In which fangirling turns into philosophy

Textbooks may portray science as a codification of facts, but it is really a disciplined way of asking about the unknown. — Andrew Knoll, Life on a Young Planet

Some books change your life. When I was 12 or 13 or thereabouts, SJ Gould and others’ Book of Life rekindled my interest in prehistoric life, introduced me to the Cambrian explosion, and opened my eyes to a whole new worldview. It’s one of the reasons I hold a degree in evolutionary biology.

Life on a Young Planet was not a life-changer, precisely. That’s not why I love it to pieces. By the time I read it, I’d gained an appreciation of just how complex and full of uncertainty natural science was, and the book was permeated by an awareness of this complexity. Also, it was simply beautiful writing.

(I can’t emphasise the importance of good writing enough. I’ve read too many papers and books [Crucible of Creation and The Plausibility of Life, I’m looking at you] that had good information but were so atrociously written that I nearly put them down despite being fascinated by their subject.)

Last month, the author of Life on a Young Planet, Harvard professor Andy Knoll, came to visit my university. I was practically bouncing with excitement from the moment I saw his name on a newsletter. He gave four lectures in total; until the very last one, I actually contemplated getting my copy of the book signed. Or, to be a fangirl and a nerd, my printout of his lovely biomineralisation review. (I still can’t decide if I made a mistake. Damn, I didn’t even ask a stupid question. Four lectures, and I just sat there and drooled over my notebook.)

Knoll is nearly as good a speaker as he is a writer. He doesn’t have the liveliest voice and speaks quite slowly, but if you can get past that, his lectures are really good. (I’m glad of that; I really don’t like losing my illusions!) They are solid structures that you have no difficulty following the logic of.

Let me put it this way – Andy Knoll is an excellent storyteller.

That got me worrying, because I’m a sceptic and (truth be told) a little bit of a cynic at heart, and because over the years I’ve done a lot of navel-gazing about belief and knowledge and conviction. I have a tendency to grow suspicious when I feel too certain about something.

Am I – are we – too often blinded by good storytelling? How often do we get so enamoured of good ideas that we try to force them on situations they don’t fit? And how often do we doubt something just because it sounds too neat?

Here’s the specific example from the Knoll lectures that made me think of this. Knoll is a champion of the oxygen + predation explanation of the Cambrian explosion. (I didn’t realise he was involved in that paper until it came up in the lectures…) He is also an advocate of a similar explanation for the diversification of single-celled eukaryotes 250 million years before the Cambrian. He convinced me well enough, but then I immediately thought – really? Is it really that simple? Does one size really fit both events?

I often take note of these “pet ideas” as I read scientific literature. A group of phylogeneticists uses microRNAs to tackle every tough problem ever. A palaeontologist interprets every squishy-looking Cambrian weirdo as a mollusc. Researchers in the biomineral field look for slushy amorphous precursors to crystalline hard parts everywhere. (Remember, all generalisations are false ;))

Just to be clear: I’m not at all saying that being a “pet idea” automatically makes something wrong or suspicious. For instance, the hunters of amorphous biominerals have some good theoretical reasons to look, and they often do find what they’re looking for. Likewise, I’m impressed enough with Andy Knoll’s pet hypothesis about the Cambrian that I’ve rethought my own pet ideas about the subject.

I’m also not accusing these people of being closed-minded. Going back to Knoll, IMO he demonstrated ample healthy scepticism about his pets during his post-lecture Q&A sessions. (Which makes me a bit less nervous about the neatness of his stories.)

Someone better versed in the philosophy and sociology of science could probably write a long treatise involving paradigms and confirmation bias and contrariness here. I’m even less of a philosopher than I am a geologist, so I think I’ll leave the deeper insights to those who have them.

Meanwhile, I’ll continue to be a fan of Andy Knoll and appreciate a good scientific story. So long as I remember to look beneath the surface – both of good stories and of my own suspicion of them…

 

Endearing optimism

Scientific American online made me smile today. I get the newsletter; I don’t usually read it, because the SciAm website ranks somewhere between Cracked and TVTropes on the scale of time sinks. I hardly need another chance to procrastinate. Anyway, for some reason I did open several articles this morning. One of them was headlined “Earth’s Days Are Numbered,” and of course I clicked the link for the opportunity to grump, because I was pretty darn sure that the title was pure sensationalism and I’m mean like that.

I was right. Right after the headline, the article (which they borrowed from Nature) warns us of the impending catastrophe thus: “Researchers calculate that the planet will leave the sun’s “habitable” zone in about 1.75 billion years.”

Yeah. Should I laugh or should I cry? (I have to say I laughed. I must be in an uncharacteristically charitable mood today.)

But then I read the whole thing, because my officemate started wondering what would kill poor earth in 1.75 billion years, and that made me wonder. Was it orbital instability, or was it just grumpy old Sol getting hotter and roasting us? (To spare you the suspense: it was the sun.)

The article closes with a quote from one of the folks who did the maths. A really sweet, naive, optimistic quote. A quote that makes you think this guy would never ever write dystopian sci-fi. Here’s the last paragraph and the quote:

Just as the sun brightens and the Earth becomes too hot for life, Mars will be entering the habitable zone. “If humans are going to be around in a billion years, I would certainly imagine that they would be living on Mars,” Claire says.

I… just… awwww!

Maybe I’m a cynic. (No, scratch that “maybe”.) But I’m also an evolutionary biologist and have more than a passing familiarity with the history of life. If you show me a species of animal that survived even for a hundred million years, never mind a mammal that lasted a billion, I’ll be impressed*.

(Of course, there could be a chance that the human lineage draws the jackpot and survives. Technically, cladistically speaking, maybe, all of our descendants should be called humans. “Human” is a colloquial term, not a clade name, but let’s forget that for a moment. Even so, I’ll bet you my beloved hat that whatever’s left of us in a billion years would only be “human” in technicality.)

Even though I should probably rage at the way these guys make it sound like humans being around in a billion years is a plausible idea, it only kindles a strange fuzzy kind of warmth around my shrivelled little heart. There go my principles… 😉

***

*No, “living fossils” don’t last billions of years. Don’t get me started on living fossils.

Superfood shelf. Just-fucking-what.

After feeding every stupid health scare ever with its “free from” labels, Tesco has reached a new low. Or maybe it reached it long ago and my brain just refused to see it.

The damn place has a SUPERFOOD SHELF now. Because salad can’t just be healthy, it has to be SUPER healthy.

Image0059

Urgh.

I have to go and do some real science now.

In which I *don’t* blame journalists

Given the existence of this blog, you might have guessed that I’m interested in communicating science to a wider audience. Recently (well, in November) I went to one of Sense About Science‘s media workshops to learn more about science communication – specifically, about the representation of science in the media and issues surrounding same. When I’d digested the experience, I had some thoughts. Then I committed them to writing. Then the writing sat in a folder on my desk for half a year. I think it might just be time to publish it 😛

(Although this should go without saying, I don’t speak for all scientists. I have a personality and I have experiences, and both of those may distort my perspective. Read the following as my personal opinion.)

*

Once upon a time, I was a regular reader of ScienceDaily. It’s one of those places where science news gather, and I was interested in science news. I’d never been a big reader of other news, so it suited me perfectly.

Except I’m a pedantic nerd, and reading press releases can be… trying for my kind. I eventually got to the point of asking my supervisor how much scientists had to do with press releases of their papers, because so many of the ones I’d read on SD seemed to have been written by people who either wanted to blow everything out of proportion or simply had no clue.

The boss answered that the researchers would provide source material, but the press office write the actual release, and poor scientists can’t do a whole lot about its final incarnation. He made no secret of his dismissal of the press office, and opinionated little crusader that I am, I felt vindicated.

For a good long while, then, I felt completely justified in griping about journalists. They were, after all, churning out overblown claims and garbling perfectly good science to turn it into news. Was it a wonder, then, that so many people were becoming jaded and mistrustful of science? If you read articles touting miracle cures for cancer and marvelling at the biggest, oldest, most awesomest something ever, if every week decades-old paradigms seem to be turning on their heads, it isn’t at all surprising that you’d end up as some of my online discussion partners did. I saw these people, dismissive of science, firmly convinced that since science changes like the wind, it isn’t worth believing. Today’s knowledge will just become tomorrow’s outdated theory anyway. It infuriated me.

Sometimes, the scientists themselves seemed to be part of the problem. Remember “Ida,” the beautiful Eocene primate fossil? The sensational claims of her being a “missing link” in our own ancestry came from her describers, not their press offices. Likewise, the press release in which palaeontologist John Ruben was quoted as saying (to any vaguely well-informed dinosaur nerd) hugely outlandish things that weren’t even implied, never mind discussed or demonstrated, in the corresponding paper (Quick and Ruben, 2009), could hardly have been all the journalists’ fault.

I was (and still am) angry at such scientists. In my perception, we were at war with anti-science sentiments, and they were playing into the enemy’s hand. Still, it appeared, most of the problem was journalism. Well, this media workshop provided me with a few reality checks. It changed my perspective in some ways, and reinforced my convictions in others. Let me count the ways.

The opening panel in the workshop featured scientists. My first surprise was learning that one of them had absolutely no issue with journalists. He loved making headlines, even if said headlines would make my hair stand on end. He’d found that journalists were generally decent people who want to Get It Right as much as you do.

Then, of course, we got the journalists’ perspective. Their insane work schedules, their pressure to sell stories, their attempt to do so while still retaining accuracy. All in all, they did seem like decent people who wanted to get it right.

But here’s the first problem: given the demands of the job, that can be very difficult to achieve. If, as one of them explained, you might have to report on something even before you’ve had time to actually read the sources, you can very easily make mistakes with the best of intentions.

This is a problem we can help journalists with. Make sure the press office has clear and accurate information so the press release isn’t complete nonsense. When you write a paper, make sure your key points are made clearly and concisely right in the abstract, not in a long and complicated paragraph on page fifteen, where the people writing the news will never see it. If a journalist requests your help, be there to explain and clarify and provide non-wtf quotes. That’s one thing the panellists were very clear about: they need scientists’ cooperation, and they often need it at short notice.

The second problem, I think, is a more fundamental one: scientists and journalists mean something different by “getting it right”. (At least in my idealised world where all scientists think like me. :)) A journalist primarily wants to sell a story, where a scientist primarily wants to increase human knowledge. Of course, scientists also want to sell their stories – no one wants to publish papers that are never cited, and no one wants their career to wither without funding. The crucial difference is, I think, in what each group means by a good news story, and what compromises they are willing to make in order to write one.

For example. To me, direct fossil evidence of how an ancient fish reproduced (Long et al., 2009) is fascinating in itself. I was pretty miffed with the press release accompanying this publication, which turned a relatively mundane finding about the oldest evidence of live birth in vertebrates into a sensational story about the oldest evidence of sex in animals.

If it wasn’t a gigantic digression, I could rant long and hard about all the ways in which this press release mangles science to make it more newsworthy, but the real question is this: does it matter? (To people other than me, I mean.) Is this distortion of facts necessary or even beneficial for getting non-science junkies even a little bit interested? Must we, the scientists, lower our standards of rigour to engage the general public?

Here’s another one. In early 2009, New Scientist ran a controversial feature article about the limitations of the tree of life concept. This article included a discussion of marine ecologist Donald Williamson’s unorthodox hypothesis that the larvae of many animals – which often look very different from their adults and discard most of their baby bodies during metamorphosis – originated from ancient hybridisation events between distantly related critters.

To most people knowledgeable about evolution, genomics or developmental biology, his claims don’t stand up to scrutiny. In our eyes, Williamson is promoting a very implausible hypothesis on weak and superficial evidence. I would only ever bring up his ideas as an example of a “loony theory,” most likely wrong but perhaps interesting from a sociological point of view. But here is a high-profile science magazine, presenting it as an exciting, “different,” and above all, credible alternative to the mainstream view(s) of animal evolution. (In the section on Williamson’s hypothesis, there is no indication of how “fringe” this idea is considered in the scientific community.) The writers at New Scientist were interested in cool stories, and not necessarily in critically examining them.

I see these issues as a fundamental difference between the two professions. I think it’s very difficult to reconcile our demand for accuracy and sound evidence with the journalist’s job. Unlike some audience members at the workshop, I don’t think a formal education in science is necessary to be a good science journalist. Like anything else, a “feel” for science can be picked up by being exposed to lots of it, and scientists are (or should be) there to help out with unfamiliar issues.

However, I do think that we as scientists can’t expect journalists to tell the stories we want them to tell. We can’t expect them not to “dumb things down”, we can’t expect them to respect technical distinctions they don’t see the importance of, and we can’t expect them not to sensationalise a discovery whose true importance is subtle and requires a lot of background knowledge and perhaps a good deal of pre-existing science nerdery to appreciate.

And who knows, maybe the masses reached by sensational news stories are worth a few disillusionments. The angry are always the loudest, and they may not be the majority. I don’t know. But if you are dissatisfied with the way science is represented in the media, griping about journalists to your colleagues isn’t going to solve the problem. This is the age of communication. Anyone can talk to the public. So if you want to change what they hear, why would you wait for others to say the things you want said? Go forth, scientist, and make your voice heard!

***

References:

Quick DE & Ruben JA (2009) Cardio-pulmonary anatomy in theropod dinosaurs: Implications from extant archosaurs. Journal of Morphology 270:1232-1246

Long JA et al. (2009) Devonian arthrodire embryos and the origin of internal fertilization in vertebrates. Nature 457:1124-1127

If only!

Ah, abstracts. Because the world has no attention span, and there isn’t enough time in the universe to read every new paper relevant to your research anyway, we need abstracts in front of scientific articles. Heck, if you are anything like me – and I’m told this is a general scientist thing, not just my laziness – it’ll be an especially important paper indeed that you actually read in full. (Well, that or especially bloggable.)

So you write abstracts to sell your stuff, because abstracts are all most people will ever see of your work. And in your effort to sell your stuff, you sometimes end up writing total fucking nonsense. Probably without even noticing it. (I like to assume the best about people.)

Like, for example, where Mu et al. (2013) write in the abstract of their recent study about regenerating fingers in mice that…

The differences between amphibian regeneration and mammalian wound healing can be attributed to the greater ratio of MMPs to TIMPs in amphibian tissue.

To make the above sound less like a foreign language: MMPs [= matrix metalloproteinases] are protein-chomping enzymes that modify the extracellular matrix that surrounds and connects cells in a tissue. TIMPs [= tissue inhibitors of MMPs] are proteins that interfere with their function. And yes, MMPs are important for regeneration… but if the difference between the amazing leg-regrowing abilities of newts and mammals’ almost complete failure to regenerate even one puny finger were that simple, we would have eradicated one-armed bandits long ago.

If only it were that simple!

(Remind me to make fun of my own papers if/when I ever get something published. I kinda feel bad for nitpicking other people’s language as if I never wrote anything stupid… >.>)

***

Reference:

Mu X, Bellayr I, Pan H, Choi Y, Li Y (2013) Regeneration of soft tissues is promoted by MMP1 treatment after digit amputation in mice. PLoS ONE 8:e59105

Macroevolution Airlines

(This post has been mostly written for a long time but I never got round to publishing it. It’s kind of my darling baby, and I never felt quite ready to let it out into the world. Well, every parent has to let go at some point…)

In the creation vs. evolution section of Christian Forums, “macroevolution” is a common topic of name-calling discussion. At some point in what seems like every other thread, a creationist demands “proof” of macroevolution. The common reaction from the evolution side is that the creationist doesn’t understand evolution, and macroevolution is just lots of microevolution, and here is a list of observed speciation events anyway. While the first point is true more often than not, I have been increasingly uncomfortable with the second lately. To my mind, and I think to anyone interested in palaeontology and/or evo-devo, it’s not at all obvious that macroevolution must be fundamentally similar to the everyday adaptations and driftings we commonly observe real-time.

(Image from the UCMP Understanding Evolution site)

What exactly is macroevolution?

Before I continue my musings, I must first clarify what I mean by micro- and macroevolution. I see two interpretations in use in the scientific community, and I don’t think they are entirely equivalent. The “rigorous” interpretation defines microevolution as anything that happens this side of speciation. Populations adapting to short-term environmental change, individuals and their genes migrating back and forth between neighbouring populations, ordinary everyday genetic drift, etc. are microevolutionary phenomena. Macroevolution starts with the formation of new species. The “wishy-washy” interpretation defines macroevolution as “evolution on the large scale”, or “big change”. This is the one I think many palaeontologists would prefer, and many students of evo-devo as well. This is also the one most creationists seem to have in mind. Most – if not all – of the examples in the well-worn speciation lists I’m guilty of pulling out myself are only macroevolution in the first sense. This is something people often seem unaware of: speciation and big change do not go hand in hand.

The definition I prefer (and I changed my mind on this fairly recently) is the second, because despite its vagueness, it gives us a word for something vitally important, all the things that are (usually) bigger than the evolutionary processes we can readily observe on human timescales. How did something resembling a sausage on legs give rise to the mind-boggling diversity of arthropods? How did our own ancestors end up with legs instead of fins? Why did dinosaurs grow into giants and rule the land while the ancestors of mammals retreated to the shadows? This is what macroevolution means to me. As far as I’m concerned, the population geneticists’ kind of macroevolution already has a perfectly good word for it, and that word is speciation.

The question: what is the question?

With that in mind, is macroevolution something different? This is actually at least two questions. One can ask whether the external forces that set out the path of evolution act in the same way on all scales. Did the environment always exert the same kinds of pressures on living things? The answer to this is probably no – from the appearance of oxygen in the atmosphere to the arrival of predators in animal communities, both non-living and living factors have changed the rules of ecosystems many times in earth history. Do the same sorts of pressures that determine the fate of single populations also affect whole lineages? Does selection operate on more than one level? Do the same traits that natural selection favours in ordinary times also help you in extraordinary times? (Another “no”, if David Jablonski can be believed.)

Alternatively, one can also ask whether small and large changes in the properties of organisms are governed by different intrinsic rules. Do, say, new body parts originate through the same kinds of mutations as new hair colours? Are major changes and small adjustments associated with different developmental stages (Arthur, 2008)? Did the nature of variation itself change over evolutionary time (Gould, 1989; Erwin, 2011)? That last one especially intrigues me, and it may yet return in future meanderings. (It’ll return in force if I ever muster the fortitude to discuss the Cambrian explosion ;))

The way to America

In the aforementioned creation vs. evolution debates, physical distance is a commonly used analogy for evolutionary distance. If you believe in centimetres, the argument goes, how can you not believe in kilometres? If you can walk to the kitchen, why can’t you walk a mile?

I think this analogy is worth examining a little further, because it turns out to be great parallel to the micro vs. macro issue. It is true that anyone who can walk can walk a mile. It may take long and it may tire you out, depending on your physique, but it is possible. However, it isn’t very hard to think of destinations that are simply impossible to reach by walking. I live in Europe. Barring ice ages and Bering land bridges, no amount of steps would take me to America. It is still possible for me to go there, but I have to take a flight or perhaps hop on a ship. Is macroevolution like a mile, or is it more like the distance between Europe and the New World? Does a velvet worm-like creature evolve into an arthropod by lots of tiny steps of its chubby legs, or does it take a ride with Macroevolution Airlines?

***

References:

Arthur W (2008) Conflicting hypotheses on the nature of mega-evolution. In: Minelli A & Fusco G (eds.) Evolving Pathways: Key Themes in Evolutionary Developmental Biology. Cambridge University Press, pp. 50-61

Erwin DH (2011) Evolutionary uniformitarianism. Developmental Biology 357:27-34

Gould SJ (1989) Wonderful Life: The Burgess Shale and the Nature of History. W. W. Norton & Co.

Did Not Do the Research

Maybe a random rant is not the best way to break a longish silence, but I just had to. Because WTF, Budapest Zoo?

Preamble: the aforementioned is an amazing place. I’d never recommend anyone not to visit if they got the chance. But sometimes, institutions of public education fail rather spectacularly at actually educating the public. And nothing gets me quite like “education” spreading misinformation. I didn’t rant about the painful-to-read evolution stuff I saw at London Zoo a while back, mainly because I couldn’t be bothered to thoroughly fact-check all of my million and one objections. But this, this is so annoyingly simple. And so infuriatingly wrong.

I’m referring to this:

It’s supposed to be an Oviraptor with its adorable chicks. Now, me and anatomy in general are very distant acquaintances, but surely even the last stubborn holdouts of Jurassic Park fandom have heard of feathered dinosaurs by now. Surely someone designing an exhibit/sculpting a dinosaur for a big-ass zoo would know, or find out in the course of their in-depth research that in all likelihood, everything closer to birds than, say, Allosaurus was at least a little bit fuzzy, and an Oviraptor-grade animal definitely bore feathers. Come the fuck on, surely they’ve at least heard of Caudipteryx?

The sculpture is also bunny-handed. I’ve spent enough internet time around hardcore dinosaur nerds to know that these creatures couldn’t hold their forelimbs like that without seriously damaging something. Unlike us, they couldn’t pronate their forearms. Maybe this arcane piece of information isn’t easily available outside dinosaur nerddom? But one would think that someone preparing an educational exhibit would, you know, do some research about the animals in question.

The whole fuck-up is all the more puzzling because right next to this monstrosity you find these:

Which also aren’t the best works of dinosaur art I’ve seen by a long shot, but at least they don’t look like they time-travelled from the eighties. If the “raptors” got the updated treatment, why was poor Oviraptor left behind?

The right amount of pedantry

This is a questions I’ve been wondering about ever since I first attempted to communicate with people who didn’t know all the stuff I did.

Just how pedantic should I be? Just how much scientific accuracy is it OK to sacrifice for the sake of readability?

I am a pedant by nature. Chalk it up to Asperger’s if you like, but when I write about anything remotely technical, I take the utmost care not to give misleading impressions or misuse terminology. For instance, I’ll guarantee you you will never see me use “genetic code” to mean anything other than this (source: Wikipedia):

The genetic code is the set of rules by which information encoded in genetic material (DNA or mRNA sequences) is translated into proteins (amino acid sequences) by living cells.

The code defines how sequences of three nucleotides, called codons, specify which amino acid will be added next during protein synthesis.

The genetic code is not “information in DNA”, “DNA sequence”, or whatever other vague concept journalists like to apply it to. I get disproportionately pissed if I see it misused. Likewise, I’ll tie myself in knots rather than blur the distinction between a gene and its gene product. A Hox gene doesn’t regulate other genes, the resulting Hox protein does; and a homeobox encodes, not is, a homeodomain. If I dug through my forum and blog posts, I could list many more examples of my absolutely anal attitude towards terminology.

Am I overdoing it? It’s a good bet most people who might stumble on this blog are not molecular biologists, and I’m as sure as sure can be that my creationist “audience” over at Christian Forums wouldn’t know what a gene was if it came with an info board like animals in the zoo. By making these technical distinctions, am I just causing more confusion? Am I turning off potential readers? Is it better for me as a science communicator to go the journalist route and not give a shit whether I was talking about a gene, or the protein – or RNA* – it contains the instructions for?

(And – would I hate myself for it?)

***

*See, I just had to add that. Because not all genes encode proteins, and somehow that matters in a post that has nothing to do with genes. If you didn’t know what I was talking about, this footnote is pretty much it.

Pictures, thousand words, and a shout-out to UC Berkeley

One of my pet peeves – probably my biggest pet peeve – about depictions of evolution is how everything is always focused on its “pinnacles” (read: us).

I have a lovely t-shirt from BioMed Central, publisher of awesome open-access science journals. It has a nicely designed tree of life on the front, wrapped up in a stylised cell membrane. I think that’s a really neat idea, and graphically, it’s executed in a very attractive way.

I really don’t like the contents of the tree.

Look at the organisms with the little silhouettes. There are 30 figures, 12 of which are vertebrates, 5 of which are mammals. Arthropods, the most species-rich animal phylum by a margin bigger than the rest of the animal kingdom, are dwarfed in comparison. A single clutch of assorted prokaryotes stands in for two of the three great domains of life, and single-celled eukaryotes are absent except for some yeasts. The tree isn’t even fair to vertebrates. Mammals (5 figures) number between 5-6000 known species, birds (1 figure) around 10 000, ray-finned fishes (1 figure) well over 20 000.

Maybe I wouldn’t mind this sort of thing so much if it didn’t reinforce most people’s unconscious (and completely wrong) picture of evolution. But as the wise man said, pictures are worth a thousand words, and this picture screams that everything aside from mammals is the “miscellany” of biodiversity. (I guess they did treat plants pretty fairly. I’ll give them that.)

This is why I was madly happy to find this:

The picture is from UC Berkeley’s Understanding Evolution site, which I already loved to pieces, but spotting this gem made me love it even more. This is how a tree of life should be illustrated. Clear, pretty, colourful, decorated with nice pictures – and completely non-mammal-centric. Since you are an animal and presumably interested in your own kind, you can click to zoom in on animals, then on vertebrates (which doesn’t actually work for me), but first you are confronted with the tininess of our corner of the tree. I especially love how they didn’t pick a vertebrate (let alone a mammal) to represent animals among the photos.

I’m probably being unfair here, comparing a t-shirt design made purely for aesthetic reasons and a diagram fully intended to educate. Still, a tree of life divided this way can be just as pleasing to the eye as a tree of life pretending that mammals are the point of evolution – and it’s not even the case that BMC Biology, which the t-shirt advertises, is a mammal-specific journal. I think it wouldn’t hurt for t-shirt designers to re-examine their default settings every now and then 🙂

And now, a Coronacollina rant.

Coronacollina aside: great discovery + science communication fail = grumpy Mammal.

Now that we’ve drunk a few metaphorical beverages of choice to the melodiously named little sponge, allow me a rantish tangent on the terribly written press release that accompanies the paper. It makes me roll my eyes right off the bat by saying that “life” exploded in the Cambrian. No, no, no. Animals did. Plenty of other life forms didn’t, far as I know.

This, especially the part I bolded, just seems to come out of nowhere: “The finding provides insight into the evolution of life — particularly, early life — on the planet, why animals go extinct, and how organisms respond to environmental changes. The discovery also can help scientists recognize life elsewhere in the universe.” Excuse me, but where the fuck did that come from? Needless to say there’s not a word about extraterrestrial life in the entire paper, and not much about extinction or environmental change, either.

Then the article goes on to, well, not so much “suggest” as outright claim that no Precambrian animals with hard skeletons were known before this discovery: “’Up until the Cambrian, it was understood that animals were soft bodied and had no hard parts,’ said Mary Droser, a professor of geology at the University of California, Riverside, whose research team made the discovery in South Australia. ‘But we now have an organism with individual skeletal body parts that appears before the Cambrian.’” Cloudina and Namacalathus beg to differ, and I would bet money that Mary Droser knows this. In fact, Cloudina is referenced in the paper as an example of Precambrian hard parts. I’m undecided on what’s worse, if Droser fibbed about the fossil record, or if whoever edited her comments was clueless. And this is a fairly important piece of information, as the truth makes the significance of poor Coronacollina slightly less obvious. (Hmm…)

The next “highlight” (lowlight???) is where it says Coronacollina was constructed like Cambrian sponges. No, it was constructed like a Cambrian sponge, and an unusual one at that. There were many other Cambrian sponges that looked nothing like these prickly cones, see an assortment from the Burgess Shale here.

Then comes this characterisation: “[C. acula was s]haped like a thimble to which at least four 20-40-centimeter-long needle-like “spicules” were attached…” Um, someone didn’t read the paper here. It’s at most four in the known specimens, although the authors do speculate that there could’ve been more in life. And the lower end of their lengths has one fewer zero…

The crowning misreading near the end: “Droser explained that the spicules had to have been mineralized because the casts show they are ruler-straight. Moreover, they broke.” Dear article writer, I don’t know what she “explained” in person, but the paper describes the spicules (bolding mine) as “straight, rigid structures that were most commonly broken once disarticulated. Some spicules display a slight deviation from ruler-straight, implying either a composition of chitin that was plastic during life, or a mineralized composition of biogenic silica or calcium carbonate preserved deformed due to plastic behavior postburial” Newsflash: chitin is not a mineral. Granted, later in the paper they reason that some sort of mineral is most likely due to the apparent brittleness of the spicules, but they clearly don’t rule out a mainly organic composition.

Grah. I hate how press releases often get so many things wrong, and this one isn’t even a decent piece of writing. Disappointing doesn’t even begin to describe it.