Last time, I noted that photographs of the exact same object, even under the same lighting conditions, can come out different colours. That is one of the two reasons why I am not persuaded that the very different colours of my photos of the two Supersaurus scapulae is strong evidence that they are from different individuals.

The other reason is that, as BJ Nicholls pointed out in a comment on that post, “Color in fossils can be misleading even in real life. As bones erode out, surface float pieces can be bleached on exposed surfaces. Bones within a bed can vary a lot in color too.”

Here’s an example:

What we have here are some of bones from the skeleton of Charlie the monitor lizard. After I extracted these bones from Charlie’s decomposing carcass ten years ago (can it really have been that long?!) I have left them sitting on a tray, awaiting articulation.

At the top of this photo is a scapulocoracoid; at the bottom, some dorsal vertebrae. As you can see, the former has bleached white, while the latter have remained ivory coloured. Remember, these are bones from the same individual that were extracted at the same time (give or take maybe a day or two), and that have been in exactly the same situation (on a tray, on a window sill, in my office) ever since.

The moral: bone colour doesn’t really tell you much at all.

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In part 5 of the Supersaurus series, I made the point that my photos of Scap A and Scap B seem to show them as being very different colours, suggesting different preservation. However …

I don’t trust that line of evidence as much as I might for two reasons. First, different photography conditions can give strikingly different coloured casts to photos, making similar bones appear different. And second, I know from experience that bones from a single specimen can vary in colour and preservation much more than you’d expect.

The first of these points has just been brought home to me by an unrelated experience. The rendering on an outside wall of our house had come loose, and needed to be removed and replaced. I am soliciting a quote for doing the re-rendering, and took some photos to send to the builder who might be doing the work. First, the whole of the relevant wall:

And now a close-up of the leftmost part, around shoulder level:

Now these photos were taken with the same pretty good camera (Google Pixel 4a), in the same place, under the same lighting conditions, eleven seconds apart. Yet in the first photo, the underlying brickwork is brown, and in the second it’s grey — presumably because the camera made a judgement about white balance based on what was in its viewfinder at the moment each photo was taken.

Here is the same part of the wall, juxtaposed, from both photos:

Let this be a cautionary tale: don’t over-interpret colour from photos. When comparing the colour of two fossils, the best thing to do is put them physically next to each other so you can see both at once under identical conditions. (Sadly, that wasn’t an option with the two Supersaurus scapulocoracoids.)

Years ago, the roof of our summer-house suffered some water damage and had to be replaced. So I converted it into a woodshed which I attached to the side of our house. As well the store for our firewood logs, it’s also where I keep many of my decomposing corpses — most of them in boxes and bags, a few of them not. Recently, a self-seeded clematis Eccremocarpus scaber has worked its way through a crack and started growing over the specimens and the logs:

Most of the specimens are hidden from view, apart from a tortoise that you can make out in a translucent box over on the right. The centrepiece here is some kind of medium-sized mammal, consisting of the skull and much of the vertebral column and ribs, which my youngest son brought back from a camping trip for me. Elsewhere in various boxes and bags are multiple kestrels, a falcon, several other birds, a couple of bearded dragons, a snake, a mole, a rat, and miscellaneous small mammals. Some day, I will prep out all their skeletons. I really will.

Last week I went to Halifax, Nova Scotia, for the twice-yearly meet-up with my Index Data colleagues. On the last day, four of us took a day-trip out to Peggy’s Cove to eat lunch at Ryer Lobsters.

We stopped off at the Peggy’s Cove lighthouse on the way, and spotted a vertebrate, which I am pleased to present:

mike-with-whale

It’s a whale skull, but I have no idea what kind. Can anyone help out?

So much for vertebrates — it was really all about the inverts. Here are six of them:

mike-with-lobster

I have a 2lb lobster here; my colleague Jakub went for two 1lb lobsters, as did Jason and Wolfram (not pictured). That’s Wolfram’s lobster closest to the camera, giving a better impression of just what awesome beasts these were.

Peggy’s Cove: recommended. For vertebrates and inverts.

(Thanks to Wolfram Schneider for these photos.)

 

Marble Mountains trilobites

 

These animals experienced days less than 23 hours long, and years with close to 400 days.

Emeus crassus mount

In a back room at the Field Museum, from my visit in 2012.

I took a lot of photos of the neck, which nicely records the transition in neural spine shape from simple to bifurcated–a topic of interest to sauropodophiles.

Emeus crassus neural spines

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Now considered a junior synonym of Supersaurus, on very solid grounds.

Incidentally, unlike the neural spines of most non-titanosaurian sauropods, the neural spine of this vertebra is not simply a set of intersecting plates of bone. It is hollow and has a central chamber, presumably pneumatic. Evidence:

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