s expose those tracks! (images can be clicked to enlarge)
My first close-up look at the tracks. Whoa! Small tracks are presumably hand (manus) impressions; larger ones are foot (pes). The tracks go in an alternating fashion (like a salamander’s walk) and the animal was probably going from the bottom-right toward the top-left. Moss and moisture obscured some of the prints that day, sadly. The tracks are oval, with the long axes perpendicular to the direction of travel. There are some pesky geological deformations of the trackway, faults, and other distortions. 145 footprints in total are reported from this one trackway!
Trackway as it turns to the left and gets harder to follow. John-shadow for ~scale. Frustratingly for me, a little rivulet was coming down the hill across the left side of the trackway and hiding much of the detail of the end.
Alternative view of the majority of the tracks; turned ~90 degrees from above two views.
Zoomed-in view of the tracks from head-on (opposite the view in other photos); i.e. western position looking east (ish). I added red and blue dots to roughly outline the right side of the main trackway (red) and the second one (blue), which crosses it and may have been made after it.
Even these nice trackways, viewed by an expert, take some unpacking. Here is some:
Diagram of known tracks at the site by Stössel et al. 2016.
Diagram at view site with extra tail (or body) drag trail crossing the main tracks; described later by Stössel et al. 2016.
I’m not at all a religious person and I don’t really like the term “spiritual” either, but this experience was emotional for me. Awe is certainly the best word to describe what I felt on viewing these tracks. The literature just doesn’t do them justice; nothing beats a first-person experience like this. We were lucky with excellent weather, too, and we were almost alone during the visit so there was pleasant silence in which to contemplate the tracks. I brought my copies of three papers on the trackways and, struggling with the wind, compared them with the visible tracks to understand what other scientists had seen. That amplified the experience enormously for me.
Even if they turn out to be non-tetrapod or younger or something less exciting (“sham-rock”?), it was thrilling to see the Valentia Island tracks and think about what happened ~385 million years ago when they were made by our very distant cousins, along the land-water interface of space and time.
(I also feel bad for online reviewers that were disappointed with the site- it’s hard to grasp the scientific importance and/or accept the evidence, even with the decent information available on-site. Even if people know the nice fossil record of dinosaurs, they may not know how good the fossil record of early tetrapods is and how confidently we can figure out what happened in the Devonian emergence of tetrapod(omorph)s onto land. But some visitors clearly got it.)
And, looking at the site myself, I realized how many more tracks might be buried under the cliffs of the site- the first trackway emerges from under a cliff and thus must still be preserved for some distance underground, awaiting future exposure. What more might we learn about that single animal and others that made tracks around the same time? I hope to live to find out. I feel a personal connection now to these tracks, left pondering what story they preserve– and hide. I’m glad I’m able to share my own story with you, and encourage you to make the visit yourself!
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